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.

BACKGROUND:Cervical disc herniation can cause pain in the neck and shoulder area,as well as radiating pain in the upper limbs.The incidence rate is increasing year by year and tends to affect younger individuals.Fully understanding the biomechanical characteristics of the cervical spine in adolescents is of great significance for preventing and delaying the onset of cervical disc herniation in this age group. OBJECTIVE:To reconstruct cervical spine models for both healthy adolescents and adolescent patients with cervical disc herniation utilizing finite element analysis techniques,to analyze the motion range of the C1-T1 cervical vertebrae as well as the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and the cartilage of the small joints. METHODS:A normal adolescent's cervical spine and an adolescent patient with cervical disc herniation were selected in this study.The continuous scan cervical spine CT raw image data were imported into Mimics 21.0 in DICOM format.The C1-T1 vertebrae were reconstructed separately.Subsequently,the established models were imported into the 3-Matic software for disc reconstruction.The perfected models were then imported into Hypermesh software for meshing of the vertebrae,nucleus pulposus,annulus fibrosus,and ligaments,creating valid geometric models.After assigning material properties,the final models were imported into ABAQUS software to observe the joint motion range of the C1-C7 cervical vertebrae segments under different conditions,and to analyze the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and small joint cartilage of each cervical spine segment. RESULTS AND CONCLUSION:(1)In six different conditions,the joint motion range of the C1 vertebra in the cervical spine models of both normal adolescent and adolescent patient with cervical disc herniation was higher than that of the other vertebrae.Additionally,the joint motion range of each cervical spine segment in normal adolescent was greater than that in adolescent patient with cervical disc herniation.(2)In the cervical spine model of normal adolescent,the maximum stress values in the annulus fibrosus and nucleus pulposus were found on the left side during C2-3 flexion conditions(0.43 MPa and 0.17 MPa,respectively).In the cervical spine model of adolescent patient with cervical disc herniation,the maximum stress values were found on the left side during C7-T1 flexion conditions(0.54 MPa and 0.18 MPa,respectively).(3)In the cervical spine model of normal adolescent,the maximum stress value on the endplate was found on the left side of the upper endplate of C3 during flexion conditions(1.46 MPa).In the model of adolescent patient with cervical disc herniation,the maximum stress value on the endplate was found on the left side of the lower endplate of C7 during flexion conditions(1.32 MPa).(4)In the cervical spine model of normal adolescent,the maximum stress value in the small joint cartilage was found in the C2-3 left rotation conditions(0.98 MPa).In adolescent patient with cervical disc herniation,the stress in the small joint cartilage significantly increased under different conditions,especially in C1-2,with the maximum stress found during left flexion(3.50 MPa).(5)It is concluded that compared to normal adolescent,adolescent patient with cervical disc herniation exhibits altered cervical curvature and a decrease in overall joint motion range in the cervical spine.In adolescent with cervical disc herniation,there is a significant increase in stress on the annulus fibrosus,nucleus pulposus,and endplates in the C7-T1 segment.The stress on the left articular cartilage of the C1-2 is notable.Abnormal cervical curvature may be the primary factor causing these stress changes.

BACKGROUND:A large number of articles have reported the effect and mechanism of platelet-rich plasma and hydrogel in the treatment of spinal cord injury,but few articles have summarized their treatment strategies for spinal cord injury. OBJECTIVE:To summarize the pathological process of spinal cord injury and the strategies of repairing spinal cord injury with platelet-rich plasma and hydrogel alone and in combination. METHODS:PubMed and CNKI databases were searched for articles published from inception to March 2024 by computer.The Chinese search terms were"spinal cord injury,platelet-rich plasma,hydrogel."The English search terms were"spinal cord injury,spinal cord,platelet-rich plasma,hydrogel,angiogenesis,neuralgia,combination therapy."Articles were screened according to inclusion and exclusion criteria,and 128 articles were finally included for review and analysis. RESULTS AND CONCLUSION:(1)The classification of platelet-rich plasma is complex and diverse,and the effects of platelet-rich plasma in the repair treatment of spinal cord injury are various,but they all show certain positive effects,that is,they can promote axon regeneration,stimulate angiogenesis,and treat neuropathic pain and so on.(2)The effect of platelet-rich plasma is mainly due to the growth factors contained in platelet-rich plasma.(3)There are many types of hydrogels,which mainly play the role of filling,simulating extracellular matrix,carrying drugs and biological products,and carrying cells as scaffolds in the repair treatment of spinal cord injury.(4)Compared with single therapy,combination therapy of platelet-rich plasma and hydrogel can promote nerve regeneration and spinal cord function recovery more effectively.

OBJECTIVE To sort out the evaluation mechanism and methodology of published cases of comprehensive clinical evaluation of drugs in China， and provide a reference for promoting standardized comprehensive clinical evaluation of drugs and strengthening policy transformation in China. METHODS Clinical comprehensive evaluation cases of drugs published in China from CNKI， Wanfang Data， PubMed and Web of Science were systematically searched， and the retrieval time was from the inception to December 31st， 2023. The summary and analysis were performed from the aspects of theme selection， indicator system construction， evaluation methods， comprehensive decision-making， quality control， etc. RESULTS A total of 143 pieces of literature were ultimately included from 2014 to 2023. The number of publications has shown a rapid upward trend since 2019. The subjects of the evaluation cases were mainly pediatric drugs， Chinese patent medicines， cardiovascular drugs and anti-tumor drugs. The evaluation dimensions were between 3-8， all involving safety and effectiveness dimensions. Most cases adopted rapid evaluation methods based on literature review and expert interviews/questionnaire surveys with less emphasis on real-world research. Most cases did not involve comprehensive decision-making， quality control， or policy transformation. CONCLUSIONS The clinical comprehensive evaluation of drugs in China has made rapid progress under the guidance of national policies. However， there are still issues and challenges such as incomplete evaluation methods and standards， few cases of evaluation results being converted into decision-making， and a lack of quality control mechanisms. It is suggested that standardized evaluation paths and quality control mechanisms should be explored； when the evidence-based basis is insufficient， real-world research should be conducted as much as possible， so as to accelerate the policy transformation of evaluation results.

OBJECTIVE To observe the effects of Modified shaoyao gancao decoction on intestinal transit function， intestinal flora and the contents of metabolites [γ aminobutyric acid （GABA） and 5-hydroxytryptamine （5-HT）] in slow transit constipation （STC） rats. METHODS SD rats were randomly divided into blank group （10 rats） and modeling group （30 rats）， with half male and half female. The STC model was established by intragastric administration of Compound diphenoxylate tablets in the modeling group. The successfully modeled rats were randomly divided into model group， Modified shaoyao gancao decoction group [56 g/（kg·d）， calculated by crude drug] and positive control group [lactulose 2.09 g/（kg·d）]， with 10 rats in each group. Each administration group was given relevant medicine intragastrically， the blank group and model group received an equivalent volume of normal saline， once a day， for 14 consecutive days. During the experiment， the general situation of rats was observed in each group. After the last medication， the body weight was measured， and the Bristol score was used to evaluate the fecal characteristics. The fecal moisture content， intestinal propulsion rate， and the contents of GABA and 5-HT in intestinal content were detected； the diversity of intestinal flora in intestinal contents was investigated， and the correlation between the contents of GABA， 5-HT and relative abundance of microbiota was analyzed. RESULTS Compared with the model group， general conditions such as small body shape， sparse and rough fur， and slow movement were all improved in Modified shaoyao gancao decoction body weight， Bristol score， fecal moisture content，intestinal propulsion rate， 5-HT content， Chao1 index and Shannon index were increased significantly， while GABA content and Simpson index were decreased significantly （P＜0.05）. The intestinal flora of rats in the Modified shaoyao gancao decoction group could be classified as the same as the blank group， but was far from the model group； the relative abundances of Desulfobacterota， Firmicutes and Bacteroidota in this group showed a tendency of pull back， but the differences were not statistically significant compared to model group （P＞0.05）. Desulfobacterota was an intergroup differential factor （P＜0.05）. The content of GABA was negatively correlated with the relative abundance of Bacteroidota， Cyanobacteria， Patescibacteria and Actinobacteriota （P＜0.05）. The content of 5-HT was positively correlated with the relative abundance of Campilobacterota （P＜0.05）. CONCLUSIONS Modified shaoyao gancao decoction can improve the fecal properties and intestinal motility of STC rats. Its mechanism may be related to improving intestinal flora and then affecting the contents of GABA and 5-HT in intestinal contents. In addition， the contents of GABA and 5-HT may be significantly correlated with the relative abundance of specific bacterial phyla such as Bacteroidota and Campilobacterota.

OBJECTIVE To sort out the evaluation mechanism and methodology of published cases of comprehensive clinical evaluation of drugs in China， and provide a reference for promoting standardized comprehensive clinical evaluation of drugs and strengthening policy transformation in China. METHODS Clinical comprehensive evaluation cases of drugs published in China from CNKI， Wanfang Data， PubMed and Web of Science were systematically searched， and the retrieval time was from the inception to December 31st， 2023. The summary and analysis were performed from the aspects of theme selection， indicator system construction， evaluation methods， comprehensive decision-making， quality control， etc. RESULTS A total of 143 pieces of literature were ultimately included from 2014 to 2023. The number of publications has shown a rapid upward trend since 2019. The subjects of the evaluation cases were mainly pediatric drugs， Chinese patent medicines， cardiovascular drugs and anti-tumor drugs. The evaluation dimensions were between 3-8， all involving safety and effectiveness dimensions. Most cases adopted rapid evaluation methods based on literature review and expert interviews/questionnaire surveys with less emphasis on real-world research. Most cases did not involve comprehensive decision-making， quality control， or policy transformation. CONCLUSIONS The clinical comprehensive evaluation of drugs in China has made rapid progress under the guidance of national policies. However， there are still issues and challenges such as incomplete evaluation methods and standards， few cases of evaluation results being converted into decision-making， and a lack of quality control mechanisms. It is suggested that standardized evaluation paths and quality control mechanisms should be explored； when the evidence-based basis is insufficient， real-world research should be conducted as much as possible， so as to accelerate the policy transformation of evaluation results.

OBJECTIVE To observe the effects of Modified shaoyao gancao decoction on intestinal transit function， intestinal flora and the contents of metabolites [γ aminobutyric acid （GABA） and 5-hydroxytryptamine （5-HT）] in slow transit constipation （STC） rats. METHODS SD rats were randomly divided into blank group （10 rats） and modeling group （30 rats）， with half male and half female. The STC model was established by intragastric administration of Compound diphenoxylate tablets in the modeling group. The successfully modeled rats were randomly divided into model group， Modified shaoyao gancao decoction group [56 g/（kg·d）， calculated by crude drug] and positive control group [lactulose 2.09 g/（kg·d）]， with 10 rats in each group. Each administration group was given relevant medicine intragastrically， the blank group and model group received an equivalent volume of normal saline， once a day， for 14 consecutive days. During the experiment， the general situation of rats was observed in each group. After the last medication， the body weight was measured， and the Bristol score was used to evaluate the fecal characteristics. The fecal moisture content， intestinal propulsion rate， and the contents of GABA and 5-HT in intestinal content were detected； the diversity of intestinal flora in intestinal contents was investigated， and the correlation between the contents of GABA， 5-HT and relative abundance of microbiota was analyzed. RESULTS Compared with the model group， general conditions such as small body shape， sparse and rough fur， and slow movement were all improved in Modified shaoyao gancao decoction body weight， Bristol score， fecal moisture content，intestinal propulsion rate， 5-HT content， Chao1 index and Shannon index were increased significantly， while GABA content and Simpson index were decreased significantly （P＜0.05）. The intestinal flora of rats in the Modified shaoyao gancao decoction group could be classified as the same as the blank group， but was far from the model group； the relative abundances of Desulfobacterota， Firmicutes and Bacteroidota in this group showed a tendency of pull back， but the differences were not statistically significant compared to model group （P＞0.05）. Desulfobacterota was an intergroup differential factor （P＜0.05）. The content of GABA was negatively correlated with the relative abundance of Bacteroidota， Cyanobacteria， Patescibacteria and Actinobacteriota （P＜0.05）. The content of 5-HT was positively correlated with the relative abundance of Campilobacterota （P＜0.05）. CONCLUSIONS Modified shaoyao gancao decoction can improve the fecal properties and intestinal motility of STC rats. Its mechanism may be related to improving intestinal flora and then affecting the contents of GABA and 5-HT in intestinal contents. In addition， the contents of GABA and 5-HT may be significantly correlated with the relative abundance of specific bacterial phyla such as Bacteroidota and Campilobacterota.

Objective To understand the situation of corn mycotoxins contamination in Heilongjiang Province , and to analyze the causes of pollution and propose prevention and control measures. Methods Among the 473 corn samples were collected from various regions in Heilongjiang Province , and 16 mycotoxins , including aflatoxins , fumonisins, deoxynivalenol and their metabolites , zearalenone , ochratoxin A , alternariol , alternariol monomethyl ether , tentoxin , and tenuazonic acid , were detected in the corn samples. The detection and quantification were carried out using ultra-high performance liquid chromatography tandem mass spectrometry isotope internal standard method. Results All samples were detected with mycotoxins, the detection rate was 100%, and each sample was contaminated by one or more mycotoxins. The detection rate of 16 mycotoxins ranged from 0.21% to 98.31%. The average contamination level ranged from 0.67 μ g/kg-259.19 μ g/kg. Three types of toxins exceeded the standard, with exceeding rates of deoxynivalenol (2.54%, 12/473), zearalenone (4.02% ,19/473), and fumonisins (2.54%,12/473), respectively. The samples exceeding the standard were distributed in Mudanjiang, Shuangyashan, Jixi, Harbin, and Qiqihar. Conclusion Corn in Heilongjiang Province is contaminated by a combination of mycotoxins. It is necessary to strengthen monitoring from multiple links and adopt a variety of ways and control measures to reduce corn contamination.

ObjectiveTo investigate the value of different noninvasive diagnostic models in the diagnosis of esophageal and gastric varices since there is a high risk of esophageal and gastric varices in patients with compensated hepatitis B cirrhosis and significant portal hypertension， and to provide a basis for the early diagnosis of esophageal and gastric varices. MethodsA total of 108 patients with significant portal hypertension due to compensated hepatitis B cirrhosis who attended Guangdong Provincial Hospital of Traditional Chinese Medicine from November 2017 to November 2023 were enrolled， and according to the presence or absence of esophageal and gastric varices under gastroscopy， they were divided into esophageal and gastric varices group （GOV group） and non-esophageal and gastric varices group （NGOV group）. Related data were collected， including age， sex， imaging findings， and laboratory markers. The chi-square test was used for comparison of categorical data between groups； the least significant difference t-test was used for comparison of normally distributed continuous data between groups， and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between groups. The receiver operating characteristic （ROC） curve was plotted to evaluate the diagnostic value of five scoring models， i.e.， fibrosis-4 （FIB-4）， LOK index， LPRI， aspartate aminotransferase-to-platelet ratio index （APRI）， and aspartate aminotransferase/alanine aminotransferase ratio （AAR）. The binary logistic regression method was used to establish a combined model， and the area under the ROC curve （AUC） was compared between the combined model and each scoring model used alone. The Delong test was used to compare the AUC value between any two noninvasive diagnostic models. ResultsThere were 55 patients in the GOV group and 53 patients in the NGOV group. Compared with the NGOV group， the GOV group had a significantly higher age （52.64±1.44 years vs 47.96±1.68 years， t=0.453， P<0.05） and significantly lower levels of alanine aminotransferase ［42.00 （24.00 — 17.00） U/L vs 82.00 （46.00 — 271.00） U/L， Z=-3.065， P<0.05］， aspartate aminotransferase ［44.00 （32.00 — 96.00） U/L vs 62.00 （42.50 — 154.50） U/L，Z=-2.351， P<0.05］， and platelet count ［100.00 （69.00 — 120.00）×10⁹/L vs 119.00 （108.50 — 140.50）×10⁹/L， Z=-3.667， P<0.05］. The ROC curve analysis showed that FIB-4， LOK index， LPRI， and AAR used alone had an accuracy of 0.667， 0.681， 0.730， and 0.639， respectively， in the diagnosis of esophageal and gastric varices （all P<0.05）， and the positive diagnostic rates of GOV were 69.97%， 65.28%， 67.33%， and 58.86%， respectively， with no significant differences in AUC values （all P>0.05）， while APRI used alone had no diagnostic value （P>0.05）. A combined model （LAF） was established based on the binary logistic regression analysis and had an AUC of 0.805 and a positive diagnostic rate of GOV of 75.80%， with a significantly higher AUC than FIB-4， LOK index， LPRI， and AAR used alone （Z=-2.773，-2.479，-2.206， and-2.672， all P<0.05）. ConclusionFIB-4， LOK index， LPRI， and AAR have a similar diagnostic value for esophageal and gastric varices in patients with compensated hepatitis B cirrhosis and significant portal hypertension， and APRI alone has no diagnostic value. The combined model LAF had the best diagnostic efficacy， which provides a certain reference for clinical promotion and application.

ObjectiveTo explore the potential mechanism of Xiezhuo Jiedu prescription in regulating autophagy in the treatment of ulcerative colitis （UC） by bioinformatics and animal experiments. MethodsThe differentially expressed genes （DEGs） in the colonic mucosal tissue of UC patients was obtained from the Gene Expression Omnibus （GEO）， and those overlapped with autophagy genes were obtained as the differentially expressed autophagy-related genes （DEARGs）. DEARGs were imported into Metascape and STRING， respectively， for gene ontology/Kyoto Encyclopedia of Genes and Genomics （GO/KEGG） enrichment analysis and protein-protein interaction （PPI） analysis. Finally， 15 key DEARGs were obtained. The core DEARGs were obtained by least absolute shrinkage and selection operator （LASSO） regression and receiver operating characteristic curve （ROC） analysis. The CIBERSORT deconvolution algorithm was used to analyze the immunoinfiltration of UC patients and the correlations between core DEARGs and immune cells. C57BL/6J mice were assigned into a normal group and a modeling group. The mouse model of UC was established by free drinking of 2.5% dextran sulfate sodium. The modeled mice were assigned into low-， medium-， and high-dose Xiezhuo Jiedu prescription and mesalazine groups according to the random number table method and administrated with corresponding agents by gavage for 7 days. The colonic mucosal morphology was observed by hematoxylin-eosin staining. The protein and mRNA levels of cysteinyl aspartate-specific proteinase 1 （Caspase-1）， cathepsin B （CTSB）， C-C motif chemokine-2 （CCL2）， CXC motif receptor 4 （CXCR4）， and hypoxia-inducing factor-1α （HIF-1α） in the colon tissue were determined by Western blot and real-time fluorescence quantitative polymerase chain reaction， respectively. ResultsThe dataset GSE87466 was screened from GEO and interlaced with autophagy genes. After PPI analysis， LASSO regression， and ROC analysis， the core DEARGs （Caspase-1， CCL2， CTSB， and CXCR4） were obtained. The results of immunoinfiltration analysis showed that the counts of NK cells， M0 macrophages， M1 macrophages， and dendritic cells in the colonic mucosal tissue of UC patients had significant differences， and core DEARGs had significant correlations with these immune cells. This result， combined with the prediction results of network pharmacology， suggested that the HIF-1α signaling pathway may play a key role in the regulation of UC by Xiezhuo Jiedu prescription. The animal experiments showed that Xiezhuo Jiedu prescription significantly alleviated colonic mucosal inflammation in UC mice. Compared with the normal group， the model group showed up-regulated protein and mRNA levels of caspase-1， CCL2， CTSB， CXCR4， and HIF-1α， which were down-regulated after treatment with Xiezhuo Jiedu prescription or mesalazine. ConclusionCaspase-1， CCL2， CTSB， and CXCR4 are autophagy genes that are closely related to the onset of UC. Xiezhuo Jiedu prescription can down-regulate the expression of core autophagy genes to alleviate the inflammation in the colonic mucosa of mice.