ObjectiveTo optimize the extraction method for polysaccharides from turnip（Brassica rapa）， and analyze and evaluate the primary structure of the isolated and purified turnip polysaccharide fraction（BP-1） and its hypoglycemic effects in diabetic zebrafish. MethodsTaking polysaccharide yield as the evaluation index， a semi-bionic extraction method was employed. Single-factor experiments and Box-Behnken response surface methodology were used to investigate three factors of solid-to-liquid ratio， extraction time and extraction temperature， in order to optimize the extraction process. BP-1 was isolated and purified using the Sevage method and DEAE-52 cellulose column chromatography. Structural characterization of the turnip polysaccharides was performed using ultraviolet-visible spectrophotometry（UV）， gas chromatography-mass spectrometry（GC-MS）， Congo red assay， and Fourier-transform infrared spectroscopy（FT-IR） to determine purity， monosaccharide composition， triple-helix structure， and functional groups. The microstructure of the polysaccharides was observed using scanning electron microscopy（SEM） and atomic force microscopy（AFM）. Zebrafish were divided into the blank group（adding E3 medium）， and BP-1-1， BP-1-10， BP-1-50， BP-1-200， BP-1-1 000 groups（adding BP-1 solutions at concentrations of 1， 10， 50， 200， 1 000 mg·L^-1， respectively）， and zebrafish embryos were subjected to a 96-hour exposure experiment. The maximum tolerated concentration of BP-1 in zebrafish was determined by evaluating its effects on phenotype， survival rate， malformation rate， and heart rate. Experimental animals were randomly divided into the blank group， model group， BP-1-10 group（10 mg·L^-1）， BP-1-50 group（50 mg·L^-1）， and BP-1-200 group（200 mg·L^-1）. The blank group was cultured in E3 medium， the model and treatment groups were induced to establish a diabetic model in 4 day-post-fertilization（dpf） zebrafish embryos using 10 g·L^-1 of glucose combined with 500 µmol·L^-1 of alloxan. The treatment groups received corresponding doses of BP-1 solution， while the blank and model groups received an equal volume of saline. Glucose and insulin（INS） levels were measured using enzyme-linked immunosorbent assay（ELISA） kits， the effects on the liver were observed by hematoxylin-eosin（HE） histopathological sections. The mRNA expression levels of glucagon（Glucagon）， insulin（Insa）， and phosphoenolpyruvate carboxykinase 1（PCK1） were detected with real-time fluorescence quantitative polymerase chain reaction（Real-time PCR）. ResultsThe optimized extraction conditions were determined as follows：solid-to-liquid ratio of 1∶40（g·mL^-1）， extraction time of 66 min， and extraction temperature of 79 ℃. Under these conditions， the yield of turnip polysaccharides was （10.34±0.96）%. UV analysis indicated that BP-1 contained no proteins or nucleic acids， GC-MS analysis revealed that BP-1 consisted of six monosaccharides（arabinose， rhamnose， ribose， mannose， galactose and glucose）. Congo red assay indicated that the molecular conformation did not exhibit a triple-helix structure， FT-IR analysis showed the presence of α-glycosidic bonds and uronic acids， SEM analysis revealed an irregular flaky structure with a flat and smooth surface， AFM analysis suggested that the aggregated structure might be formed by the entanglement of molecular chains and intramolecular hydrogen bonding. The maximum tolerated concentration of BP-1 in zebrafish over 96 h was determined to be 200 mg·L^-1. Pharmacodynamic results showed that， compared with the blank group， the model group exhibited significantly increased glucose levels and significantly decreased INS levels（P<0.01）. Compared with the model group， the BP-1-50 group significantly reduced glucose levels and increased INS levels（P<0.05）. Histopathological examination of liver tissue revealed that various doses of BP-1 had a certain reparative effect on damaged liver tissue. The liver tissue structure in the BP-1-200 group was nearly normal， with hepatocytes appearing plump. Real-time PCR results showed that， compared with the blank group， the model group exhibited significantly upregulated mRNA expressions of Glucagon and PCK1， and significantly downregulated mRNA expression of Insa（P<0.01）. Compared with the model group， the BP-1-50 and BP-1-200 groups showed significantly downregulated mRNA expressions of Glucagon and PCK1， and significantly upregulated mRNA expression of Insa（P<0.01）. ConclusionThe semi-bionic extraction method for turnip polysaccharides yields a high extraction rate， is simple to operate， has low costs， making it suitable for large-scale industrial production. BP-1 consists of six monosaccharides， contains α-glycosidic bonds and uronic acids， exhibits hypoglycemic activity， and provides a certain protective effect on the liver of alloxan-induced diabetic model zebrafish.

ObjectiveTo optimize the extraction method for polysaccharides from turnip（Brassica rapa）， and analyze and evaluate the primary structure of the isolated and purified turnip polysaccharide fraction（BP-1） and its hypoglycemic effects in diabetic zebrafish. MethodsTaking polysaccharide yield as the evaluation index， a semi-bionic extraction method was employed. Single-factor experiments and Box-Behnken response surface methodology were used to investigate three factors of solid-to-liquid ratio， extraction time and extraction temperature， in order to optimize the extraction process. BP-1 was isolated and purified using the Sevage method and DEAE-52 cellulose column chromatography. Structural characterization of the turnip polysaccharides was performed using ultraviolet-visible spectrophotometry（UV）， gas chromatography-mass spectrometry（GC-MS）， Congo red assay， and Fourier-transform infrared spectroscopy（FT-IR） to determine purity， monosaccharide composition， triple-helix structure， and functional groups. The microstructure of the polysaccharides was observed using scanning electron microscopy（SEM） and atomic force microscopy（AFM）. Zebrafish were divided into the blank group（adding E3 medium）， and BP-1-1， BP-1-10， BP-1-50， BP-1-200， BP-1-1 000 groups（adding BP-1 solutions at concentrations of 1， 10， 50， 200， 1 000 mg·L^-1， respectively）， and zebrafish embryos were subjected to a 96-hour exposure experiment. The maximum tolerated concentration of BP-1 in zebrafish was determined by evaluating its effects on phenotype， survival rate， malformation rate， and heart rate. Experimental animals were randomly divided into the blank group， model group， BP-1-10 group（10 mg·L^-1）， BP-1-50 group（50 mg·L^-1）， and BP-1-200 group（200 mg·L^-1）. The blank group was cultured in E3 medium， the model and treatment groups were induced to establish a diabetic model in 4 day-post-fertilization（dpf） zebrafish embryos using 10 g·L^-1 of glucose combined with 500 µmol·L^-1 of alloxan. The treatment groups received corresponding doses of BP-1 solution， while the blank and model groups received an equal volume of saline. Glucose and insulin（INS） levels were measured using enzyme-linked immunosorbent assay（ELISA） kits， the effects on the liver were observed by hematoxylin-eosin（HE） histopathological sections. The mRNA expression levels of glucagon（Glucagon）， insulin（Insa）， and phosphoenolpyruvate carboxykinase 1（PCK1） were detected with real-time fluorescence quantitative polymerase chain reaction（Real-time PCR）. ResultsThe optimized extraction conditions were determined as follows：solid-to-liquid ratio of 1∶40（g·mL^-1）， extraction time of 66 min， and extraction temperature of 79 ℃. Under these conditions， the yield of turnip polysaccharides was （10.34±0.96）%. UV analysis indicated that BP-1 contained no proteins or nucleic acids， GC-MS analysis revealed that BP-1 consisted of six monosaccharides（arabinose， rhamnose， ribose， mannose， galactose and glucose）. Congo red assay indicated that the molecular conformation did not exhibit a triple-helix structure， FT-IR analysis showed the presence of α-glycosidic bonds and uronic acids， SEM analysis revealed an irregular flaky structure with a flat and smooth surface， AFM analysis suggested that the aggregated structure might be formed by the entanglement of molecular chains and intramolecular hydrogen bonding. The maximum tolerated concentration of BP-1 in zebrafish over 96 h was determined to be 200 mg·L^-1. Pharmacodynamic results showed that， compared with the blank group， the model group exhibited significantly increased glucose levels and significantly decreased INS levels（P<0.01）. Compared with the model group， the BP-1-50 group significantly reduced glucose levels and increased INS levels（P<0.05）. Histopathological examination of liver tissue revealed that various doses of BP-1 had a certain reparative effect on damaged liver tissue. The liver tissue structure in the BP-1-200 group was nearly normal， with hepatocytes appearing plump. Real-time PCR results showed that， compared with the blank group， the model group exhibited significantly upregulated mRNA expressions of Glucagon and PCK1， and significantly downregulated mRNA expression of Insa（P<0.01）. Compared with the model group， the BP-1-50 and BP-1-200 groups showed significantly downregulated mRNA expressions of Glucagon and PCK1， and significantly upregulated mRNA expression of Insa（P<0.01）. ConclusionThe semi-bionic extraction method for turnip polysaccharides yields a high extraction rate， is simple to operate， has low costs， making it suitable for large-scale industrial production. BP-1 consists of six monosaccharides， contains α-glycosidic bonds and uronic acids， exhibits hypoglycemic activity， and provides a certain protective effect on the liver of alloxan-induced diabetic model zebrafish.

OBJECTIVE To investigate the effects of Brassica rapa polysaccharide （BRP） on the Toll-like receptor 4 （TLR4）/ myeloid differentiation factor 88 （MyD88）/nuclear factor-κB （NF-κB）， AMP-activated protein kinase （AMPK）/sterol regulatory element-binding protein-1c （SREBP-1c） pathways， intestinal microbiota and liver metabolism of mice with alcoholic liver injury， and preliminarily elucidate its mechanism for improving alcoholic liver injury. METHODS Seventy-two mice were randomly divided into blank group （normal saline）， model group （normal saline）， bifendate group （positive control， 300 mg/kg） and BRP low-， medium- and high-dose groups （75， 150 and 300 mg/kg）. They were given relevant medicine intragastrically， once a day， for consecutive 9 d. After the last administration， mice in all groups except the blank group were gavaged with white liquor to establish an alcoholic liver injury model. The levels of alanine aminotransferase and aspartate aminotransferase in serum， total cholesterol， triglycerides， low-density lipoprotein cholesterol， interleukin-6， interleukin-1β， tumor necrosis factor- α and lipopolysaccharide， as well as protein expressions of TLR4， MyD88， NF-κB p65， phosphorylated NF-κB p65 （p-NF-κB p65）， AMPK， phosphorylated AMPK （p-AMPK）， and SREBP-1c were all detected； pathological morphological changes of liver tissue and colon were observed. 16S rRNA was used to detect the changes of intestinal microbiota in mice， and metabolomics 2022B02058） technology was used to detect the changes of liver metabolites. RESULTS Compared with model group， the above biochemical indicators and the protein expressions of TLR4， MyD88， p-NF-κB p65， and SREBP-1c in liver tissues were all significantly decreased （P＜0.05 or P＜0.01）， while the protein expression of p-AMPK was significantly increased （P＜0.05 or P＜0.01）. Pathological damage to liver and colon tissues was significantly improved. Medium dose of BRP could increase the relative abundance of Akkermansia， norank_f_Muribaculaceae and Lachnospiraceae_NK4A136_group in the intestinal contents of mice to a certain extent， and decrease the relative abundance of Lactobacillus and Escherichia-Shigella. A total of 9 differential metabolites were identified by metabolomics， including homogentisic acid， myristyl lysophosphatidylcholine， which were involved in pathways such as tyrosine metabolism. CONCLUSIONS BRP can regulate the relative abundance of beneficial flora， reduce the relative abundance of harmful flora， improve the structure of intestinal colonies， reduce the entry of pro-inflammatory mediator lipopolysaccharides into liver tissue， affect metabolic pathways such as tyrosine metabolism and the expression of TLR4/MyD88/NF- κB and AMPK/SREBP-1c signaling pathways in the liver， and ultimately improve alcoholic liver injury.

Objective:To determine the epidemic characteristics of polymyxin resistance ( mcr) genes of Enterobacteriales colonized in patients admitted to hospitals in Zhejiang, Henan, Gansu and Shandong provinces in China in 2023. Methods:A comprehensive collection of 667 fecal specimens from patients admitted to five medical facilities across the provinces of Zhejiang, Henan, Gansu, and Shandong in 2023 was collected. Epidemiological characteristics of Enterobacteriales bacteria positive for the mcr gene were examined, employing techniques such as microbial culturing, using agarose gel electrophoresis, PCR, whole-genome sequencing, bioinformatics analysis, and the induction of antimicrobial resistance. Statistical analysis was subsequently applied to the gathered data. Results:Among 667 fecal samples from admitted patients, five samples were positive for mcr gene, with a carrier rate of 0.75%(5/667), and from two of the samples, two different strains carrying the mcr gene were isolated, respectively. A total of seven strains of Enterobacteriales carrying the mcr gene were detected, of which four strains carried mcr-1 gene and three strains carried mcr-9 gene. The positive isolates included three strains of Escherichia coli, one strain of Citrobacter braakii, Citrobacter freundii, one strain of Klebsiella pneumoniae, and one strain of Enterobacter hormaechei. The seven mcr positive strains were isolated from two distinct geographical locations within China, with four from Zhejiang Province and three from Henan Province. After whole-genome sequencing, it was found that the 16S rRNA sequences of the three strains of mcr-1 positive Escherichia coli had high homology. The three isolates of mcr-9 positive strains preserved a significant degree of homology within the mcr-9 and wbuC regions. Following polymyxin exposure, there was a marked difference in the growth kinetics of the ZJ-307, HN-11-1, and HN-135 strains post-induction compared to their pre-induction growth rates, and their motility capacity was reduced. Conclusions:The prevalence of Enterobacteriales harboring the mcr gene is minimal among hospitalized patients. However, it is noteworthy that these genes are prone to horizontal transfer. They can move into drug-resistant strains, which may have elevate minimum inhibitory concentration(MIC). Resistance to polymyxin can alter the bacterial growth rate and motility, potentially impacting the MIC of other antibiotics, thereby complicating clinical management. Consequently, it is imperative to focus on the proactive screening of susceptible populations to prevent the further dissemination of plasmid-mediated polymyxin resistance among clinically significant gram-negative bacterial pathogens.

Objective:To investigate differences in serum lipid profiles between patients with dermatomyositis (DM) and healthy controls.Methods:A retrospective analysis was conducted on the clinical data and serum samples collected from 51 patients with DM who visited the First Affiliated Hospital, Anhui Medical University from September 2020 to January 2022. Serum samples were also collected from 66 healthy controls during the same period. Serum lipid profiles were analyzed using ultra-performance liquid chromatography-mass spectrometry in both groups. Differential lipids were screened using principal component analysis and orthogonal partial least squares-discriminant analysis. The predictive value of these differential lipids for DM was evaluated by receiver operating characteristic (ROC) curve analysis, and their correlations with clinical indicators were also evaluated.Results:A total of 51 patients with DM were enrolled, including 27 males and 24 females, with ages ( M[ Q1, Q3]) of 55.00 (47.00, 66.00) years and body mass index (BMI) values of 22.64 (19.79, 24.75) . The control group included 66 healthy individuals (33 males and 33 females) , with ages of 51.00 (43.75, 56.00) years and BMI values of 23.60 (21.18, 25.19) . No significant differences were observed between the two groups in terms of sex, age, or BMI (all P > 0.05) . A total of 341 lipid metabolites were identified, and 16 lipid metabolites such as ceramides (Cer) , sphingomyelins, phosphatidylcholines (PC) , phosphatidylethanolamines, lysophosphatidylcholines (LPC) , and triglycerides (TG) significantly differed between the DM group and the control group, of which 8 were upregulated and 8 were downregulated in the DM group. ROC curve analysis identified 7 differential lipids with area under the curve (AUC) values of > 0.9, of which 2 were Cer, 3 were TG, 1 was phosphatidylethanolamine, and 1 was LPC. In the DM patients, serum LPC (22∶1) levels were negatively correlated with creatine kinase isoenzyme MB levels ( r = -0.276, P < 0.05) , serum PC (15∶1/16∶0) levels were negatively correlated with aspartate aminotransferase levels ( r = -0.305, P < 0.05) , and serum Cer (d18∶1/18∶0) levels were positively correlated with C-reactive protein levels ( r = 0.283, P < 0.05) . Significant differences in serum lipid levels were observed between some DM subgroups (all P < 0.05) : sphingomyelin (d24∶0) levels significantly differed between anti-Sj?gren syndrome type A/Ro52 antibody-positive and -negative DM patients; LPC (17∶1) levels significantly differed between anti-PM-SCL75 antibody-positive and -negative DM patients; LPC (20∶0) and PC (32∶1p) levels significantly differed between anti-Mi-2 antibody-positive and -negative DM patients; LPC (22∶1) and TG (9∶0/9∶0/9∶0) levels significantly differed between anti-TIF1-γ antibody-positive and -negative DM patients; Cer (d18∶1/18∶0) levels significantly differed between DM patients with and without Heliotrope's sign. Conclusion:Lipid profiles were significantly altered in DM patients compared with healthy controls, and some lipids showed potential diagnostic value for DM.

The specific mechanisms of interferon regulatory factor 8(IRF8)in porcine intestinal in-nate immunity and resistance to enteric virus infection remain to be elucidated.To investigate the immunoregulatory role of IRF8,establishing an IRF8 gene knockout porcine intestinal epithelial cell(IPEC-J2)monoclonal cell line is of significant importance.This study initially aimed to obtain recombinant adeno-associated virus rAAV-sgIRF8-eGFP capable of knocking out the IRF8 gene through co-transfection of HEK-293T cells with three plasmids.Subsequently,IPEC-J2 cells were infected with the virus,and those expressing eGFP were selected by flow cytometry and cultured to form monoclonal cell lines.These cell lines were then identified by Sanger sequencing and West-ern blot techniques.Lastly,qPCR analysis was used to measure the expression levels of interferon factors IFN-α,IFN-β,IFN-γ and IFN-λ,providing preliminary insights into the impact of IRF8 gene knockout on IPEC-J2 cell immunity.The results demonstrated successful generation of rAAV-sgIRF8-eGFP,which successfully infected IPEC-J2 cells leading to eGFP fluorescence.Flow cytometry followed by cell culture led to the establishment of two monoclonal cell lines,IRF8-KO1 and IRF8-KO3.Sanger sequencing revealed a five-base deletion in IRF8-KO1 and a seven-base dele-tion in IRF8-KO3.Western blot confirmed the absence of IRF8 protein expression in IRF8-KO1,making it an ideal candidate monoclonal cell line.qPCR analysis of interferon factors indicated sig-nificant decrease in IFN-γ(P＜0.05)and IFN-λ(P＜0.01)transcription level in IRF8-knockout cells,while the transcription levels of IFN-α and IFN-β remained relatively unchanged.This study successfully established an IRF8 gene knockout IPEC-J2 monoclonal cell line,providing a founda-tion for further research on IRF8-related porcine intestinal immune regulation and mechanisms of intestinal virus infection.

BACKGROUND:In recent years,improving the health of skeletal muscles through exercise has become an important research concern for scholars.Appropriate exercise has a positive effect on skeletal muscles.Among them,how to activate the sphingosine kinase1(SphK1)/sphingosine-1-phase(S1P)/sphingosine-1-phase receptor2(S1PR2)signaling pathway during exercise so as to improve the health of skeletal muscles is receiving attention from researchers. OBJECTIVE:To investigate how exercise improves the health of skeletal muscles through the SphK1/S1P/S1PR2 signaling pathway,and to explore new methods for treating related muscle diseases in order to improve human skeletal muscle health. METHODS:The first author searched for relevant literature from the establishment of the database to the present in the Web of Science,PubMed,CNKI,WanFang,and VIP databases.The search terms were"signaling pathway,SphK1,S1P,S1PR2,skeletal muscle,satellite cell,myogenesis,exercise"in Chinese and English.Finally,69 articles were included for review and analysis. RESULTS AND CONCLUSION:The SphK1/S1P/S1PR2 signaling pathway is a complex regulatory network that triggers downstream signal transduction processes by SphK1 to catalyze the interaction between S1P and receptors such as S1PR2,thereby regulating multiple biological functions of cells,tissues,organs,and systems.The SphK1/S1P/S1PR2 signaling pathway can regulate satellite cell proliferation and myoblast differentiation,improving myogenesis.The physiological basis of the SphK1/S1P/S1PR2 signaling pathway and the potential impact of exercise on it were analyzed through literature research.Acute aerobic exercise can increase the expression of SphK1 in skeletal muscle.Both human and animal studies have confirmed that acute and long-term exercise can increase the expression of S1P in skeletal muscle.In addition,studies have shown that long-term resistance exercise can increase the expression of S1PR2 in skeletal muscle.Some experimental results indicate that acute and long-term exercise have no significant effect on muscle or blood S1P levels,and the reason for different results may be due to different research subjects,methods,intensities,and frequencies selected,while the specific mechanism is not yet clear.Research suggests that exercise can promote the expression of the SphK1/S1P/S1PR2 signaling pathway in skeletal muscle and regulate downstream related signaling pathways.Research on this signaling pathway may provide new strategies and methods for the treatment of skeletal muscle diseases,thereby improving skeletal muscle health.In the future,we should deepen the research on the association between SphK1/S1P/S1PR2 signaling pathway and skeletal muscle health,further reveal its regulatory relationship with satellite cells and myoblasts as well as its interactions with the upstream and downstream pathways,explore its clinical application value,take into account the changes of this pathway when formulating the rehabilitation program,explore the specific mechanisms by which different types of exercise affect the SphK1/S1P/S1PR2 signaling pathway in skeletal muscles,and use the SphK1/S1P/S1PR2 signaling pathway as a potential therapeutic target for diseases.Further development and application of human muscle models should be developed to improve research depth and accuracy.

Objective To evaluate the quality of cisatracurium besilate injection produced by domestic manufacturers.Methods A comprehensive evaluation of 104 batches of samples was carried out using statutory testing methods combined withexploratory research,including related substances,1,5-pentanediol diacrylate,residual solvents,genotoxic impurities of benzenesulfonate esters,infrared spectrum,and endotoxin examination.The quality of domestic products and the controllability of current specifications were comprehensively evaluated.Results According to the statutory tests,the qualified rate of 104 batches of samples was 100.0％.The exploratory research showed that the results of related substances in the samples produced by 6 manufacturers were far below the limit,and no genotoxic impurities of benzenesulfonate esters were detected.However,the results showed that there was variability in 1,5-pentanediol diacrylate,as well as residual solvents.Conclusions The quality of the cisatracurium besilate injection is good,and the current specifications should be further improved and unified.It was proposed that the infrared spectrum,related substance,and 1,5-pentanediol diacrylate method be added or revised,and the limit of endotoxin strictly controlled.It was proposed that manufacturers pay attention to the quality of API and control injection production.

The specific mechanisms of interferon regulatory factor 8(IRF8)in porcine intestinal in-nate immunity and resistance to enteric virus infection remain to be elucidated.To investigate the immunoregulatory role of IRF8,establishing an IRF8 gene knockout porcine intestinal epithelial cell(IPEC-J2)monoclonal cell line is of significant importance.This study initially aimed to obtain recombinant adeno-associated virus rAAV-sgIRF8-eGFP capable of knocking out the IRF8 gene through co-transfection of HEK-293T cells with three plasmids.Subsequently,IPEC-J2 cells were infected with the virus,and those expressing eGFP were selected by flow cytometry and cultured to form monoclonal cell lines.These cell lines were then identified by Sanger sequencing and West-ern blot techniques.Lastly,qPCR analysis was used to measure the expression levels of interferon factors IFN-α,IFN-β,IFN-γ and IFN-λ,providing preliminary insights into the impact of IRF8 gene knockout on IPEC-J2 cell immunity.The results demonstrated successful generation of rAAV-sgIRF8-eGFP,which successfully infected IPEC-J2 cells leading to eGFP fluorescence.Flow cytometry followed by cell culture led to the establishment of two monoclonal cell lines,IRF8-KO1 and IRF8-KO3.Sanger sequencing revealed a five-base deletion in IRF8-KO1 and a seven-base dele-tion in IRF8-KO3.Western blot confirmed the absence of IRF8 protein expression in IRF8-KO1,making it an ideal candidate monoclonal cell line.qPCR analysis of interferon factors indicated sig-nificant decrease in IFN-γ(P＜0.05)and IFN-λ(P＜0.01)transcription level in IRF8-knockout cells,while the transcription levels of IFN-α and IFN-β remained relatively unchanged.This study successfully established an IRF8 gene knockout IPEC-J2 monoclonal cell line,providing a founda-tion for further research on IRF8-related porcine intestinal immune regulation and mechanisms of intestinal virus infection.