BACKGROUND:The capability of repairing articular cartilage damage is very limited,and tissue engineering technology provides new therapeutic options for repairing damaged cartilage,in which the interaction and induction between chondrocytes,bone marrow mesenchymal stem cells,and synovial mesenchymal stem cells is the basis of autologous healing of cartilage damage. OBJECTIVE:To construct the chondrocyte-bone marrow mesenchymal stem cell-synovial mesenchymal stem cell co-culture system to simulate the in vitro microenvironment of chondrocytes,and to explore the optimal cell inoculation ratio,meanwhile to observe the effects of icariin-containing serum on the proliferation of chondrocytes and the chondrogenic differentiation of stem cells in the system. METHODS:Rat knee chondrocytes,bone marrow mesenchymal stem cells and synovial mesenchymal stem cells were extracted,cultured and identified,and a chondrocyte-bone marrow mesenchymal stem cell-synovial mesenchymal stem cell non-contact co-culture system was constructed according to different cell inoculation ratios.After 72 hours of co-culturing,the chondrocyte proliferative activity and phenotypic ability were observed,and the co-culture system with the best overall effect was selected.New Zealand white rabbits were gavaged with icariin solution(0.25 mg/mL)to prepare icariin-containing serum,and cultured in conventional complete medium(high sugar DMEM culture medium containing 10%fetal bovine serum and 1%double antibody by volume)as the control group,while the experimental group was intervened by adding 10%icariin-containing serum by volume on the basis of above.The proliferative activity of chondrocytes and the expression of collagen type II were tested for the two groups after 24 and 48 hours.The differentiation of bone marrow mesenchymal stem cells and synovial mesenchymal stem cells into chondrocytes in the co-culture system was tested by immunofluorescence staining after 14 days. RESULTS AND CONCLUSION:(1)The three kinds of cells grew normally adherently to the wall in different ratios of co-culture,where chondrocytes showed the best proliferative activity and phenotypic ability in the co-culture system when chondrocytes:bone marrow mesenchymal stem cells:synovial mesenchymal stem cells=2:1:1.(2)Compared with the control group,the proliferative activity and type II collagen expression of chondrocytes in the experimental group were significantly increased after 24 hours(P<0.01),and the two groups still had difference after 48 hours(P<0.05).The two groups showed obvious chondrogenic differentiation of bone marrow mesenchymal stem cells and synovial mesenchymal stem cells after 14 days(P<0.01),and some of the cells appeared round or oval,and the cytoplasmic type II collagen immunofluorescence staining was positive.The fluorescence intensity of the experimental group was significantly higher than that of the control group(P<0.01).(3)The results showed that the chondrocyte-bone marrow mesenchymal stem cell-synovial mesenchymal stem cell co-culture system could be successfully established by the non-contact co-culture method,and the best chondrocyte proliferative activity and phenotypic ability could be obtained when the cell ratio was 2:1:1.Icariin-containing serum had the promoting effect on chondrocyte proliferation,and chondrogenic differentiation of bone marrow mesenchymal stem cells and synovial mesenchymal stem cells in the system.

Corynebacterium pseudotuberculosis(C.pseudotuberculosis)is a group of intracellular Gram-positive bacteria that can cause zoonotic diseases.This study investigated the mechanisms of inflammatory mediator secretion and the phagocytic and bactericidal functions of mouse peritoneal macrophages following C.pseudotuberculosis infection.Initially,transcriptomic sequencing was em-ployed to identify genes critical for C.pseudotuberculosis infection in macrophages.Subsequently,gene knockout mice were utilized to assess the impact of these key genes on inflammatory media-tor secretion,activation of inflammatory signaling pathways,and the phagocytic and bactericidal functions of macrophages infected with C.pseudotuberculosis.Techniques such as ELISA,Western blot,and immunofluorescence were employed in this analysis.Further,transcriptomic sequencing was conducted to identify key downstream genes.Following C.pseudotuberculosis infection,GO enrichment analysis was performed,and TLR2 was identified as the focal point of the study.Perito-neal macrophages from C57BL/6J and TLR2 knockout(TLR2-/-)mice were infected with C.pseudotuberculosis.ELISA results revealed that the levels of TNF-α,IL-1β,and IL-10 were signifi-cantly downregulated in TLR2-/-macrophages compared to C57BL/6J macrophages post-infec-tion.Western blot demonstrated that the absence of TLR2 led to a marked decrease in M APK(p38 and ERK)signaling pathway phosphorylation following C.pseudotuberculosis infection.Immuno-fluorescence results indicated that the phagocytic rate of TLR2-/-macrophages was significantly higher than that of C57BL/6J macrophages after infection.Subsequently,transcriptomic analysis of C57BL/6J and TLR2-/-macrophages infected with C.pseudotuberculosis was performed,followed by GO enrichment analysis of differential genes.IL-36a,Cx3cr1,TLR1,and TLR2 were identified as key differential genes.TLR2 plays a crucial role in the inflammatory response induced by C.pseudotuberculosis infection in mice,influencing the progression of the inflammatory response and host outcomes through the secretion of inflammatory mediators,activation of signaling pathways,and modulation of phagocytic and bactericidal functions.IL-36a and Cx3cr1 were identified as key downstream factors in this process.

Corynebacterium pseudotuberculosis(C.pseudotuberculosis)is a group of intracellular Gram-positive bacteria that can cause zoonotic diseases.This study investigated the mechanisms of inflammatory mediator secretion and the phagocytic and bactericidal functions of mouse peritoneal macrophages following C.pseudotuberculosis infection.Initially,transcriptomic sequencing was em-ployed to identify genes critical for C.pseudotuberculosis infection in macrophages.Subsequently,gene knockout mice were utilized to assess the impact of these key genes on inflammatory media-tor secretion,activation of inflammatory signaling pathways,and the phagocytic and bactericidal functions of macrophages infected with C.pseudotuberculosis.Techniques such as ELISA,Western blot,and immunofluorescence were employed in this analysis.Further,transcriptomic sequencing was conducted to identify key downstream genes.Following C.pseudotuberculosis infection,GO enrichment analysis was performed,and TLR2 was identified as the focal point of the study.Perito-neal macrophages from C57BL/6J and TLR2 knockout(TLR2-/-)mice were infected with C.pseudotuberculosis.ELISA results revealed that the levels of TNF-α,IL-1β,and IL-10 were signifi-cantly downregulated in TLR2-/-macrophages compared to C57BL/6J macrophages post-infec-tion.Western blot demonstrated that the absence of TLR2 led to a marked decrease in M APK(p38 and ERK)signaling pathway phosphorylation following C.pseudotuberculosis infection.Immuno-fluorescence results indicated that the phagocytic rate of TLR2-/-macrophages was significantly higher than that of C57BL/6J macrophages after infection.Subsequently,transcriptomic analysis of C57BL/6J and TLR2-/-macrophages infected with C.pseudotuberculosis was performed,followed by GO enrichment analysis of differential genes.IL-36a,Cx3cr1,TLR1,and TLR2 were identified as key differential genes.TLR2 plays a crucial role in the inflammatory response induced by C.pseudotuberculosis infection in mice,influencing the progression of the inflammatory response and host outcomes through the secretion of inflammatory mediators,activation of signaling pathways,and modulation of phagocytic and bactericidal functions.IL-36a and Cx3cr1 were identified as key downstream factors in this process.

AIM:To establish a cell model of visceral hypersensitivity and nerve hyperplasia in irritable bowel syndrome(IBS)by conducting an in vitro co-culture of mouse P815 mast cells and N2a nerve cells and explore its possible mechanism.METHODS:Enzyme-linked immunosorbent assay(ELISA)with three replicates was used to confirm the C48/80-induced P815 degranulation.The length of neurites was observed under bright field microscopy to determine the number of differentiated neurons,thereby selecting the concentration of retinoic acid(RA)for stimulating the differentia-tion of N2a cells,with four replicates.A co-culture system of P815 and N2a cells was established using Transwell cham-bers with four replicates.The following groups were established:N2a cells cultured alone,N2a cells co-cultured with P815 cells,N2a cells co-cultured with P815 cells plus C48/80,and N2a cells plus RA group.After co-culturing,the num-ber of differentiated N2a cells was observed under bright field.The expression of nerve growth factor(NGF),tyrosine ki-nase receptor A(TRKA),growth-associated protein-43(GAP43),neuron-specific enolase(NSE),synapsin(SYN),and postsynaptic density protein-95(PSD-95)at both protein and gene levels in N2a cells was detected using Western blot and polymerase chain reaction(PCR),with four replicates.RESULTS:The best condition for N2a differentiation was stimulation with 10 μmol/L RA for 24 hours,whereas the best condition for degranulation was stimulation of P815 cells with 20 mg/L C48/80 for 24 hours.Compared with N2a cells cultured alone,the differentiation ratio of the N2a+P815+C48/80 and N2a+RA groups was significantly increased(P<0.01),and the protein and mRNA expressions of NGF,TRKA,GAP43,NSE,SYN,and PSD-95 were significantly increased(P<0.05).CONCLUSION:Our results revealed that mast cell degranulation enhances the level of nerve hyperplasia in enteric nerve cells and promotes changes in nerve structure and function.Synaptic remodeling regulated by abnormal expression of key proteins such as NGF,TRKA,and GAP43 is involved in the nerve hyperplasia induced by mast cell degranulation.

Exposure to acceleration can have Various effects on the physiology,psychology,and performance of human.With the increasing density and complexity of China's space mission,and the significant differences between deep space exploration and near Earth orbit flight,unprecedented challenges have been posed to the emotions of astronauts and the ability of human-machine collaboration to complete complex operational tasks in special environments.Similarly,with the continuous development of high-performance fighter jets,air combat operation are becoming increasingly complex,and the payload generated by the aircraft is also increasing.The requirements for the anti-overload ability of fighter pilots are also becoming higher and higher.A review of recent studies on physiological and cognitive load of acceleration exposure on humans.The research on human physiology is relatively systematic,but there is limited research on cognitive load.The corresponding evaluation methods,assessment methods,and assessment systems are not comprehensive enough,and there is a lack of mechanistic analysis.Multimodal analysis and modeling are even rarer.Further in-depth research is needed on the cognitive load and evaluation techniques of overweight environment in the future.This article provides reference for the selection,adaptive training,and related experimental research of overweight endurance for astronauts and pilots in the future.

Objective:To measure pancreatic fat deposition by magnetic resonance chemical shift imaging (CSI), and analyze the correlation between pancreatic fat deposition and pancreatic fistula after pancreaticoduodenectomy (PD).Methods:A retrospective analysis was conducted on the data of 55 patients who underwent PD in the Affiliated Hospital of Xuzhou Medical University from September 2021 to April 2024. Among them, 34 were male (61.8%) and 21 were female (38.2%), with the age of (63.5±12.0) years. The 55 patients included 17 cases (30.9%) of pancreatic ductal adenocarcinoma, 1 case (1.8%) of pancreatic serous cystadenoma, 2 cases (3.6%) of pancreatic mucinous cystadenoma, 1 case (1.8%) of pancreatic solid pseudopapillary tumor, 11 cases (20.0%) of ampullary carcinoma, 10 cases (18.2%) of common bile duct carcinoma, and 13 cases of other pathological types (such as high-grade intraepithelial neoplasia of the ampullary gland, duodenal adenocarcinoma, etc.) (23.6%). Before the operation, pancreatic fat deposition was measured by CSI and the fat fraction was calculated. With a fat fraction of 6.2% as the cut-off value, 55 patients were divided into the normal pancreas group (fat fraction ≤ 6.2%, n=29) and the fat pancreas group (fat fraction > 6.2%, n=26). The total hospitalization cost, postoperative hospital stay, biochemical leakage, grade B pancreatic fistula of the two groups were compared, and the correlation between pancreatic fat fraction and pancreatic fistula was analyzed. Result:The total hospitalization cost in the normal pancreas group was (91 527.3±19 118.4) yuan, and the postoperative hospital stay was 9.0 (8.0, 13.0) days, both of which were lower than those in the fatty pancreas group (107 772.4 ± 27 055.6) yuan and 11.0 (8.0, 22.0) days, and the differences were statistically significant ( t=-2.59, P=0.012; Z=-2.08, P=0.038). In the normal pancreas group, 8 cases (27.6%) of biochemical leakage and 1 case (3.4%) of grade B pancreatic fistula occurred after the operation. In the fat pancreas group, 10 cases (38.5%) of biochemical leakage and 8 cases (30.8%) of grade B pancreatic fistula occurred after the operation. There was no statistically significant difference in the incidence of biochemical leakage between the two groups ( χ2=0.74, P=0.391). The incidence of grade B pancreatic fistula after surgery in the adipose pancreas group was significantly higher than that in the normal pancreas group, and the difference was statistically significant ( χ2=5.61, P=0.018). The relationship between pancreatic body fat fraction and the occurrence of pancreatic fistula is correlated (the correlation coefficient was 0.334, 95% CI: 0.127-0.515, P=0.013) The relationship between the overall fat fraction of the pancreas and the occurrence of pancreatic fistula is correlated (the correlation coefficient was 0.472, 95% CI: 0.235-0.689, P<0.001). Conclusions:The incidence of grade B pancreatic fistula after PD in patients with a low fat fraction of the pancreas measured by CSI was lower than that in patients with a high fat fraction. Fat deposition in the pancreatic body and the pancreas as a whole is associated with the incidence of pancreatic fistula.

Objective To explore the application effect of health education based on gain and loss message framing on the treatment behavior intention and self-management of patients with high-risk diabetic foot.Methods From July to September 2024,convenience sampling was used to select patients with high-risk diabetic foot who were hospitalized in the endocrinology department of a tertiary general hospital in Guiyang as the study subjects.They were divided into 3 groups according to the admission time,with 30 patients in each group.The experimental group adopted health education based on gain message framing or framing loss message,while in the control group,health education was provided in a conventional manner.Before and after intervention,the differences of intervention effects among the 3 groups were compared by using diabetic foot pre-hospital delay intention questionnaire,diabetic foot care knowledge questionnaire and Chinese version of Nottingham foot care assessment scale(CNAFF).Results Ultimately,29 cases in the gain framing group,29 cases in the loss framing group,and 29 cases in the control group completed the study.After intervention,the score of pre-hospital delay intention questionnaire of diabetic foot in the gain framing group was(21.48±4.32),and it was(24.31±2.49)in the loss framing group,and(17.76±5.03)in the control group.The difference among the 3 groups was statistically significant(F=18.725,P＜0.001);the loss framing group was superior to the gain framing group(P=0.01)and the control group(P＜0.001).After the intervention,the score of the CNAFF in the gain framing group was(55.83±3.06),and it was(59.14±2.90)in the loss framing group,and(48.66±2.58)in the control group.The difference between the 3 groups was statistically significant(F=102.245,P＜0.001).The loss framing group was superior to the gain framing group and the control group(all P＜0.001).Conclusion Health education based on the loss message framing is more conducive to improving patients' intention to delay diabetic foot visits,leading to good foot care behaviors,and may provide an effective means of pre-hospital prevention and control of diabetic foot.

Objective:To establish and evaluated a logistic regression model for predicting the acute biliary pancreatitis (ABP) based on liver-injury related indexes.Methods:Clinical data of 210 patients diagnosed with acute pancreatitis (AP) at the Affiliated Hospital of Jiangnan University from October 2020 to December 2022 were retrospectively analyzed, including 113 males and 97 females, with a median age of 52 years (range, 43 to 58). Among these, 88 were diagnosed with ABP and 122 with acute non-biliary pancreatitis (ANBP). Additionally, a test cohort was created using data from 101 AP patients diagnosed between January and December 2023, including 60 males and 41 females, with a median age of 53 years (range, 43 to 63). Based on the original dataset, univariate and multivariate logistic regression analyses were conducted to identify the factors influencing ABP. A prediction probability formula (Pre) was then established based on the multivariate results. The effectiveness of each indicator in predicting ABP was evaluated using the receiver operating characteristic (ROC) curve. The ROC curve analysis determined the optimal cutoff value of Pre, which was subsequently used to diagnose ABP and ANBP in the test cohort.Results:Multivariate logistic regression analysis showed the factors influencing ABP include direct bilirubin (DBIL), alanine aminotransferase (ALT), aspartate aminotransferase (AST), cholinesterase (CHE), and fibrinogen (FIB). Based on the multivariate analysis results, the prediction probability formula (Pre) for ABP was established as follows: P=1/{1+ exp[-(4.807+ 0.134×DBIL-1.859×AST/ALT-0.0003×CHE-0.387×FIB)]}. ROC curve analysis revealed that the area under the curve (AUC) for Pre in predicting ABP was 0.858, with an optimal cutoff value of 0.56, at which the sensitivity was 69.3% and the specificity was 91.0%. Using the cutoff value of 0.56 for Pre, ABP was diagnosed when Pre≥0.56 and ANBP was diagnosed when Pre<0.56. This criterion was applied to diagnose patients in the test cohort, where the sensitivity and specificity of Pre for diagnosing ABP were 86.1% and 92.3%, respectively.Conclusion:The logistic regression model based on liver injury-related indicators is a valuable tool for clinically assessing the incidence of ABP.

Objective:To analyze the changes of serum metabolites in patients with acute pancreatitis (AP) by non-targeted metabolomics method.Methods:Serum samples and clinical data of 15 AP patients hospitalized in the Affiliated Hospital of Jiangnan University from August to September 2024 were collected and included in the AP group, including 9 males and 6 females, aged (55.4±15.3) years. The serum and clinical data of 25 patients with colon polyps in the same hospital during the same period of time were collected, including 15 males and 10 females, aged (61.2±11.5) years, and were included in the control group. Serum metabolomic detection was performed using the ultra-high performance liquid chromatography tandem Fourier transform mass spectrometer. The modeling method was orthogonal partial least square discriminant analysis, and principal component analysis was performed on the data matrix to screen the differential metabolites in serum of AP patients. The Kyoto Encyclopedia database of Genes and Genomes was used to annotate differential metabolites, and the pathway of differential metabolite enrichment was analyzed by software.Results:The principal component analysis showed that the contribution ratio of the first principal component was 15.1%, the proportion of the second principal component was 10.8%, and the total proportion of the two was 25.9%. In principal component analysis, two groups of samples can be clearly distinguished and show obvious clustering characteristics. According to the analysis of OPLS-DA model, there were significant differences in serum metabolic profiles between AP group and control group. There were 683 differentially expressed metabolites between the two groups, with 367 differentially expressed metabolites up-regulated compared with the control group and 316 differentially expressed metabolites down-regulated compared with the control group. It is mainly Phosphatidic Acid (Lte4/8: 0) (+ 218%), Omeprazole Sulphone (-38%), and 2-(Propylthio) Nicotinic Acid (2-propyl thionicotinic acid) (-58%), Gein (salicyricetin) (-47%) and so on. Pathway enrichment analysis showed that the differential metabolites in AP patients were mainly concentrated in citric acid cycle, arginine biosynthesis and glycerophospholipid metabolism pathways.Conclusion:Serum metabolites in AP patients change significantly, including citric acid cycle, arginine biosynthesis, glycerophospholipid metabolism.