BACKGROUND:Macrophage migration inhibitory factor(MIF)is a pleiotropic cytokine,which is secreted in different types of stem cells and can regulate the proliferation,differentiation and migration of various types of stem cells.Our previous research has confirmed that human embryonic stem cells secrete MIF and that its concentration in the culture medium is relatively stable.However,whether MIF is involved in the survival,proliferation and differentiation of human embryonic stem cells remains unclear. OBJECTIVE:To investigate the effects of MIF on survival,proliferation,and differentiation of human embryonic stem cells. METHODS:(1)Human embryonic stem cells H9 were cultured.The growth curve of cells was detected and plotted by CCK-8 assay.Enzyme-linked immunosorbent assay was used to determine the level of MIF in the medium.(2)To determine the effects of exogenous MIF on the survival and proliferation of human embryonic stem cells,different groups were established:the control group,which was cultured in stem cell medium without any modifications;the exogenous MIF group,which was treated with different concentrations(30,100,300 ng/mL)of MIF in the stem cell medium;the MIF inhibitor ISO-1 group,which was treated with different concentrations(2,7,21 μmol/L)of ISO-1 in the stem cell medium;and the MIF+ISO-1 group,which was treated with different concentrations of ISO-1 along with 100 ng/mL of MIF.Cell viability was assessed using the CCK-8 assay.(3)To further elucidate the effect of MIF gene on survival and proliferation of human embryonic stem cell,the MIF knockout H9 cell line was constructed by CRISPR-Cas 9 technology to observe the lineage establishment.(4)To determine the effect of high concentrations of MIF on human embryonic stem cell differentiation,100 ng/mL MIF and 100 ng/mL of CXCR4 neutralizing antibody were separately added to the normal stem cell culture medium.The expression levels of self-renewal factors(KLF4,c-MYC,NANOG,OCT4,and SOX2)and differentiation transcription factors(FOXA2,OTX2)were measured using real-time quantitative polymerase chain reaction,immunofluorescence staining,and western blot analysis. RESULTS AND CONCLUSION:(1)The logarithmic growth phase of H9 cells was between 3-6 days.Under normal growth conditions,human embryonic stem cells secreted MIF at a concentration of approximately 20 ng/mL,independent of cell quantity.(2)Compared to the control group,the addition of different concentrations of MIF had no effect on the proliferation of human embryonic stem cells(P>0.05).ISO-1 significantly inhibited the proliferation of human embryonic stem cells,with a stronger inhibition observed at higher concentrations of ISO-1(P<0.05).The addition of MIF in the presence of ISO-1 reduced the inhibitory effect of ISO-1(P<0.05).(3)Real-time quantitative polymerase chain reaction showed that knocking out 50%of the MIF gene resulted in a significant decrease in the growth vitality of human embryonic stem cells and failure to establish cell lines.(4)Adding 100 ng/mL exogenous MIF to the culture medium resulted in a decrease in the mRNA,protein,and fluorescence expression levels of the self-renewal transcription factor KLF4,while the mRNA,protein,and fluorescence expression levels of the differentiation factor FOXA2 increased.(5)When 100 ng/mL CXCR4 neutralizing antibody was added to the culture medium,the mRNA and protein expression levels of KLF4 increased,while the mRNA and protein expression levels of FOXA2 decreased,contrary to the expression trend observed in the MIF group.In conclusion,the endogenous secretion of MIF by human embryonic stem cells is essential for their survival.The addition of MIF to the culture medium does not promote the proliferation of human embryonic stem cells.However,it can lead to a decrease in the expression of the self-renewal factor KLF4 and an increase in the expression of the transcription factor FOXA2.This provides a clue for further investigation into the effects and mechanisms of MIF on the differentiation of human embryonic stem cells.The MIF-CXCR4 axis plays a regulatory role in this process.

OBJECTIVE: To review the research progress and challenges of poly (L-lactic acid) (PLLA) membrane in preventing tendon adhesion. METHODS: The relevant literature at home and abroad in recent years was extensively searched, covering the mechanism of tendon adhesion formation, the adaptation challenge and balancing strategy of PLLA, the physicochemical modification of PLLA anti-adhesion membrane and its application in tendon anti-adhesion. In this paper, the research progress and modification strategies of PLLA membranes were systematically reviewed from the three dimensions of tissue adaptation, mechanical adaptation, and degradation adaptation. RESULTS: The three-dimensional adaptation of PLLA membrane is optimized by combining materials (such as hydroxyapatite, polycaprolactone), structural design (multilayer/gradient membrane), and drug loading (anti-inflammatory drug). The balance between anti-adhesion and pro-healing is achieved, the mechanical adaptation significantly improve, and degradation is achieved (targeting the degradation cycle to 2-4 weeks to cover the tendon repair period). CONCLUSION In the future, it is necessary to identify the optimal balance point of three-dimensional fitness, unify the evaluation criteria and solve the degradation side effects through the co-design of physicochemical modification and drug loading system to break through the bottleneck of clinical translation.
Tissue Adhesions/prevention & control* ; Polyesters/chemistry* ; Humans ; Biocompatible Materials/chemistry* ; Tendons/surgery* ; Membranes, Artificial ; Tendon Injuries/surgery* ; Wound Healing ; Animals ; Durapatite/chemistry*

Objective:To explore the feasibility of extracting the key plane of the normal fetal palate on the 11-13 + 6 week from tomography ultrasonography imaging based on artificial intelligence. Methods:The fetal volume datas of 235 cases of 11-13 + 6 week normal fetal were collected from the Department of Ultrasound in the Luohu District People′s Hospital of Shenzhen and Huazhong University of Science and Technology Union Shenzhen Hospital from May 2020 to April 2021. The data acquisition was completed by sonographers A and B by using the GE Voluson E10 color Doppler ultrasound diagnostic instrument. All datas were marked offline by sonographer C. Tomographic imaging was performed on all included data by sonographer D, the tomographic images were saved and the time-consuming was recorded, and the datas of the sonographer group were obtained. The labeled data were randomly divided into the training set and test set for model transfer learning and testing.The 4-fold cross-validation was adopted to record the test set image output by the model and the time consumption to obtain the intelligent group data. A senior sonographer performed image analysis on the two groups of data images. The feasibility of the intelligent model was verified by comparing the score of the plane of retronasal triangle(RTP), the acquisition rate of RTP, the acquisition rate of the fault, and the time-consuming difference between the sonographer group and the intelligent group. Results:①There was no significant difference in the overall distribution of RTP scores between the sonographer group and intelligent group [5 (5, 6) points vs 5 (5, 6) points, Z=0.355, P=0.722]. The RTP acquisition rate of the sonographer group and intelligent group was not statistically significant (78.72% vs 76.60%, χ 2=0.55, P=0.458). The consistency and correlation of RTP obtained by the two groups were high (Kappa=0.645, φ=0.646, both P<0.001). ②The effective layers of the sonographer group were 9 (8, 9) and the intelligent group was 8 (7, 9). The fault acquisition rate of the doctor group was higher than that of the intelligent group (78.72% vs 68.51%, χ 2=12.52, P=0.001). The consistency and correlation of the two groups in obtaining faults were media (Kappa=0.503, φ=0.521, both P<0.001). ③The time-consuming of the intelligent group was significantly lower than that of the sonographer group [1.50 (1.23, 1.75)s vs 26.94 (22.28, 30.48)s, Z=11.440, P<0.001]. Conclusions:This research model can quickly and accurately realize the extraction and tomography of the key plane of the normal fetal palate on the 11-13 + 6 week.

Objective:To explore the accuracy and clinical application value of a Multi-Agent Reinforcement Learning framework (MARL framework) in three-dimensional ultrasound to automatically locate the coronal plane of the uterus.Methods:A total of 144 female patients who underwent routine gynecological examinations in Luohu People′s Hospital during May 2020 were selected as the experimental subjects. The three-dimensional volume data of the uterus of all the experimental subjects were collected by using the Resona-8 high-end color Doppler ultrasound system. A sonographer with more than 5 years of clinical experience manually locate the coronal plane of the uterus in all collected data, and at the same time automatically locate the coronal plane of the uterus MARL framework. The coronal plane images of the uterus obtained by the two methods were saved, and the operation time of the two methods was recorded. The coronal plane uterine images obtained by the two methods were mixed together, and the images were scored 0-1 by two senior ultrasound experts in a double-blind manner. The average score greater than or equal to 0.6 points was considered qualified.Results:①In 144 volunteers, among the coronal planes of the uterus located by the two methods, 131 were qualified by the manual method, and 137 were qualified by the automatic method.There was no statistical difference between the manual and automatic coronal plane images of the uterus (χ 2=1.934, P=0.164) by the chi-square test. ②Using interquartile range analysis, the median and interquartile range of the image score of the automatic group was 0.80(0.75, 0.90), while the median and interquartile range of the image score of the manual group was 0.80(0.75, 0.90). The Wilcoxon signed rank test was used to analyze the quality of the coronal plane images obtained by manual and automatic methods, and the difference was not statistically significant ( Z=1.241, P=0.215). ③The paired t test was used to compare the time required to locate the coronal surface of the uterus, by manual method (63.65±10.182)s, by automatic method (3.25±0.294)s, the difference between the two methods was statistically significant ( t=19.52, P<0.001). Conclusions:The method based on MARL framework has a high correlation with the manual locating of the coronal plane of uterus in three-dimensional ultrasound, and greatly reduces the operation time. It can be effectively applied in clinical practice and lays a foundation for the automatic diagnosis of uterine related diseases.

[Abstract] Objective: To explore the role of adhesion molecule with Ig like domain 2 (AMIGO2) in the proliferation of nasopharyn‐ geal carcinoma (NPC) cells and its mechanisms. Methods: A total of 10 NPC tissue samples and 10 normal nasopharyngeal epithelial tissue samples collected at Fujian Cancer Hospital during September 2017 and November 2017 were used for this study; in addition, NPC cell lines (CNE-1, CNE-2, SUNE-1, 6-10B, C666-1) and human immobilized nasopharyngeal epithelial cell line NP69 were also collected. The relative expression of AMIGO2 mRNAin above mentioned tissues and cell lines was detected by qPCR. Lentivirus vectors were constructed to interfere AMIGO2 mRNA expression, and qPCR was used to verify its interference efficiency. CCK-8 method, Clonal formation and Flow cytometry were performed to evaluate the effect of AMIGO2 interference on proliferation, clone formation and apoptosis of NPC cells. The influence of AMIGO2 interference on PI3K/AKT/mTOR signaling pathway and proliferation related molecular markers in NPC cells was assessed by Western blotting. Results: The results of qPCR showed that AMIGO2 was highly expressed in NPC tissues, CNE-2, and SUNE-1 cells (all P<0.01). The interference efficiency of AMIGO2 in CNE-2 and SUNE-1 cells could reach over 50%. The interfering of AMIGO2 expression significantly inhibited the proliferation and clone formation of CNE-2 and SUNE-1 cells (all P<0.01), promoted cell apoptosis (all P<0.01), reduced the phosphorylated protein expression levels of PI3K, AKT and mTOR in SUNE-1 cells (all P<0.01), as well as down-regulated the protein expressions of survivin and PCNA (all P<0.01). Conclusion: AMIGO2 may promote the proliferation as well as inhibit apoptosis of NPC cells by activating the PI3K/AKT/mTOR signaling pathway, suggesting that AMIGO2 may be a potential target for NPC therapy.