OBJECTIVE: To prepare clinical-grade human umbilical cord-derived mesenchymal stem cells (hUC-MSC) with high expression of hematopoietic supporting factors and evaluate their stem cell characteristics. METHODS: Fetal umbilical cord tissues were collected from healthy postpartum women during full-term cesarean section. Wharton's jelly was mechanically separated and hUC-MSCs were obtained by explant culture method and enzyme digestion method in an animal serum-free culture system with addition of human platelet lysate. The phenotypic characteristics of hUC-MSCs obtained by two methods were detected by flow cytometry. The differences in proliferation ability between the two groups of hUC-MSCs were identified through CCK-8 assay and colony forming unit-fibroblast (CFU-F) assay. The differences in multilineage differentiation potential between the two groups of hUC-MSCs were identified through induction of adipogenic, osteogenic, and chondrogenic differentiation. The mRNA expression levels of hematopoietic supporting factors such as SCF, IL-3, CXCL12, VCAM1 and ANGPT1 in the two groups of hUC-MSCs were identified by real-time fluorescence quantiative PCR(RT-qPCR). RESULTS: The results of flow cytometry showed that hUC-MSCs obtained by the two methods both expressed high levels of CD73, CD90 and CD105, while lowly expressed CD31, CD45 and HLA-DR. The results of CCK-8 and CFU-F assay showed that the proliferation ability of hUC-MSCs obtained by explant culture method was better than those obtained by enzyme digestion method. The results of the triple lineage differentiation experiment showed that there was no significant difference in multilineage differentiation potential between the two grous of hUC-MSCs. The results of RT-qPCR showed that the mRNA expression levels of hematopoietic supporting factors SCF, IL-3, CXCL12, VCAM1 and ANGPT1 in hUC-MSCs obtained by explant cultrue method were higher than those obtained by enzyme digestion method. CONCLUSION Clinical-grade hUC-MSCs with high expression levels of hematopoietic supporting factors were successfully cultured in an animal serum-free culture system.
Humans ; Mesenchymal Stem Cells/metabolism* ; Umbilical Cord/cytology* ; Cell Differentiation ; Female ; Cell Proliferation ; Cells, Cultured ; Chemokine CXCL12/metabolism* ; Angiopoietin-1/metabolism* ; Vascular Cell Adhesion Molecule-1/metabolism* ; Stem Cell Factor/metabolism* ; Flow Cytometry ; Pregnancy

Glutamine provides carbon and nitrogen to support the proliferation of cancer cells. However, the precise reason why cancer cells are particularly dependent on glutamine remains unclear. In this study, we report that glutamine modulates the tumor suppressor F-box and WD repeat domain-containing 7 (FBW7) to promote cancer cell proliferation and survival. Specifically, lysine 604 (K604) in the sixth of the 7 substrate-recruiting WD repeats of FBW7 undergoes glutaminylation (Gln-K604) by glutaminyl tRNA synthetase. Gln-K604 inhibits SCFFBW7-mediated degradation of c-Myc and Mcl-1, enhances glutamine utilization, and stimulates nucleotide and DNA biosynthesis through the activation of c-Myc. Additionally, Gln-K604 promotes resistance to apoptosis by activating Mcl-1. In contrast, SIRT1 deglutaminylates Gln-K604, thereby reversing its effects. Cancer cells lacking Gln-K604 exhibit overexpression of c-Myc and Mcl-1 and display resistance to chemotherapy-induced apoptosis. Silencing both c-MYC and MCL-1 in these cells sensitizes them to chemotherapy. These findings indicate that the glutamine-mediated signal via Gln-K604 is a key driver of cancer progression and suggest potential strategies for targeted cancer therapies based on varying Gln-K604 status.
Glutamine/metabolism* ; Myeloid Cell Leukemia Sequence 1 Protein/genetics* ; Humans ; Proto-Oncogene Proteins c-myc/genetics* ; Cell Proliferation ; Signal Transduction ; Neoplasms/pathology* ; F-Box-WD Repeat-Containing Protein 7/genetics* ; Cell Survival ; Cell Line, Tumor ; Apoptosis

Objective:To analyze the current policy design of outpatient benefit policies for patients with hypertension and diabetes(H&D)in urban and rural residents in China,and to provide references for optimizing the outpatient benefit mechanism for patients with H&D.Methods:A questionnaire survey was conducted to collect data on the basic features of General Outpatient Benefit(GOB),Outpatient Medication Guarantee Mechanisms for Hypertension and Diabetes(OMGM-H&D)and Outpatient Benefit for Patient with Chronic and Special Diseases(OB-C&S),focusing on deductibles,policy reimbursement ratios,and maximum payment limits.Descriptive statistical analysis was performed on the data.Results:A total of 334 regions were surveyed,of which 253 regions(75.34％)had implemented all three policies.Regional analysis revealed significant differences(P<0.001)in reimbursement ratios for GOB and the OMGM-H&D between the eastern,central,and western regions,with the western region having notably higher ratios than the eastern and central regions.However,no significant difference (P>0.05) was observed in the reimbursement ratios for OB-C&S across regions. Regarding deductibles,no significant regional difference (P>0.05) was found for GOB,but significant differences (P<0.05) existed for the OMGM-H&D and OB-C&S. Additionally,the annual maximum payment limits for all three policies showed significant regional variations (P<0.001). Conclusions:The outpatient benefits policy for patients with H&D have achieved full coverage nationwide among urban and rural residents in China,but regional equity in benefit levels requires improvement. It is recommended to strengthen data feedback mechanisms and promote provincial-level pooling of medical insurance.

Microphthalmos is a congenital ocular developmental anomaly that manifests as a significant reduction in the size of eyes,and is often combined with various ocular disorders such as cataract.Due to its special intraocular anatomical features,the risk of intraoperative and postoperative complications of cataract surgery in microphthalmos is usually high.Combined with subscleral sclerectomy,peripheral iridectomy,and anterior segment vitrectomy,the incidence of the pre-existing complications in cataract surgery has decreased,meanwhile,the additional procedures may also bring new complications.In-depth understanding of the research progress of cataract surgery in microphthalmos and the prevention of complications is of great guiding significance to improve surgical outcomes,and can reduce the incidence of postoperative complications such as uveal effusion syndrome,secondary glaucoma and corneal edema,and promote personalized treatments for microphthalmos patients who suffered from cataract.

Objective:To analyze the current policy design of outpatient benefit policies for patients with hypertension and diabetes(H&D)in urban and rural residents in China,and to provide references for optimizing the outpatient benefit mechanism for patients with H&D.Methods:A questionnaire survey was conducted to collect data on the basic features of General Outpatient Benefit(GOB),Outpatient Medication Guarantee Mechanisms for Hypertension and Diabetes(OMGM-H&D)and Outpatient Benefit for Patient with Chronic and Special Diseases(OB-C&S),focusing on deductibles,policy reimbursement ratios,and maximum payment limits.Descriptive statistical analysis was performed on the data.Results:A total of 334 regions were surveyed,of which 253 regions(75.34％)had implemented all three policies.Regional analysis revealed significant differences(P<0.001)in reimbursement ratios for GOB and the OMGM-H&D between the eastern,central,and western regions,with the western region having notably higher ratios than the eastern and central regions.However,no significant difference (P>0.05) was observed in the reimbursement ratios for OB-C&S across regions. Regarding deductibles,no significant regional difference (P>0.05) was found for GOB,but significant differences (P<0.05) existed for the OMGM-H&D and OB-C&S. Additionally,the annual maximum payment limits for all three policies showed significant regional variations (P<0.001). Conclusions:The outpatient benefits policy for patients with H&D have achieved full coverage nationwide among urban and rural residents in China,but regional equity in benefit levels requires improvement. It is recommended to strengthen data feedback mechanisms and promote provincial-level pooling of medical insurance.

Microphthalmos is a congenital ocular developmental anomaly that manifests as a significant reduction in the size of eyes,and is often combined with various ocular disorders such as cataract.Due to its special intraocular anatomical features,the risk of intraoperative and postoperative complications of cataract surgery in microphthalmos is usually high.Combined with subscleral sclerectomy,peripheral iridectomy,and anterior segment vitrectomy,the incidence of the pre-existing complications in cataract surgery has decreased,meanwhile,the additional procedures may also bring new complications.In-depth understanding of the research progress of cataract surgery in microphthalmos and the prevention of complications is of great guiding significance to improve surgical outcomes,and can reduce the incidence of postoperative complications such as uveal effusion syndrome,secondary glaucoma and corneal edema,and promote personalized treatments for microphthalmos patients who suffered from cataract.

Objective:To investigate the effects and underlying mechanism of ionizing radiation on the adipogenic of mesenchymal stem cells(MSCs).Methods:Mouse MSCs were cultured in vitro and treated with 2 Gy and 6 Gy radiation with 60Co,and the radiation dose rate was 0.98 Gy/min.Bulk RNA-seq was performed on control and irradiated MSCs.The changes of adipogenic differentiation and oxidative stress pathways of MSC were revealed by bioinformatics analysis.Oil Red O staining was used to detect the adipogenic differentiation ability of MSCs in vitro,and real-time fluorescence quantitative PCR(qPCR)was used to detect the expression differences of key regulatory factors Cebpa,Lpl and Pparg after radiation treatment.At the same time,qPCR and Western blot were used to detect the effect of inhibition of Nrf2,a key factor of antioxidant stress pathway,on the expression of key regulatory factors of adipogenesis.Moreover,the species conservation of the irradiation response of human bone marrow MSCs and mouse MSC was determined by qPCR.Results:Bulk RNA-seq suggested that ionizing radiation promotes adipogenic differentiation of MSCs and up-regulation of oxidative stress-related genes and pathways.The results of Oil Red O staining and qPCR showed that ionizing radiation promoted the adipogenesis of MSCs,with high expression of Cebpa,Lpl and Pparg,as well as oxidative stress-related gene Nrf2.Nrf2 pathway inhibitors could further enhance the adipogenesis of MSCs in bone marrow after radiation.Notably,the similar regulation of oxidative pathways and enhanced adipogenesis post irradiation were observed in human bone marrow MSCs.In addition,irradiation exposure led to up-regulated mRNA expression of interleukin-6 and down-regulated mRNA expression of colony stimulating factor 2 in human bone marrow MSCs.Conclusion:Ionizing radiation promotes adipogenesis of MSCs in mice,and oxidative stress pathway participates in this effect,blocking Nrf2 further promotes the adipogenesis of MSCs.Additionally,irradiation activates oxidative pathways and promotes adipogenic differentiation of human bone marrow MSCs.

Objective:To establish an in vitro cell model simulating acute graft-versus-host disease(aGVHD)bone marrow microenvironment injury with the advantage of mouse serum of aGVHD model and explore the effect of serum of aGVHD mouse on the adipogenic differentiation ability of mesenchymal stem cells(MSCs).Methods:The 6-8-week-old C57BL/6N female mice and BALB/c female mice were used as the donor and recipient mice of the aGVHD model,respectively.Bone marrow transplantation(BMT)mouse model(n=20)was established by being injected with bone marrow cells(1 × 10'per mouse)from donor mice within 4-6 hours after receiving a lethal dose(8.0 Gy,72.76 cGy/min)of y ray general irradiation.A mouse model of aGVHD(n=20)was established by infusing a total of 0.4 ml of a mixture of donor mouse-derived bone marrow cells(1 × 107 per mouse)and spleen lymphocytes(2 × 106 per mouse).The blood was removed from the eyeballs and the mouse serum was aspirated on the 7th day after modeling.Bone marrow-derived MSCs were isolated from 1-week-old C57BL/6N male mice and incubated with 2％,5％and 10％BMT mouse serum and aGVHD mouse serum in the medium,respectively.The effect of serum in the two groups on the in vitro adipogenic differentiation ability of mouse MSCs was detected by Oil Red O staining.The expression levels of related proteins PPARy and CEBPα were detected by Western blot.The expression differences of key adipogenic transcription factors including PPARy,CEBPα,FABP4 and LPL were determined by real-time quantitative PCR(RT-qPCR).Results:An in vitro cell model simulating the damage of bone marrow microenvironment in mice with aGVHD was successfully established.Oil Red O staining showed that the number of orange-red fatty droplets was significantly reduced and the adipogenic differentiation ability of MSC was impaired at aGVHD serum concentration of 10％compared with BMT serum.Western blot experiments showed that adipogenesis-related proteins PPARy and CEBPα expressed in MSCs were down-regulated.Further RT-qPCR assay showed that the production of PPARy,CEBPα,FABP4 and LPL,the key transcription factors for adipogenic differentiation of MSC,were significantly reduced.Conclusion:The adipogenic differentiation capacity of MSCs is inhibited by aGVHD mouse serum.

OBJECTIVE: To investigate the mechanism of induction of ferroptosis by brazilin in breast cancer cells. METHODS: Breast cancer 4T1 cells were divided into 6 groups: control, brazilin 1/2 half maximal inhibitory concentration (IC₅₀), IC₅₀, 2×IC₅₀, erastin (10 µg/mL) and capecitabine (10 µg/mL) groups. The effect of brazilin on the proliferation of 4T1 cells was detected by cell counting kit-8 assay, and the treatment dose of brazilin was screened. The effect of brazilin on the mitochondrial morphology of 4T1 cells, and the mitochondrial damage was evaluated under electron microscopy. The levels of Fe²⁺, reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH) and glutathione peroxidase 4 (GPX4) were estimated using various detection kits. The invasion and migration abilities of 4T1 cells were detected by scratch assay and transwell assay. The expressions levels of tumor protein p53, solute carrier family 7 member 11 (SLC7A11), GPX4 and acyl-CoA synthetase long-chain family member 4 (ACSL4) proteins were quantified by Western blot assay. RESULTS: Compared to the control group, the 10 (1/2 IC₅₀), 20 (IC₅₀) and 40 (2×IC₅₀) µg/mL brazilin, erastin, and capecitabine groups showed a significant decrease in the cell survival rate, invasion and migration abilities, GSH, SLC7A11 and GPX4 protein expression levels, and mitochondrial volume and ridge (P<0.05), and a significant increase in the mitochondria membrane density, Fe²⁺, ROS and MDA levels, and p53 and ACSL4 protein expression levels (P<0.05). CONCLUSIONS Brazilin actuated ferroptosis in breast cancer cells, and the underlying mechanism is mainly associated with the p53/SLC7A11/GPX4 signaling pathway.
Ferroptosis/drug effects* ; Phospholipid Hydroperoxide Glutathione Peroxidase/metabolism* ; Breast Neoplasms/drug therapy* ; Signal Transduction/drug effects* ; Female ; Cell Line, Tumor ; Tumor Suppressor Protein p53/metabolism* ; Amino Acid Transport System y+/metabolism* ; Humans ; Reactive Oxygen Species/metabolism* ; Animals ; Mice ; Cell Proliferation/drug effects* ; Mitochondria/metabolism* ; Coenzyme A Ligases/metabolism* ; Cell Movement/drug effects* ; Benzopyrans

Objective To apply a COMSOL-based finite element analysis method to investigating the electric field effects produced by the human lower limb musculoskeletal system under the synergistic effects of stress field and electromagnetic field.Methods Firstly,a 3D human body model was constructed by Maxon Cinema 4D R21 software,and then imported into COMSOL 6.1 software in STL format.Secondly,an electromagnetic field intervention and stress loading model for the left lower limb of the human body was designed and constructed,in which 15 Hz quasi-pulse group current signals were used for electromagnetic field excitation and the stress field was realized by applying a vibration load with an average compressive force of about 90 N/cm2 to the left foot of the human body.Finally,the electromagnetic properties of human tissue were simulated by numerical simulation,and then the effects of stress field or elecromagnetic field or combined stress field and electromagnetic field on human bioelectric field were compared.Results Simulation results showed that the electric field intensity peaked at the leg joints under both electromagnetic and stress fields acting alone or synergistically,the bioelectric field intensity generated by the human body was related to the distance from the exogenous excitation loading location,and the electric field generated under synergistic action was equivalent to the linear superposition of the bioelectric field in the tissue induced by the electromagnetic field and the stress field acting alone.Conclusion Data supplement is provided for predicting bioelectric field changes within the musculoskeletal tissue,and theoretical foundation is laid for the development and application of multi-physics field synergistic intervention therapy for treating the disorders of the lower limb musculos-keletal system.[Chinese Medical Equipment Journal,2024,45(9):21-26]