INTRODUCTION: Obstructive sleep apnoea (OSA) is common in Singapore, with moderate to severe OSA affecting around 30% of residents. These consensus statements aim to provide scientifically grounded recommendations for the management of OSA, standar-dise the management of OSA in Singapore and promote multidisciplinary collaboration. METHOD: An expert panel, which was convened in 2024, identified several areas of OSA management that require guidance. The expert panel reviewed the current literature and developed consensus statements, which were later independently voted on using a 3-point Likert scale (agree, neutral or disagree). Consensus (total ratings of agree and neutral) was set a priori at ≥80% agreement. Any statement not reaching consensus was excluded. RESULTS: The final consensus included 49 statements that provide guidance on the screening, diagnosis and management of adults with OSA. Additionally, 23 statements on the screening, diagnosis and management of paediatric OSA achieved consensus. These 72 consensus statements considered not only the latest clinical evidence but also the benefits and harms, resource implications, feasibility, acceptability and equity impact of the recommendations. CONCLUSION The statements presented in this paper aim to guide clinicians based on the most updated evidence and collective expert opinion from sleep specialists in Singapore. These recommendations should augment clinical judgement rather than replace it. Management decisions should be individualised, taking into account the patient's clinical characteristics, as well as patient and caregiver concerns and preferences.
Humans ; Sleep Apnea, Obstructive/diagnosis* ; Singapore ; Consensus ; Adult

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.
Mesenchymal Stem Cells/cytology* ; Oxidative Stress/radiation effects* ; Animals ; Adipogenesis/radiation effects* ; Mice ; Radiation, Ionizing ; Cell Differentiation/radiation effects* ; Humans ; NF-E2-Related Factor 2/metabolism* ; PPAR gamma ; Cells, Cultured

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 (1×10⁷ per mouse) from donor mice within 4-6 hours after receiving a lethal dose (8.0 Gy, 72.76 cGy/min) of γ 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 7^th 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 PPARγ and CEBPα were detected by Western blot. The expression differences of key adipogenic transcription factors including PPARγ, 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 PPARγ and CEBPα expressed in MSCs were down-regulated. Further RT-qPCR assay showed that the production of PPARγ, 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.
Animals ; Mesenchymal Stem Cells/cytology* ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Adipogenesis ; Female ; Cell Differentiation ; Graft vs Host Disease/blood* ; Bone Marrow Cells/cytology* ; PPAR gamma/metabolism* ; Disease Models, Animal ; CCAAT-Enhancer-Binding Protein-alpha/metabolism*

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

Colitis-associated cancer(CAC)is a specific type of colorectal cancer that develops from inflammatory bowel disease(IBD).Myeloid-derived suppressor cells(MDSCs)are a group of myeloid cells with immunosuppressive properties,and MDSCs in the tumor microenvironment proliferate and activate during the development of colitis-associated cancer,inhibiting T-cell production and impairing their function,which impedes the immunotherapeutic effect of colitis-associated cancer.In this paper,we review the immunosuppressive mechanisms of MDSCs in the development of inflammatory bowel disease to colitis-associated cancers and the current drugs targeting MDSCs for immunotherapy of inflammatory colorectal cancers,with a view to providing new strategies for the treatment of colitis-associated cancers.

Objective To investigate the effects of cinbufagin(CB)on the proliferation,migration and invasion ability as well as epithelial-mesenchymal transition(EMT)of human colon cells HCT116.Methods Logarithmically grown HCT116 cells were randomly divided into blank group and experimental-L,-M,-H groups;the blank group did not receive any treatment(0 nmol·L-1),and experimental-L,-M,-H groups were cultured in 1 640 medium containing 17.5,35 and 70 nmol·L-1 cinbufagin for 48 h.Cell counting kit-8(CCK-8)was used to detect the effect of cinbufagin on the survival rate of HCT116 cells;cloning assay was used to detect the effect of cinbufagin on the proliferation of HCT116 cells;cell scratch assay and Transwell assay were used to detect the effect of cinbufagin on the migration and invasive ability of HCT116 cells;Western blot was used to detect the expression levels of janus kinase 2(JAK2)/signal transducers and activators of transcription 3(STAT3)pathway and EMT-related proteins of HCT116 cells.Results The number of clone formation in blank group and experimental-L,-M,-H groups were 122.67±24.42,73.67±15.82,44.33±4.51 and 21.67±1.53;the rates of migration of scratches were(44.64±9.15)％,(26.91±2.94)％,(19.28±1.52)％and(6.33±2.30)％;the number of invaded cells were 120.33±1.15,58.33±9.07,33.33±1.53 and 18.33±3.21;the relative protein expression of phosphorylated JAK-2(p-JAK-2)/JAK-2 were 1.02±0.06,0.94±0.05,0.75±0.22 and 0.49±0.22;relative protein expression of phosphorylated STAT3(p-STAT3)/STAT3 were 0.89±0.10,0.72±0.04,0.65±0.06 and 0.52±0.18;relative protein expression of E-cadherin were 0.30±0.14,0.41±0.13,0.49±0.14 and 0.69±0.17;relative protein expression of N-cadherin were 0.96±0.11,0.78±0.04,0.69±0.12 and 0.40±0.15;Snail relative protein expression were 0.89±0.08,0.62±0.15,0.44±0.15 and 0.27±0.09;Vimentin relative protein expression were 0.92±0.09,0.76±0.13,0.63±0.01 and 0.43±0.09,respectively.The above indexes in experimental-H group showed statistically significant differences compared to blank group(all P＜0.05).Conclusion HCT116 can inhibit the invasion and metastasis of human colorectal cancer cells HCT116 by inhibiting epithelial-mesenchymal transition through JAK2/STAT3 pathway.

Objective To explore the mechanism of inhibition of colorectal cancer cells HT29 proliferation,migration and invasion by bufalin through Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)pathway.Methods Human colorectal cancer HT29 cells were randomly divided into control group and experimental-L,-M,-H groups.The cells in the control group were not treated,and the cells in the experimental-L,-M,-H groups were treated with 2.5,5.0 and 10.0 μmol·L-1 bufalin for 48 h.After HT29 cells were infected with FLAG STAT3 lentivirus,the cells were divided into lentivirus infection group and experiment-H(10.0 pmol·L-1 bufalin)+lentivirus infection group.Cell viability was detected by cell counting kit 8(CCK-8).Cloning experiment to verify cell proliferation rate;Transwell experiment verified the migration ability of cells after bufalin treatment;the transfection efficiency of lentivirus and the expression of cell-related proteins were detected by Western blot.Results After 48 h of drug action,the number of cells in the control group,experimental-L,-M,-H groups were 1 003.25±255.53,698.00±152.25,562.13±31.56 and 449.50±82.40,respectively;the number of invasive cells were 932.00±188.84,742.22±108.64,514.67±124.82 and 343.56±86.42,respectively;the protein expression level of p-JAK2 were 1.37±0.27,0.97±0.06,0.74±0.06 and 0.39±0.12,respectively.The number of cells in the control group,experimental-H group,lentivirus infection group,and experimental-H+lentivirus infection group were 906.88±211.71,389.00±143.08,1 279.38±210.34 and 604.75±12.52,respectively;the number of invasive cells were 671.22±44.74,246.11±28.16,1 080.78±119.13 and 574.78±16.23,respectively.Compared with the control group,there were statistically significant differences in the number of cell proliferation,the number of cell invasion and the relative levels of p-JAK2 in the experimental-M and-H groups(all P＜0.05).Compared with the control group,the number of cell proliferation and the number of cell invasion in the experimental-H group,the lentivirus infection group,and the high-dose experimental+lentivirus infection group were statistically significant(all P＜0.05).Conclusion Bufalin can inhibit the proliferation,migration and invasion of colorectal cancer by activating the JAK2/STAT3 signalling pathway.

MicroRNAs(microRNAs,miRNAs)are a class of endogenous,single-stranded,short and highly conserved non-coding RNAs.miR-135b,as a member of miRNAs,is aberrantly expressed in digestive malignancies.Its mechanism of action involves a variety of target genes and participates in tumorigenesis and development by regulating cell proliferation,metastasis,and drug resistance.Clinical studies have shown that high expression of miR-135b is associated with poor patient prognosis and decreased survival.As a potential biomarker,miR-135b may be useful in the diagnosis,prognostic assessment,and therapeutic monitoring of malignant tumors of the digestive system.Therefore,miR-135b and its regulated pathways may become future therapeutic targets and provide new ideas for the treatment and management of tumor patients.

Objective To investigate the dynamic expression with the time change of N6-methyladenosine(m6A)methylation-related factors in the repair process of skeletal muscle injury and its mechanism in the inflammatory response of macrophage in the injure process.Methods In vivo mice models of BaCl2 injury in the gastrocnemius were established.Four mice per group in the control group and injury group.Gastrocnemius tissues were harvested at day 1,3,5,7,and 9 after injury for experiments.Primary gastrocnemius muscle tissue cells,muscle satellite cells,muscle cells,and cell line C2C12 cells were treated with dexamethasone(DEX,50 μmol/L)to mimic injury.Lipopolysaccharide(LPS,100 μg/L)induced RAW264.7 cell lines to mimic the inflammatory response after skeletal muscle injury,and STM2457(30 μmol/L)was added to inhibit the effect of methyltransferase 3(Mettl3)before LPS treatment.The expression of m6A methylation-related factors(Writers,Erasers,Readers)and inflammation factors were detected by Real-time PCR and Western blotting.Results The muscle fibers were dissolved and then gradually repaired with the extension of injury time,the number of monocytes/macrophages increased first and then decreased,and the Pax7 mRNA level increased first and then decreased with the change of injury time.Compared with the control group,the mRNA and protein levels of m6A methylation-related factors in gastrocnemius did not change significantly on the injury-1 day.However,they were significantly increased on the injury-3 days compared with the control group(P＜0.05),and then obviously decreased on the injury-5 days group compared with the injury-3 days group(P＜0.05).Compared with the control group,they were no significant differences on the injury-7 days group and-9 days group.In vitro DEX decreased the mRNA levels of m6A methyltransferase factors in primary muscle satellite cells and C2C12 cells and increased the mRNA expression level of methylation-recognition enzyme factors(P＜0.05).The mRNA levels of m6A methylation-related factors increased significantly in skeletal muscle tissue cells and myocytes after DEX treatment(P＜0.05).After LPS treatment,the mRNA and protein expression levels of m6A methylation-related factors and the mRNA expression levels of inflammatory factors interleukin(IL)-6 and IL-1β in macrophages increased significantly(P＜0.05),while the levels of IL-6 and IL-1β mRNA in macrophages decreased significantly when the Mettl3 was inhibited(P＜0.05).Conclusion m6A methylation-related factors primarily is activated in the damaged muscle cells and inflammation response of macrophages.Inhibition of m6A methyltransferase can reduce the inflammatory response of macrophages.

To explore the protective mechanisms of a novel molybdenum disulfide (MoS₂) nanozyme in alleviating inflammation-related endothelial cell injury by regulating mitochondrial dynamic, flower like-MoS₂ nanosheets were prepared by hydrothermal method, and its antioxidant enzyme-mimic activities were assessed via electron spin resonance (ESR) spectroscopy. It was shown that MoS₂ nanosheets had strong scavenging ability for hydroxyl radical (·OH) and singlet reactive oxygen species (¹O₂) in a dose-dependent manner. Using an in vitro lipopolysaccharide (LPS)-induced vascular endothelial cell injury model, the protective roles of MoS₂ nanozyme on cytotoxicity and apoptosis of endothelial cells were examined by MTT and Annexin V-FITC/PI assay, respectively. Mitochondrial fission/fusion of endothelial cell were observed by Mito-Tracker green probe. Reactive oxygen species (ROS) probe DCFH-DA and superoxide anion probe DHE were used to detect the level of oxidative stress in vitro. Plasmid GFP-LC3 transfection using colocalization analysis was applied to assess the autophagy of endothelial cells. The results showed that MoS₂ nanozyme could significantly reduce the cytotoxicity and apoptosis of endothelial cells stimulated by LPS, and prevent the impairment mitochondrial dynamics of endothelial cells, thus maintaining mitochondrial dynamics. In addition, MoS₂ nanozyme was also shown to alleviate LPS-mediated endothelial mitochondrial autophagy, thus protecting endothelial cells from inflammatory stress. These results established that MoS₂ nanozyme protected endothelial cells injury from inflammatory stress by regulating mitochondrial dynamics and mitochondrial autophagy of endothelial cells, which is expected to expand the use of MoS₂ nanozyme in the prevention and treatment of inflammation-related vascular endothelial diseases.