METHODS: Mesenchymal stem cells (MSCs) from PDL tissue were isolated from human premolars (n = 3). The MSCs' identity was confirmed by immunophenotyping and trilineage differentiation assays. Cell proliferation activity was assessed through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Polymerase chain reaction array was used to profile the expression of 84 growth factor-associated genes. Pathway analysis was used to identify the biologic functions and canonic pathways activated by ASA treatment. The osteogenic potential was evaluated through mineralization assay.
RESULTS: ASA at 1,000 μM enhances osteogenic potential of PDLSCs. Using a fold change (FC) of 2.0 as a threshold value, the gene expression analyses indicated that 19 genes were differentially expressed, which includes 12 upregulated and seven downregulated genes. Fibroblast growth factor 9 (FGF9), vascular endothelial growth factor A (VEGFA), interleukin-2, bone morphogenetic protein-10, VEGFC, and 2 (FGF2) were markedly upregulated (FC range, 6 to 15), whereas pleotropin, FGF5, brain-derived neurotrophic factor, and Dickkopf WNT signaling pathway inhibitor 1 were markedly downregulated (FC 32). Of the 84 growth factor-associated genes screened, 35 showed high cycle threshold values (≥35).
CONCLUSIONS: ASA modulates the expression of growth factor-associated genes and enhances osteogenic potential in PDLSCs. ASA upregulated the expression of genes that could activate biologic functions and canonic pathways related to cell proliferation, human embryonic stem cell pluripotency, tissue regeneration, and differentiation. These findings suggest that ASA enhances PDLSC function and may be useful in regenerative dentistry applications, particularly in the areas of periodontal health and regeneration.
METHODOLOGY: The English version of the M-CHAT-R/F was translated into Malay using forward and backward translation methods. Content and face validity were ascertained and a pilot study was performed for internal reliability. A total of 244 children attending clinics and wards in UKM hospitals aged 16-30 months were recruited based on three categories: children with typical development, suspected cases, and established cases of ASD. All caregivers of the recruited children were asked to complete the Malay M-CHAT-R/F. Reliability and validation assessments were performed.
RESULTS: Malay M-CHAT-R/F was found to be a reliable tool with good internal consistency (Cronbach's alpha = 0.906, p < 0.001). The Receiver Operating Characteristic (ROC) curve showed that cut-off scores of 2 on Malay M-CHAT-R/F lead to successful ASD classification with Area Under the Curve (AUC) = 0.887, p < 0.001 with a 95% CI (0.840, 0.933).
DISCUSSION: The assessment of the Malay M-CHAT-R/F showed satisfactory psychometric properties. Based on this study, the Malay M-CHAT-R/F is a reliable and valid screening tool to screen for ASD in children aged 16-30 months. Translating the M-CHAT-R/F into Malay is expected to improve community outreach and screening, which is essential for early diagnosis and timely intervention for children with ASD in Malaysia.