Objective or Background: Dental caries is still one of the most significant dental problems worldwide, with prevalence rates up to 90% among children and adults. Cariogenic bacteria, especially Streptococcus mutans, is the primary microorganism involved in the pathogenesis through carbohydrate metabolism and biofilm formation, which are challenging to eradicate. Histatin-5 (HST-5), a human salivary antimicrobial peptide, has demonstrated antimicrobial activity against various fungal and bacterial pathogens. Phytosphingosine (PHS), an endogenous bioactive sphingolipid found in fungi, plants, and humans, also shows antimicrobial properties. This study aimed to evaluate the killing activity of HST-5 alone and in combination with PHS against S. mutans under biofilm-stimulating conditions. Materials and Methods: Antimicrobial activity against a planktonic culture of S. mutans was evaluated using a time-kill assay, and biofilm-forming capacity was confirmed by crystal violet staining assay. The killing ability against 24h pre-formed biofilm was determined using Transferable Solid Phase (TSP) pin lid model. Synergistic activity between HST-5 and PHS was evaluated using the checkerboard technique. Additionally, the cytotoxicity of the tested agent on human gingival fibroblast cells (hGFs) was assessed after 1 h of incubation using an MTT assay. Results: A time-kill assay revealed that both HST-5 and PHS exhibit time- and concentration-dependent activity against the planktonic form of S. mutans. PHS achieved over 90% killing activity within 15 min at 5 μg/ml, whereas HST-5 required 30 min to reach 90% killing at 20 μM. The biofilm formation capacity of S. mutans was confirmed. The inhibitory concentrations (IC50) of HST-5 and PHS against S. mutans biofilm were 25 μM and 13.5 μg/ml, respectively. A synergistic interaction between HST-5 and PHS, with IC50 values reduced by 8-fold and 16-fold, respectively. No cytotoxic effects were observed in hGFs cells at the concentration of the synergistic interaction. Conclusions: Therefore, the combination of HST-5 and PHS may enhance the effectiveness of anti-infective agents against S. mutans biofilm, potentially preventing the development of dental caries.
Dental caries is still one of the most significant dental problems worldwide, with prevalence rates up to 90% among children and adults. Cariogenic bacteria, especially Streptococcus mutans, is the primary microorganism involved in the pathogenesis through carbohydrate metabolism and biofilm formation, which are challenging to eradicate. Traditional preventions like brushing, while helpful, struggle to fully eradicate this resilient bacteria’s biofilm, as once it is formed, simple brushing is not enough.
คณะเทคโนโลยีการเกษตร
This study examines the effects of chemical mutagens, ethyl methane sulfonate (EMS) and colchicine in inducing mutations in Chrysanthemum spp. through tissue culture techniques. In vitro cultures of Chrysanthemum were treated with various concentrations of EMS and colchicine to assess their impact on shoot regeneration and mutation frequency. Results indicated that EMS significantly increased phenotypic variability, leading to enhanced flower color and size, while colchicine treatment effectively induced polyploidy, resulting in plants with greater flower size and overall vigor. Morphological assessments, along with genetic analyses using molecular markers, confirmed the mutations associated with these treatments. The integration of chemical mutagenesis with tissue culture presents a promising approach for developing novel Chrysanthemum varieties with improved ornamental traits.
คณะบริหารธุรกิจ
BrushXchange is a toothbrush brand dedicated to reducing plastic waste in Thailand by offering toothbrushes made from recycled plastic with replaceable bristles. These products help minimize waste generated by traditional toothbrushes. The design is modern and user-friendly, emphasizing durability, comfort, and affordability, making it appropriate for health-conscious and environmentally aware consumers. The brand aims to drive change in the oral care industry by providing high-quality products at accessible prices. Its marketing strategy focuses on using social media platforms like Instagram and TikTok and collaborating with organizations that promote sustainability. The product is distributed through retail stores such as Lotus’s and Tops. BrushXchange also prioritizes environmental responsibility by using recycled paper packaging and organizing sustainability campaigns. The brand's long-term goal is to become a widely recognized brand image in the eco-friendly toothbrush market in Thailand while encouraging sustainable living habits within society.
วิทยาลัยอุตสาหกรรมการบินนานาชาติ
The capture of a target spacecraft by a chaser is an on-orbit docking operation that requires an accurate, reliable, and robust object recognition algorithm. Vision-based guided spacecraft relative motion during close-proximity maneuvers has been consecutively applied using dynamic modeling as a spacecraft on-orbit service system. This research constructs a vision-based pose estimation model that performs image processing via a deep convolutional neural network. The pose estimation model was constructed by repurposing a modified pretrained GoogLeNet model with the available Unreal Engine 4 rendered dataset of the Soyuz spacecraft. In the implementation, the convolutional neural network learns from the data samples to create correlations between the images and the spacecraft’s six degrees-of-freedom parameters. The experiment has compared an exponential-based loss function and a weighted Euclidean-based loss function. Using the weighted Euclidean-based loss function, the implemented pose estimation model achieved moderately high performance with a position accuracy of 92.53 percent and an error of 1.2 m. The in-attitude prediction accuracy can reach 87.93 percent, and the errors in the three Euler angles do not exceed 7.6 degrees. This research can contribute to spacecraft detection and tracking problems. Although the finished vision-based model is specific to the environment of synthetic dataset, the model could be trained further to address actual docking operations in the future.