PURPOSE: The purpose of this clinical study was to formulate a custom-made, 2-color chewing gum for the mixing ability test and to develop an image-processing method for color mixing analysis.
MATERIAL AND METHODS: Specimens of red-green (RG) chewing gum were prepared as a test food. Twenty dentate participants (10 men, 10 women; mean age 21 years) took part in this study. Each participant masticated 1 piece of RG gum for 3, 6, 9, 15, and 25 cycles, and this task was repeated 3 times consecutively (total n=15 for each participant). The boluses were retrieved and flattened to 1-mm-thick wafers and scanned with a flatbed scanner. The digital images were analyzed using ImageJ software equipped with a custom-built plug-in to measure the geometric dispersion (GD) of baseline red segment. The predictive criterion validity of this method was determined by correlating GD to the number of mastication cycles. The hardness and mass of RG chewing gum were measured before and after mastication. Hardness loss (%) and mass loss (%) were then calculated and compared with those of a commercially available chewing gum.
RESULTS: The 2-way repeated-measures ANOVA with post hoc Bonferroni test showed that GD was able to discriminate among the groups of different numbers of mastication cycles (P
METHOD: The extracts were prepared using Soxhlet apparatus for ethanol and hexane extracts while the water extracts were freeze-dried. In vitro cytotoxic activities of B. frutescens extracts of various concentrations (20 to 160 μg/mL) at 24, 48, and 72 hours time points were studied using MTT in chemically induced hypoxic condition and in 3-dimensional in vitro cell culture system. An initial characterisation of B. frutescens extracts was carried out using Fourier-transform Infrared- Attenuated Total Reflection (FTIR-ATR) to determine the presence of functional groups.
RESULTS: All leaf extracts except for water showed IC50 values ranging from 23 -158 μg/mL. Hexane extract showed the lowest IC50 value (23 μg/mL), indicating its potent cytotoxic activity. Among the branch extracts, only the 70% ethanolic extract (B70) showed an IC50 value. The hexane leaf extract tested on 3- dimensional cultured cells showed an IC50 value of 17.2 μg/mL. The FTIR-ATR spectroscopy analysis identified various characteristic peak values with different functional groups such as alcohol, alkenes, alkynes, carbonyl, aromatic rings, ethers, ester, and carboxylic acids. Interestingly, the FTIR-ATR spectra report a complex and unique profile of the hexane extract, which warrants further investigation.
CONCLUSION: Adaptation of tumour cells to hypoxia significantly contributes to the aggressiveness and chemoresistance of different tumours. The identification of B. frutescens and its possible role in eliminating breast cancer cells in hypoxic conditions defines a new role of natural product that can be utilised as an effective agent that regulates metabolic reprogramming in breast cancer.
METHODS: The decellularization was achieved using a developed closed sonication treatment system for 10 hrs, and continued with a washing process for 5 days. For the control, a simple immersion treatment was set as a benchmark to compare the decellularization efficiency. Histological and biochemical assays were conducted to investigate the cell removal and retention of the vital extracellular matrix. Surface ultrastructure of the prepared scaffolds was evaluated using scanning electron microscope at 5,000× magnification viewed from cross and longitudinal sections. In addition, the biomechanical properties were investigated through ball indentation testing to study the stiffness, residual forces and compression characteristics. Statistical significance between the samples was determined with p-value =0.05.
RESULTS: Histological and biochemical assays confirmed the elimination of antigenic cellular components with the retention of the vital extracellular matrix within the sonicated scaffolds. However, there was a significant removal of sulfated glycosaminoglycans. The surface histoarchitecture portrayed the preserved collagen fibril orientation and arrangement. However, there were minor disruptions on the structure, with few empty micropores formed which represented cell lacunae. The biomechanical properties of bioscaffolds showed the retention of viscoelastic behavior of the scaffolds which mimic native tissues. After immersion treatment, those scaffolds had poor results compared to the sonicated scaffolds due to the inefficiency of the treatment.
CONCLUSION: In conclusion, this study reported that the closed sonication treatment system had high capabilities to prepare ideal bioscaffolds with excellent removal of cellular components, and retained extracellular matrix and biomechanical properties.