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The objective of this study was to fabricate an anthropomorphic multimodality pelvic phantom to evaluate a deep-learning-based synthetic computed tomography (CT) algorithm for magnetic resonance (MR)-only radiotherapy.Polyurethane-based and silicone-based materials with various silicone oil concentrations were scanned using 0.35 T MR and CT scanner to determine the tissue surrogate. Five tissue surrogates were determined by comparing the organ intensity with patient CT and MR images. Patient-specific organ modeling for three-dimensional printing was performed by manually delineating the structures of interest. The phantom was finally fabricated by casting materials for each structure. For the quantitative evaluation, the mean and standard deviations were measured within the regions of interest on the MR, simulation CT (CTFor the prostate site, the mean MR intensities for the patient and phantom were 78.1 ± 13.8 and 86.5 ± 19.3, respectively. The mean intensity of the synthetic image was 30.9 Hounsfield unit (HU), which was comparable to that of the real CT phantom image. The original and synthetic CT intensities of the fat tissue in the phantom were -105.8 ± 4.9 HU and -107.8 ± 7.8 HU, respectively. For the target volume, the difference in DThis work demonstrated that the anthropomorphic phantom was physiologically and geometrically similar to the patient organs and was employed to quantitatively evaluate the deep-learning-based synthetic CT algorithm.

Highlights • A numerical method is presented for the acoustic vaporization threshold of microdroplets by improving the Rayleigh-Plesset equation to properly treat the supercritical state occurring at rapid bubble collapse. • The van der Waals equation of state is employed to more accurately consider the supercritical state instead of the ideal gas equation. • The effective ADV threshold is observed to increase as the acoustic frequency increases and the droplet radius decreases, as experimentally observed in the previous studies. • The present numerical predictions of ADV threshold comparable to the experimental data., A numerical model is presented for the acoustic vaporization threshold of a dodecafluoropentane (or perfluoropentane) microdroplet. The model is based on the Rayleigh-Plesset equation and is improved by properly treating the supercritical state that occurs when a bubble collapses rapidly and by employing the van der Waals equation of state to consider the supercritical state. The present computations demonstrate that the microdroplet vaporization behavior depends intricately on bubble compressibility, liquid inertia and phase-change heat transfer under acoustic excitation conditions. We present acoustic pressure-frequency diagrams for bubble growth regimes and the ADV threshold conditions. The effects of acoustic parameters, fluid properties and the droplet radius on the ADV threshold are investigated.

Acoustically-triggered droplet vaporization (ADV) in a tube is numerically studied by extending a level-set method to determine the bubble-droplet interface as well as the droplet-ambient liquid interface and to include droplet evaporation and bubble compressibility effects. The Rayleigh-Plesset equation for ADV in a tube is improved by correctly evaluating the transition from spherical to tube flows. The computations of ADV show that the liquid pressure variation along the tube caused by droplet vaporization and bubble condensation is an important factor determining bubble survival and growth. The influence of tube radius on bubble growth in ADV is quantified in various acoustic amplitude and frequency conditions. Computations are also performed to investigate bubble-bubble interaction in acoustic vaporization of two droplets.

The major function of adipocytes is to store fat in the form of triglycerides. One of the signaling pathways known to affect adipogenesis, i.e. fat formation, is the WNT/β-catenin pathway which inhibits the expression and activity of key regulators of adipogenesis. The purpose of this research is to find genes among the WNT/β-catenin pathway which regulate adipogenesis by using small interfering (si) RNA and to find the association of single nucleotide polymorphisms (SNPs) of the gene with serum triglyceride levels in the human population. To elucidate the effects of β-catenin siRNA on adipogenesis key factors, PPARγ and C/EBPα, we performed real-time PCR and western blotting experiments for the analyses of mRNA and protein levels. It was found that the siRNA-mediated knockdown of β-catenin upregulates adipogenesis key factors. However, upstream regulators of the WNT/β -catenin pathway, such as DVL2 and LRP6, had no significant effects compared to β-catenin. These results indicate that β-catenin is a candidate gene for human fat accumulation. In general, serum triglyceride level is a good indicator of fat accumulation in humans. According to statistical analyses of the association between serum triglyceride level and SNPs of β-catenin, -10,288 C>T SNP (rs7630377) in the promoter region was significantly associated with serum triglyceride levels (p

SH21B is a natural composition composed of seven herbs: Scutellaria baicalensis Georgi, Prunus armeniaca Maxim, Ephedra sinica Stapf, Acorus gramineus Soland, Typha orientalis Presl, Polygala tenuifolia Willd and Nelumbo nucifera Gaertner (Ratio 3:3:3:3:3:2:2). In our previous study, we reported that SH21B inhibited adipogenesis and fat accumulation in 3T3-L1 cells through modulation of various regulators in the adipogenesis pathway. The aim of this study was to analyze the transcriptome profiles for the anti-adipogenic effects of SH21B in 3T3-L1 cells. Total RNAs from SH21B-treated 3T3-L1 cells were reverse-transcribed into cDNAs and hybridized to Affymetrix Mouse Gene 1.0 ST array. From microarray analyses, we identified 2,568 genes of which expressions were changed more than two-fold by SH21B, and the clustering analyses of these genes resulted in 9 clusters. Three clusters among the 9 showed down-regulation by SH21B (cluster 4, cluster 6 and cluster 9), and two clusters showed up-regulation by SH21B (cluster 7 and cluster 8) during the adipogenesis of 3T3-L1 cells. It was found that many genes related to cell proliferation and adipogenesis were included in these clusters. Clusters 4, 6 and 9 included genes which were related with adipogenesis induction and cell cycle arrest. Clusters 7 and 8 included genes related to cell proliferation as well as adipogenesis inhibition. These results suggest that the mechanisms of the anti-adipogenic effects of SH21B may be the modulation of genes involved in cell proliferation and adipogenesis.

In our previous study, it was reported that an herbal mixture, SH21B, inhibits fat accumulation and adipogenesis both in vitro and in vivo models of obesity. SH21B is a mixture composed of seven herbs: Scutellaria baicalensis Georgi, Prunus armeniaca Maxim, Ephedra sinica Stapf, Acorus gramineus Soland, Typha orientalis Presl, Polygala tenuifolia Willd, and Nelumbo nucifera Gaertner (Ratio 3:3:3:3:3:2:2). The aim of this study was to investigate the detailed molecular mechanisms of the effects of SH21B on various regulators of the adipogenesis pathway. During the adipogenesis of 3T3-L1 cells, SH21B significantly decreased the expression levels of central transcription factors of adipogenesis, such as peroxisome proliferator-activated receptor (PPAR)γ and CCAAT/enhancer binding protein (C/EBP)α. To elucidate the detailed molecular mechanism of the anti-adipogenic effects of SH21B, we examined the expression levels of the various pro-adipogenic or anti-adipogenic regulators of adipogenesis upstream of PPARγ and C/EBPα. The mRNA levels of Krox20 and Kruppel-like factor (KLF) 15, which are pro-adipogenic regulators, were significantly down-regulated by SH21B treatment, whereas the mRNA levels of C/EBPβ and KLF5 were not changed. KLF2 and C/EBP homologous protein (CHOP), which are anti-adipogenic regulators, were significantly up-regulated by SH21B treatment. These results suggest that the molecular mechanism of the anti-adipogenic effect of SH21B involves both the down-regulations of pro-adipogenic regulators, such as Krox20 and KLF15, and the up-regulations of anti-adipogenic regulators, such as KLF2 and CHOP, which results in the suppression of central transcription factors of adipogenesis including PPARγ and C/EBPα.