Various mechanical stimuli affect differentiation of mesoderm-derived cells such as osteoblasts or myoblasts, suggesting that adipogenesis may also be influenced by mechanical stimulation. However, effects of mechanical stimuli on adipogenesis are scarcely known. Compressive force was applied to a human preadipocyte cell line, SGBS. Levels of gene expression were estimated by real-time reverse transcription-polymerase chain reaction. The accumulation of lipids was evaluated by Sudan III or Oil Red O staining. In SGBS cells subjected to a compressive force of 226 Pa for 12 h before adipogenic induction, adipogenesis was inhibited. Compressive force immediately after adipogenic induction did not affect the adipogenesis. The expression of peroxisome proliferator-activated receptor (PPAR) gamma2 and CCAAT/enhancer binding protein (C/EBP) alpha mRNA during adipogenesis was inhibited by compressive force, whereas C/EBPbeta and C/EBPdelta mRNA levels were unaffected. In preadipocytes, compressive force increased mRNA levels of Krüppel-like factor 2, preadipocyte factor 1, WNT10b, and cyclooxygenase-2 (COX-2) which are known as negative regulators for the PPARgamma2 and C/EBPalpha genes. Furthermore, a COX-2 inhibitor completely reversed the inhibition of adipogenesis by compressive force. In conclusion, compressive force inhibited adipogenesis by suppressing expression of PPARgamma2 and C/EBPalpha in a COX-2-dependent manner.
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http://dx.doi.org/10.1016/j.jbiosc.2009.09.003 | DOI Listing |
Polymers (Basel)
January 2025
Department of Civil and Environmental Engineering, Ben-Gurion University of the Negev, Beer Sheva 8410501, Israel.
Rigid reinforced concrete (RC) frames are generally adopted as stiff elements to make the building structures resistant to seismic forces. However, a method has yet to be fully sought to provide earthquake resistance through optimizing beam and column performance in a rigid frame. Due to its high corrosion resistance, the integration of CFRP offers an opportunity to reduce frequent repairs and increase durability.
View Article and Find Full Text PDFPharmaceuticals (Basel)
December 2024
College of Pharmacy, Dankook University, 119, Dandae-ro, Dongnam-gu, Cheonan-si 31116, Republic of Korea.
: This study aimed to establish a predictive model for critical quality attributes (CQAs) related to tablet integrity, including tablet breaking force (TBF), friability, and capping occurrence, using machine learning-based models and nondestructive experimental data. : The machine learning-based models were trained on data to predict the CQAs of metformin HCl (MF)-containing tablets using a commercial-scale wet granulation process, and five models were each compared for regression and classification. We identified eight input variables associated with the process and material parameters that control the tableting outcome using feature importance analysis.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
School of Mechanical and Electrical Engineering, Guilin University of Electronic Technology, Guilin 541004, China.
Mechanoluminescent (ML) materials emit light by trapping and releasing charge carriers under mechanical stress. However, previous studies do not fully reveal the relationship between emitting light intensity and mechanical stress, thereby affecting the accuracy of stress measurement. This study addresses this gap by systematically investigating ML cylinders with various sizes and loading paths using theoretical analysis and simulations, focusing on the maximum contact stress, equivalent stress distribution, and the relationship between the strain energy density and light intensity at the point of maximum contact stress.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
School of Electrical & Control Engineering, Tongmyong University, Busan 48520, Republic of Korea.
Resilient mounts play a vital role in anti-vibration and shock-absorption systems, making precise estimation of their static and dynamic stiffness essential for ensuring optimal mechanical performance and effective design. This study investigates the behavior of resilient mounts by analyzing their static and dynamic stiffness characteristics through the application of various hyperelastic constitutive models. Seven hyperelastic models were reviewed and systematically compared using numerical simulations, experimental data, and analytical solutions.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
School of Civil and Architectural Engineering, Hunan Institute of Science and Technology, Yueyang 414000, China.
Ultra-high-performance concrete (UHPC) is a cement-based composite material characterised by exceptional strength, low porosity and high durability, making it highly promising for reinforcement engineering. Based on the theory of tangential modulus, a calculation method has been developed for the axial compression capacity of reinforced concrete (RC) medium and long columns strengthened with UHPC, using the constitutive relation of materials and internal and external force balance conditions. This study analysed the influence of UHPC reinforcement layer thickness, reinforced layer, reinforcement ratio, column slenderness ratio and initial load level of core columns on the bearing capacity of reinforced columns.
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