RESUMEN
The effectiveness of a ductile fracture model in accurately predicting fracture initiation has been demonstrated. In this study, we concentrate on applying the ductile fracture model to pre-cracked structures constructed from SUS304L stainless steel with experimental and numerical analyses. The Swift hardening law was employed to extend the plastic behavior beyond the onset of necking. Additionally, the Hosford-Coulomb model, integrated with a damaged framework, was utilized to predict ductile fracture behavior, particularly under non-proportional loading conditions. Tension tests were conducted on various specimens designed to illustrate various fracture modes resulting from geometric effects. Numerical analyses were conducted to explore the loading histories, utilizing an optimization process to calibrate fracture model parameters. The proposed fracture model is validated against pre-cracked structures detailed in a reference paper. The results convincingly demonstrate that the fracture model effectively predicts both fracture initiation and propagation in pre-cracked structures.
RESUMEN
Fibroblast growth factor 2 (FGF2) protein plays important roles in wound healing and tissue regeneration. Collagen is clinically used for wound care applications. We investigated the potential value of FGF2-functionalized collagen matrices for skeletal muscle tissue engineering. When C2C12 cells were treated with FGF2, cell adhesion increased after 3 and 5 days compared to the control (P < 0.05). Wound healing activity of FGF2 was slightly higher than the control through cell migration. Cell proliferation activity of FGF2-functionalized collagen matrices on C2C12 cells also increased. Taken together, FGF2 stimulated C2C12 myoblast growth by promoting cell adhesion, proliferation and wound healing activity after injury. The potential effect of FGF2-functionalized collagen matrices was also observed. Thus FGF2 stimulates skeletal muscle development and regeneration, thereby leading to potential utility for skeletal muscle tissue engineering.
Asunto(s)
Productos Biológicos/metabolismo , Colágeno/química , Portadores de Fármacos/química , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Sustancias de Crecimiento/metabolismo , Músculo Esquelético/efectos de los fármacos , Ingeniería de Tejidos/métodos , Animales , Productos Biológicos/química , Adhesión Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Factor 2 de Crecimiento de Fibroblastos/química , Sustancias de Crecimiento/química , Ratones , Mioblastos/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacosRESUMEN
Colorectal cancer is a common cancer and the fourth leading cause of death in Korea. The incidence and mortality of colorectal cancer varies according to risk factors, such as age, family history, genetic history, food habits, and physical activities. Some studies have focused on the association between vitamin D and colorectal cancer. Today, there is growing evidence that high vitamin D intake and a plasma level of 25(OH)D(3) reduce the incidence of colorectal cancer by modifying cancer angiogenesis, cell apoptosis, differentiation, and proliferation. Taken together, these results suggest that vitamin D supplementation alone, or in combination with anti-cancer agents, might reduce the incidence of colorectal cancer. In this review, we discuss the function and mechanism of vitamin D including the effect of vitamin D on colorectal cancer.
RESUMEN
The use of non-absorbable suture materials for cystic duct ligation after cholecystectomy can expose patients to the risk of recurrent stone formation in the common bile duct (CBD). However, in Korea suture materials have rarely been found to act as a nidus for common bile duct calculus formation. Recently, we experienced a case in which suture material, that had migrated from a previous cholecystectomy site into the CBD, probably served as a nidus for common bile duct stone formation. The stone was confirmed by endoscopic retrograde cholangiopancreatography (ERCP) and removed successfully using a basket. The authors report a case of surgical suture migration and discuss its subsequent role as a stone forming nucleus within the CBD in a patient who underwent open cholecystectomy; and include a review of the literature.