Papers by Keyword: BMP

Abstract: In the prediction and improvement of integrated circuit yield, it needs to convert CIF file to BMP file in order to calculate the critical area accurately and optimize the subsequent layout, at the same time, the image format of layout is the foundation of random defects hot spot detection. Firstly, the structures of CIF file and BMP file are studied, and various commands of CIF are deeply analyzed. Secondly, we design the algorithm that is based on the primitives are converted into BMP according to the representation of four basic primitives (rectangle, polygon, circularity, line with width) in CIF layout. Finally, we realize the algorithm of the whole CIF files is converted into BMP files. It is simple, conversion accuracy is high, more importantly, laid the foundation for the improvement of integrated circuit yield, and use C++ language to realize the CIF files conversion software based on the algorithm.

Abstract: The purpose of the present study was to observe the response and changes of cranial suture to the distraction forces in growing goats and to examine the expression patterns of TGF-β and BMP during suture distraction.Twenty growing goats were divided into three groups: control (n=4), experimental (n=12), and sham (n=4). A pure titanium distractor was placed in the coronal suture in both the sham and experimental groups. After healing, the distractor was activated for distraction of the coronal suture at a rate of 0.5 mm/day for 8 days in the experimental group. Three animals were killed respectively, at 0，2，4 and 8 weeks after completion of suture distraction. No force was applied in the sham group. X- Ray examination was taken and the coronal suture samples were harvested and processed for histological analysis and scanning electron microscopic analysis and immunohistochemistry of TGF-β and BMP. The coronal sutures of experimental group were separated successfully. Signs of intramembranous bone formation and remodeling were found in the distracted suture，and the sutural structure almost return to its normal state at 8 weeks after end of distraction. At 0 and 2 weeks after completion of suture distraction, the collagen fiber bundles were strengthened and aligned in the direction of the distracted forces. Strong expression of BMP and TGF-β were detected in the fibroblast-like cells and the active osteoblasts. At 4 weeks after suture distraction, signs of intramembranous ossification were found in the edge areas of the distracted suture, and the positive staining of BMP and TGF-β was still noted in the osteoblasts around the newly formed bone trabeculae. This study suggests that cranial suture expansion can be achieved in growing animal by distraction osteogenesis. Mechanical strain resulted from distractor can induce the adaptive remodeling in the cranial suture of growing goats. It also suggests BMP and TGF-β may play very important roles in the process of bone formation and remodeling during suture distraction osteogenesis.

Abstract: Bone morphogenetic protein (BMP) is known as a protein that induces new bone in heterotopic sites. This study was conducted to assess the cell-biological effects of crude porcine BMP and 3 pulp-capping materials by implantation and cell culture methods. The following results were obtained: a new bone site of approx 5mm in diameter were induced in the hind limbs, which confirmed the osteoinductive activity of the crude BMP. The pulp-capping materials hardly influenced the calcification of rat dental pulp (RDP) cells. Our data also suggest that the effect of the crude BMP on the proliferation and calcification depended on its quantity. The finding of a large increase in the ALPase activity and the formation of mineralized nodules caused by the crude BMP , suggests that the crude BMP enhanced the calcification by RDP cells. Consequently, it is quite possible that crude porcine BMP could be used as a pulp-capping material.

Abstract: Collagen-HA scaffolds were prepared by a phase-separation technique, cross-linked by formaldehyde or carbodiimide(EDC)/N-hydroxysuccinimide(NHS), which is also used to covalently attach chondroitin sulfate(CS) to the scaffold. BMP was incorporated into the scaffold by adsorption. The scaffolds were characterized by SEM and ESCA. Rat mesenchymal stem cell(MSCs) was seeded into the scaffold and cultured to form a cell/scaffold construct. The ectopic osteoinduction of the scaffolds were evaluated in vivo. The results show that the scaffolds are porous with three-dimensionality, have good cell compatibility and osteoinduction. Attachment of CS can improve the adhesion and differentiation of cells.

Abstract: It is well known that bone morphogenetic protein (BMP) induces bone formation and requires for carriers. Poly-lactic acid / poly-glycolic acid (PLGA) is frequently used as the carriers of BMP. We developed a biodegradable composite PLGA membrane, which was containing oriented needle-like apatite with BMP. The composite membranes were implanted into the thigh muscle pouch of 3-week-old-mice. At 3 weeks after implantation, the implanted area was observed by optical microscopy. The composite membrane containing oriented needle-like apatite with BMP induced new bone formation. It seems that this composite membrane might be a scaffold of BMP and promoting the healing of bone defects.