OBJECTIVE Betacellulin (BTC), purified and cloned from mouse beta cell tumor (BTC-JC10), is regarded as a new member of the epidermal growth factor family. The present study was conducted to clarify the expression of BTC and its receptors, ErbB-1 and ErbB-4, in the trophoblasts in the human placenta over the course of pregnancy. DESIGN AND METHODS Human placental tissues were obtained from 4 ...

Betacellulin (BTC), a ligand of the epidermal growth factor receptor, has been shown to promote growth and differentiation of pancreatic β-cells and to improve glucose metabolism in experimental diabetic rodent models. Mesenchymal stem cells (MSCs) have been already proved to be multipotent. Recent work has attributed to rat and human MSCs the potential to differentiate into insulin-secreting c...

Activation of EGF receptors is closely involved in vascular proliferative diseases. The signaling mechanisms of EGF ligands, including betacellulin (BTC) and amphiregulin (AR), are poorly understood. We examined how BTC and AR induced DNA synthesis activity in primary cultures of human thoracic aortic smooth muscle cells (HTASMCs). BTC induced phosphorylation of all four EGF receptors present o...

Block Truncation Coding (BTC), using a one-bit moment preserving quantizer to quantize a block, is a simple compression method; however, compression with BTC cannot be used to obtain a sufficiently high quality image, especially an image with many edges. In this paper, a new generalized multilevel BTC algorithm, which arbitrarily specifies the number of quantization levels, is developed. In the...

We introduce a simple image coding method, the block truncation coding (BTC) technique, as a novel approach to the construction of colour image databases. It is shown that BTC can not only be used to compress the images thus achieving storage eflciency. the BTC codes can also be used directly to construct image features for effective image retrieval. From the BTC code we have developed an image...

In this paper, Block Turbo Codes (BTC), that is product codes obtained from the concatenation of either two extended or two expurgated BCH codes are evaluated for the HIPERLAN/2 system. Simulations show that only expurgated BTC outperforms the performance of the Convolutional Code (CC) specified in the standard. This result is surprising since expurgated and extended BTC have same performance o...

Betacellulin (BTC) induces differentiation of pancreatic beta-cells and promotes regeneration of beta-cells in experimental diabetes. The present study was conducted to determine if BTC improved glucose metabolism in severe diabetes induced by a high dose of streptozotocin (STZ) in mice. Male ICR mice were injected with 200 microg/g ip STZ, and various doses of BTC were administered daily for 1...

BACKGROUND Betacellulin (BTC), a member of the epidermal growth factor family, is known to play an important role in regulating growth and differentiation of pancreatic beta cells. Growth-promoting actions of BTC are mediated by epidermal growth factor receptors (ErbBs), namely ErbB-1, ErbB-2, ErbB-3 and ErbB-4; however, the exact mechanism for beta cell proliferation has not been elucidated. T...

In this paper, a novel Gray Scale image compression method (BTC algorithm using Pattern fitting) based on block truncation coding (BTC) and Vector quantization (VQ) is proposed. This method inherits the advantages of both BTC and vector quantization. The BTC-PF method has some controlling parameters through which we can control the bit-rate and quality. The BTC-PF method is also successfully em...

Epidermal growth factor receptor (EGFR) is important for the proliferation and differentiation of gastric mucosal cells. Betacellulin (BTC) is a novel ligand for EGFR Since their role is unclear in the ulcer healing process, we investigated their expression. Gastric ulcers in 30 Sprague-Dawley rats were induced by acetic acid. RT-PCR and Western blotting were performed to detect EGFR and BTC. I...