• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1238-1244
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• 2004

The suppressive effects of Platycodi Radix (Changkil: CK), the root of Platycodon grandiflorum A. DC (Campanulaceae), on the progress of acute carbon tetrachloride $(CCl_4)$-induced hepatic fibrosis were investigated in the rat. CK significantly suppressed $(CCl_4)$-induced hepatic necrosis and inflammation, as determined by the serum enzymatic activities of alanine and aspartate aminotransferase and serum tumor necrosis factor-${\alpha}$ levels, in dose-dependent manners. In addition, the increased hepatic fibrosis after acute $(CCl_4)$ treatment was suppressed by the administration of CK. CK also significantly prevented the elevation of hepatic ${\alpha}$ 1(I) procollagen (type I collagen) mRNA and ${\alpha}$ -smooth muscle actin (${\alpha}$ -SMA) expressions in the liver of $(CCl_4)$-intoxicated rats and also suppressed the induction of ${\alpha}$ -SMA and type I collagen in cultured hepatic stellate cells, in dose-dependent manners. These results suggest that the suppressive effects of CK against the progress of acute $(CCl_4)$-induced hepatic fibrosis possibly involve mechanisms related to its ability to block both hepatic inflammation and the activation of hepatic stellate cells.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.4
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• pp.453-461
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• 2019

In this paper, we focus on the study of multi-node rendezvous on one common channel among multiple channels before transmitting in CRAHNs (Cognitive Radio Ad-hoc Networks) for the efficient use of inefficient frequency resources. Most existing researches have dealt with the channel rendezvous between two nodes. But, it can be time-consuming to apply them to three or more nodes. In addition, it cab be impossible to communicate with each other. Therefore, in this paper, we propose a Multi-Node Sequence (MNSEQ), which allows three or more nodes to rendezvous on a single common channel in a short period of time. And, CSMA/CA was applied for data exchange after rendezvous. By performance evaluation through very extensive simulations, we have demonstrated that the proposed MNSEQ outperforms the existing scheme in terms of communication completion time and transmission efficiency.