Study of reason of "the older, the better" of Pericarpium Citri Reticulatae (PCR) which contributed increase of flavonoids / 中国中药杂志

This study is to explore the reason of "the older, the better" of PCR and itsincrease of flavonoids. We identified the fun- gus isolated from the PCR using microscopic and molecular identification. HPLC method was used to determine the content of 4 fla- vonoids and to clarifythe regularity of them; UV spectrophotometry method was used to determine the total content of flavonoids; reverse thinking was applied to screen the fungus that have close relation to the change of flavonoids. Finally, we have isolated and identified 25 fungusfrom the PCR, which belong to 2 genus and 4 species, including pencillium commune, P. minioluteeum, P. citrinum, Aspergillus flavus and A. niger. The content of flavonoids was increased in the mildew PCR due to A. niger and other fungus. Therefore, "the ol- der, the better" of PCR had its scientific reason that the increase of flavonoids had a close relation of the metabolic activity of A. niger and other fungus.

Effects of sodium hydrogen exchanger-1 hammerhead ribozyme on proliferation of pulmonary artery smooth muscle cells in rats in vitro / 中国应用生理学杂志

<p><b>AIM</b>To explore the effects of sodium hydrogen exchanger (NHE-1) specific hammerhead ribozyme on the expression and activity of NHE-1 and pHi in pulmonary artery smooth muscle cells (PASMCs) in rats, and its role in PASMCs proliferation.</p><p><b>METHODS</b>According to the secondary structure of NHE-1 mRNA in rats, NHE-1 specific hammerhead ribozyme was designed with the assistance of computer. The recombinant vector of retroviral plasmid pLXSN and NHE-1 hammerhead ribozyme, PRZ, was transfected into the cultured PASMCs. G418 resistant cell clones were screened with 60 microg/ml G418. Then, the expression of NHE-1 mRNA was detected by RT-PCR, intracellular pH was measured with fluorescent probe-BCECF, 22Na and 3H-TdR incorporation were determined respectively.</p><p><b>RESULTS</b>Compared with the cells transfected with pLXSN and non-transfected cells, NHE-1 mRNA, pHi value, 3H-TdR and 22Na incorporation decreased significantly in cells transfected with recombinant vector PRZ. No significance was found between the pLXSN transfected group and non-transfected group.</p><p><b>CONCLUSION</b>NHE-1 hammerhead ribozyme can cleave the target RNA specifically, reduce the expression of NHE-1 mRNA, induce intracellular acidosis and consequently prohibit the proliferation of PASMCs.</p>