Gold salts and phenylbutazone selectively inhibit the synthesis of PGF2α and PGE2 respectively. Lowered production of one prostaglandin species is accompanied by an increased production of the other. Selective inhibition by these drugs was observed in the presence of adrenaline, reduced glutathione and copper sulphate under conditions when most anti-inflammatory compounds inhibited PGE2 and PGF2α syntheses equally. It is postulated that selective inhibitors may have a different mode of action
and beneficial effects may be related to the endogenous ratio of PGE to PGF required for normal function. 相似文献
Two secoiridoid glucosides, lucidumosides A and B, as well as six known glucosides, oleoside dimethyl ester, ligustroside, oleuropein, nuezhenide, isonuezhenide, and neonuezhenide, were isolated from the fruits of Ligustrum lucidum. Their structures were elucidated by spectroscopic methods. 相似文献
Using conserved plant sequences as primers, the DNA sequences in the ribosomal ITS1-5.8S-ITS2 region have been amplified and determined for six Panax species, P. ginseng C. A. Mey. (Oriental ginseng), P. quinquefolius L. (American ginseng), P. notoginseng (Burkill) F. H. Chen (Sanchi), P. japonicus C. A. Mey. (Japanese ginseng), P. trifolius L. and P. major Ting, as well as two common adulterants of ginseng, Mirabilis jalapa L. and Phytolacca acinosa Roxb. An authentication procedure based upon the restriction fragment length polymorphism (RFLP) in the region is able to differentiate between P. ginseng and P. quinquefolius, and to discriminate the ginsengs from the two common poisonous adulterants. Broader application of this approach to authenticate other morphologically similar Chinese medicinal materials is rationalised. 相似文献
A prenylated flavonoid, moralbanone, along with seven known compounds kuwanon S, mulberroside C, cyclomorusin, eudraflavone B hydroperoxide, oxydihydromorusin, leachianone G and alpha-acetyl-amyrin were isolated from the root bark of Morus alba L. Leachianone G showed potent antiviral activity (IC(50) = 1.6 microg/ml), whereas mulberroside C showed weak activity (IC(50) = 75.4 microg/ml) against herpes simplex type 1 virus (HSV-1). Their structures were elucidated by spectroscopic methods. 相似文献
Methanolic extract and two purified compounds (brazilin and hematoxylin) from Caesalpinia sappan were examined for their relaxant effects in isolated rat thoracic aorta. The methanolic extract significantly and dose-dependently relaxed the alpha1-receptor agonist phenylephrine-precontracted aortic rings, without affecting passive tension of these vessels. Removal of the vascular endothelium, inhibition of nitric oxide (NO) synthase with 0.1 mM Nomega-nitro-L-arginine and of cGMP biosynthesis with 10 microM methylene blue abolished the vasorelaxant effects of the herbal extract at doses up to 30 microg/ml. Similar vasorelaxant effects were observed with brazilin and hematoxylin. Therefore, these results suggest that brazilin and hematoxylin may be responsible for the vascular relaxant effects of C. sappan, via endogenous NO and subsequent cGMP formation. The vascular relaxant effects of the plant may contribute to its therapeutic actions. 相似文献
Tnt1 was the first active plant retrotransposon identified in tobacco after nitrate reductase gene disruption. The Tnt1 superfamily
comprises elements from Nicotiana (Tnt1 and Tto1) and Lycopersicon (Retrolyc1 and Tlc1) species. The study presented here was conducted to characterise Tnt1-related sequences in 20 wild species
of Solanum and five cultivars of Solanum tuberosum. 相似文献
Myzus persicae is a devastating pest affecting potato production. Intron-containing hairpin RNA (ihpRNA) silenced the odorant-binding protein 8 (OBP8) for enhanced protection against Myzus persicae in potatoes. OBP8 was isolated from M. persicae, sequenced, with the allotment of GenBank ID. ERNAi was used to design siRNA targets from OBP8 with no off-targets. Multiple Sequence Alignment show M. persicae OBP8 resemblance with Acyrthosiphon pisum, Rhopalosiphum maidis, Aphis fabae, and Sitobion avenae. dsRNA-OBP8 (7 µg/µL) oral feeding resulted in a 69% mortality, and 58% OBP8 reduced expression 8D post-feeding compared to control. Golden Gate cloning is used for RNA interference taking advantage of type IIs restriction enzyme Eco31I. ihpRNA-OBP8 introduced by agroinfiltration in Solanum tuberosum. Transgenic S. tuberosum fed Myzus show 57.6% mortality and 49% reduction in OBP8 expression 8D post-feeding, compared to control. This work proves OBP8 as promising ihpRNA targets in potato and related crops for whom Myzus is a destructive pest.