首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 109 毫秒
1.
Summary The prostaglandin-like substances (PLS) isolated fromP. acnes were investigated by reversed phase chromatography and gas chromatography-mass spectrometry. These analyses demonstrated that PLS were not identical with PGE2, which supports a concept of PLS as a potential mediator of the inflammatory process in acne vulgaris.  相似文献   

2.
Summary Three acidic polysaccharide (AP) fractions and the prostaglandin-like substances (PLS) isolated fromP. acnes were investigated regarding their chemotactic activities on polymorphonuclear leukocytes. Both AP's and PLS induced a significant chemotactic response, which suggests their involvement in inflammatory acne vulgaris.  相似文献   

3.
Summary The present study demonstrates a powerful vasoconstrictor activity of prostaglandin-like substances (PLS), extracted fromP. acnes, on human blood vessels. PLS is about equipotent to PGE2 in its effect on human umbilical vessels, but the contractile response pattern is different. PLS therefore seems to have specific and different physiological characteristics.  相似文献   

4.
Summary The activity spectrum of prostaglandin-like substances (PLS) fromP. acnes was investigated with cascade superfusion technique and by platelet aggregation assay. The biological activity of PLS resembles that of PGI2: both relax bovine coronary artery, rabbit mesentric and coeliac arteries; both contract the rat stomach strip as well as both typically inhibit spontaneous movements of isolated guinea pig ileum. Also, similarly to PGI2, PLS inhibits platelet aggregation regardless the inducer used. However, PLS possesses a specific antiaggregatory pattern on platelet, which indicates that these compounds are not indentical with primary prostaglandins or PGI2.  相似文献   

5.
The prostaglandin-like substances (PLS) from Propionibacterium acnes increased the ovarian tissue levels of cyclic AMP (cAMP) approximately 2-fold. The lipid material extracted from P. acnes thus behaved like PG's of the E-type, and since it is unlikely that other known stimulators of the ovarian cAMP system can be present in the bacterial lipid fraction, these experiments give further evidence in favour of the occurrence of PLS in P. acnes.  相似文献   

6.
Summary The lipid fraction ofP. acnes was submitted to stepwise purification followed by bioassay in order to localize the prostaglandin-like material. GC-MS analysis revealed the occurrence of substances having a part but not a total molecule in common with the prostaglandin family, suggesting that prostaglandin-like substances represent a new group of prostaglandin compounds.The competent technical assistance of Mr N. Engström and Mr G.A. de Vogel is gratefully acknowledged.  相似文献   

7.
Summary Exposure to glucose in the presence of 3-isobutyl-1-methylxanthine leads to accumulation of cAMP in islets microdissected fromob/ob-mice. This process is dependent on extracellular Ca++ but differs markedly from the glucose action on insulin release in the same in vitro system in disappearing after 18 h of starvation.Supported by the Swedish Medical Research Council (No. 12x562).  相似文献   

8.
Summary The lipid fraction, 17%, of air-driedPlexaura homomalla formakükenthali, collected in the Caribbean at Puerto Rico, yielded 50% of its weight as the mammalian prostaglandin (15S)-PGA2 methyl ester. The freeze-dried gorgonian yielded (15S)-PGA2 largely as the acetate of the methyl ester. (15S)-PGA2 was also obtained from material collected at St. Croix and at South Caicos. Field observations indicate thatPlexaura kükenthali may be a species separate fromPlexaura homomalla and that it is abundant on some shallow water reefs in the Caribbean. Prostaglandins could not be detected in the lipid fraction of eggs isolated fromPlexaura homomalla (Esper) formahomomalla.Acknowledgments. We gratefully acknowledge support from the Office of Sea Grant, NOAA, Department of Commerce (Grant 047-158-44067), and the use of facilities at the Isla Mayagues Marine Laboratory of the University of Puerto Rico, Mayaguez, the West Indies Laboratory of Fairleigh Dickinson University at St. Croix, U.S.V.I., and the Marine-Biologisch Instituut at Curacao. Special thanks to Dr. F.M. Bayer, Curator, Department of Zoology, National Museum of Natural History-Smithsonian Institution for checking identity of gorgonians used in this study.  相似文献   

9.
The biological activity of a lipid fraction extracted from P. acnes was tested on isolated smooth muscle strips from the human utero-tubal junction. The bioassay experiments support the concept that prostaglandin-like substances (PLS) occur in P. acnes. However, in the bioassay system used, the effect of PLS was different from that of PGF2 alpha and PGI2 but similar, although not identical, to that of arachidonic acid and PGE2.  相似文献   

10.
Summary For the isolation of chloroplasts in non-aqueous media the following organic solvents are suitable: pentane, hexane, heptane, petroleum ether and carbon tetrachloride. These solvents cause a minimum loss of lipids.The loss of lipids and some lipid components of frozendried and ground shoots fromElodea canadensis during the isolation of chloroplasts in non-aqueous media (petroleum ether b. r. 60–80°C and petroleum ether-carbon tetrachloride mixtures) is reported.  相似文献   

11.
Summary The presence of prostaglandin-like substances inPropionibacterium acnes is reported for the first time.  相似文献   

12.
A diterpenoid, totarol (1), fromPodocarpus nagi was evaluated as an antioxidant. This diterpenoid inhibited autoxidation of linoleic acid. Mitochondrial and microsomal lipid peroxidation induced by Fe(III)-ADP/NADH or Fe(III)-ADP/NADPH were also inhibited. Nagilactone E (2), a norditerpene lactone isolated from the same source, had no antioxidative activity. Furthermore, totarol protected red cells against oxidative hemolysis. This diterpene was shown to be effective in protecting biological systems against oxidative stresses.  相似文献   

13.
Summary Infestation of oilseed rape (Brassica napus L.) by the cabbage stem flea beetle (Psylliodes chrysocephala L.) leads to an overall reduction in the levels of aliphatic (alkenyl- and hydroxyalkenyl-) glucosinolates in the damaged tissue (lamina, petiole, stem) and a massive accumulation of indole glucosinolates. Whilst artificial damage (puncturing), with and without associated bacterial infection with an isolate fromP. chrysocephala, led to such accumulation, this was less than that observed in the insect-infected situation.  相似文献   

14.
Summary Physalis peruviana shrubs were not attacked by larvae ofSpodoptera littoralis. It was demonstrated that withanolide E, a steroid isolated fromP. peruviana, as well as several related steroids, have insect antifeedant properties.  相似文献   

15.
Summary The elimination of (14C)-DMN after i.p. injection intoXenopus was measured, as was the metabolism in vitro of (14C)-DMN by liver fromXenopus and 9 other amphibian species. In view of its rapid elimination from the body and low rate of metabolism byXenopus liver in vitro, DMN is unlikely to be toxic or carcinogenic inXenopus.This work was supported by a grant from the Cancer Research Campaign. We are also grateful to Dr P. F. Swann, both for the supply of DMN and DEN and for many useful discussions.  相似文献   

16.
Summary Concentrations of cyclic AMP (cAMP) were determined in paired fore and hind limbs from day 12–16 of development in murine fetuses homozygous for the brachymorphic (bm) mutation and normal controls. A developmental rise in cAMP occurred 1 day earlier inbm/bm than in +/+ hind limbs and cAMP was higher in day-13bm/bm than in +/+ fore limbs. Since cAMP is well documented to stimulate chondrogenic differentiation, premature cartilage determination secondary to altered levels of cAMP could play a role inbm/bm short-limbed dwarfism.This work was supported by a grant from the National Foundation-March of Dimes.  相似文献   

17.
(E)-3-tridecen-2-one, the major volatile component of interdigital gland extracts from the black-tailed deer,Odocoileus hemionus columbianus, inhibited the growth of gram-positive bacteria and fungi. The bacteria,Propionibacterium acnes, and the fungi,Trichophyton mentagrophytes had a minimum inhibitory concentration (MIC) of 12.5 g/mL and 25 g/mL, respectively.  相似文献   

18.
Gorgonian soft corals from the Caribbean Sea are known to contain prostaglandin-like compounds as well as other products of arachidonic acid lipoxygenation, and the formation of the latter has been suggested to represent the first step in prostaglandin biosynthesis. Here we present evidence for the presence of 11-R-hydroxy-5Z, 8Z, 12E, 14Z-eicosatetraenoic acid (11-R-HETE), as well as of the enzyme responsible for its biosynthesis, in the Caribbean gorgonianPlexaurella dichotoma. Lipid extracts fromP. dichotoma were purified by conventional SiO2 column chromatography followed by reversed phase high-pressure liquid chromatography (HPLC). These yielded a component having chromatographic and spectroscopic properties identical to synthetic 11-HETE. Electron impact mass spectrometric analysis of the acetoxy-, methyl ester derivative of the compound confirmed its identity as 11-HETE, while chiral phase HPLC of the methyl ester derivative showed that the stereochemistry of the alcoholic carbon atom wasR. Enzymatically active homogenates fromP. dichotoma were able to convert both unlabelled and [3H] arachidonic acid into 11-HETE. In vitro biosynthesis of the latter metabolite was also observed with homogenates of the Mediterranean gorgonianParamuricea clavata, another non-prostaglandin-containing soft coral, thus suggesting that 11-R-HETE production is not necessarily accompanied by prostaglandin formation in gorgonian corals.  相似文献   

19.
Summary Nosiheptide (9671 R.P.) isolated fromStreptomyces actuosus 40037 (NRRL 2954) is a sulfur-containing polypeptidic antibiotic, quite different from all the other members of this family. Very active in vitro against gram-positive bacteria, it is inactive in vivo in experimentally infected mice. Not toxic, even at high dose, it may be used as a feed additive for chickens and pigs and it shows a favourable effect on the growth and conversion index.  相似文献   

20.
Summary Precocene II (P II) was applied to the adult females of 2 Pyrrhocorid bugs —Pyrrhocoris apterus (insensitive to P II) andDysdercus cingulatus (sensitive to P II)-subjected to allatectomy and intraspecific or interspecific reimplantations of corpus allatum (CA). The failure of P II to inhibit ovarian development inP. apterus appears to be caused by both a low sensitivity to P II of the CA itself and unknown anti-precocene mechanisms outside the CA.Precocene II was kindly supplied by Zoecon.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号