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101.
Maryam Jamil Ihsan ul Haq Bushra Mirza Mazhar Qayyum 《Annals of clinical microbiology and antimicrobials》2012,11(1):1-11
Background
Four medicinal plants (Chrozophora hierosolymitana Spreng, Chrysanthemum leucanthemum L., Ephedra gerardiana Wall. ex Stapf, and Quercus dilatata L.) used by indigenous healers to treat various infectious diseases were selected for the present study. The major objective of the present study was isolation and characterization of antimicrobial components from the crude plant extracts using bioassay guided fractionation.Methods
Seven methanolic extracts of the four plants were screened to identify any antimicrobial agents present in them. The active crude plant extract was fractionated first by solvent partitioning and then by HPLC. Characterization of the active fractions was done by using spectrophotometer.Results
All the seven methanolic extracts showed low antifungal activity, however, when these extracts were tested for antibacterial activity, significant activity was exhibited by two extracts. The extract of aerial parts of Q. dilatata was most active and therefore, was selected for further analysis. Initially fractionation was done by solvent-solvent partitioning and out of six partitioned fractions, ethanol fraction was selected on the basis of results of antibacterial activity and phytochemical analysis. Further, fractionation was carried out by RP- HPLC and purified active subfractions were characterized by comparing their absorption spectra with that of the known natural products isolated from the plants of Quercus genus.Discussion and conclusion
The results suggest that this is the first report of the isolated antibacterial compounds from this genus. 相似文献102.
In the present study, although some evidence in favour of a circadian variation in brain spermidine concentration was obtained in Swiss mice, peak concentrations occurred during darkness and were therefore out of phase with those reported in a previous study in the same mouse strain (Rodichok and Friedman, 1978). In addition the largest magnitudes of oscillation (34.8 and 22.7% for spermidine and spermine, respectively) were only about one quarter as large as those previously reported. The changes in polyamines did not correlate with change in locomotor activity. In C.D. mice a more complex pattern of change in spermidine was observed with peaks occurring in both the light and the dark phases of the cycle. Exposure of these animals to continuous light or continuous darkness modified the pattern of these fluctuations but did not abolish them.
It is concluded that, although daily fluctuations in spermidine and spermine concentration do occur in both entrained and free running mice such changes do not correlate with the phase of the light-dark cycle or with locomotor activity. 相似文献
103.
The Hengduan Mountains region of south-west China is a noted biodiversity,hotspot, but the geographic origins and historical assembly of its rich endemic flora, including the sky-island species of Solms-laubachia Muschl. (Brassicaceae), have been little studied. Previous molecular studies on the phylogeny of Solms-laubachia showed it to be paraphyletic, leading to considerable expansion not only of its taxonomic limits, but also its geographic range, with the inclusion of taxa from outside the Hengduan region. However, these studies provided little resolution of interspecific relationships, preventing inferences about historical biogeography within the clade. In the present study, new sequence data from two nuclear genes (LEAFY and G3pdh) and two chloroplast intergenic spacers (petN-psbM and psbM-trnD) were combined with existing markers to increase phylogenetic signals. Phaeonychium villosum (Maxim.) Al-Shehbaz was found to be nested within Solms-laubachia s.l. In general, phylogenetic relationships appear to be a good predictor of geography, with the Hengduan Mountain endemics embedded in a paraphyletic grade of species from the western Himalayas and central Asia, but they also imply morphological homoplasy. Incongruence was detected between the nuclear and chloroplast gene trees, perhaps resulting from incomplete lineage sorting of ancestral polymorphisms. The crown age of Solms-laubachia s.l. was estimated to be approximately 1.42-3.68 mya, using Bayesian relaxed molecular clock analysis. Historical biogeographic analysis using a parametric dispersal-extinction-cladogenesis model inferred central Asia and the western Himalayas as most probable ancestral range of Solms-laubachia s.l., and estimated higher rates of eastward expansion than westward during the diversification of descendant lineages. In summary, our results suggest that Solms-laubachia s.l. originated during the Pliocene in central Asia, and subsequently migrated eastward into the Hengduan Mountains, colonizing sky-island, alpine scree-slope habitats that may have provided novel ecological opportunity and accelerated speciation, ultimately establishing this region as the present center of diversity of the genus. 相似文献
104.
105.
Ersöz T Alipieva KI Yalçin FN Akbay P Handjieva N Dönmez AA Popov S Caliş I 《Zeitschrift für Naturforschung. C, Journal of biosciences》2003,58(7-8):471-476
A new phenylethanoid tetraglycoside, physocalycoside (2), was isolated from the aerial parts of Phlomis physocalyx. Its structure was identified as 3-hydroxy-4-methoxy-beta-phenylethoxy-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1-->3)]-4-O-feruloyl-[beta-D-glucopyranosyl-(1-->6)]-beta-D-glucopyranoside, on the basis of spectroscopic evidence. In addition, one known iridoid glucoside, lamiide (1) and five known phenylethanoid glycosides, wiedemannioside C (3), verbascoside (= acteoside) (4), leucosceptoside A (5), martynoside (6), and forsythoside B (7) were also characterized. Compounds 2-7 demonstrated radical scavenging properties towards the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. 相似文献
106.
Weinfeld AB Cheng J Nath RK Basaran I Yuksel E Rose JE 《Plastic and reconstructive surgery》2002,110(3):774-779
Division of the superior transverse scapular ligament for decompression of suprascapular nerve entrapment can be curative. However, the superior transverse scapular ligament can be difficult to locate, and large incisions are often required. This study was designed to determine the topographic coordinates of the superior transverse scapular ligament to permit reproducible surgical localization and reduce incision size. In 20 cadavers, the superior transverse scapular ligament was identified through a superior approach. Measurements were obtained from the superior transverse scapular ligament to external landmarks. The superior transverse scapular ligament was located 1.3 +/- 0.3 cm (+/- SD) posterior to the posterior border of the clavicle and 2.9 +/- 0.8 cm from the acromioclavicular joint in a two-dimensional surface plane. The depth of the superior transverse scapular ligament from the skin surface was 3.9 +/- 0.7 cm. An incision (mean length, 6.3 +/- 0.7 cm) derived from a novel system of planning marks facilitated access to the superior transverse scapular ligament. The authors conclude that the superior transverse scapular ligament can be located consistently through an incision located on the superior aspect of the shoulder on the basis of palpable topographic landmarks. The superior approach permits small incision size and the maintenance of local muscle anatomic integrity. 相似文献
107.
New directions in computational methods for the prediction of protein function are discussed. THEMATICS, a method for the location and characterization of the active sites of enzymes, is featured. THEMATICS, for Theoretical Microscopic Titration Curves, is based on well-established finite-difference Poisson-Boltzmann methods for computing the electric field function of a protein. THEMATICS requires only the structure of the subject protein and thus may be applied to proteins that bear no similarity in structure or sequence to any previously characterized protein. The unique features of catalytic sites in proteins are discussed. Discussion of the chemical basis for the predictive powers of THEMATICS is featured in this paper. Some results are given for three illustrative examples: HIV-1 protease, human apurinic/apyrimidinic endonuclease, and human adenosine kinase. 相似文献
108.
Slantchev K Yalçin F Ersöz T Nechev J Caliş I Stefanov K Popov S 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(5-6):534-540
Sterols, volatiles and lipids were isolated and identified from lipophylic extracts from two tunicates, Styela sp. and Phallusia sp., occurring in the Eastern Mediterranean. Seventeen sterols were identified. The sterol composition of the two organisms appeared to be similar except for the concentrations of 5alpha-stanols. Both tunicates were characterized by the presence of sterols with a (22Z)-double bond. In the volatiles significant amounts of chlorinated compounds were found (phenols in Styela sp. and hydrocarbons in Phallusia sp.). The fatty acid composition of triacylglycerols and phospholipids of the two tunicates showed significant differences. 相似文献
109.
Ihsan Serhatlioglu Batuhan Bilgin Emine Kacar Sibel Ozcan Sinan Canpolat Ahmet Ayar Haluk Kelestimur Mete Ozcan 《Journal of cellular physiology》2019,234(7):10741-10746
Agomelatine, a novel antidepressant exerting its effects through melatonergic and serotonergic systems, implicated to be effective against pain including neuropathic pain but without any knowledge of mechanism of action. To explore the possible role of agomelatine on nociceptive transmission at the peripheral level, the effects of agomelatine on intracellular calcium ([Ca2+]i) signaling in peripheral neurons were investigated in cultured rat dorsal root ganglion (DRG) neurons. Using the fura-2-based calcium imaging technique, the effects of agomelatine on [Ca2+]i and roles of the second messenger-mediated pathways were assessed. Agomelatine caused [Ca2+]i signaling in a dose-dependent manner when tested at 10 and 100 μM concentration. Luzindole, a selective melatonin receptor antagonist, almost completely blocked the agomelatine-induced calcium signals. The agomelatine-induced calcium transients were also nearly abolished following pretreatment with the 100 ng/ml pertussis toxin, a Gi/o protein inhibitor. The stimulatory effects of agomelatine on [Ca2+]i transients were significantly reduced by applications of phospholipase C (PLC) and protein kinase C (PKC) blockers, 10 μM U73122, and 10 μM chelerythrine chloride, respectively. The obtained results of agomelatine-induced [Ca2+]i signals indicates that peripheral mechanisms are involved in analgesic effects of agomelatine. These mechanisms seems to involve G-protein-coupled receptor activation and PLC and PKC mediated mechanisms. 相似文献
110.
Berkan O Bagcivan I Kaya T Yildirim K Yildirim S Doğan K 《Canadian journal of physiology and pharmacology》2007,85(5):521-526
The radial artery (RA) is used as a spastic coronary bypass graft. This study was designed to investigate the mechanism of vasorelaxant effects of YC-1 (3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole), a nitric oxide (NO)-independent soluble guanylate cyclase (sGC) activator, and DEA/NO (diethylamine/nitric oxide), a NO-nucleophile adduct, on the human RA. RA segments (n = 25) were obtained from coronary artery bypass grafting patients and were divided into 3-4 mm vascular rings.Using the isolated tissue bath technique, the endothelium-independent vasodilatation function was tested in vitro by the addition of cumulative concentrations of YC-1 (10-10 to 3 x 10-7 mol/L) and DEA/NO (10-8 to 3 x 10-5 mol/L) following vasocontraction by phenylephrine in the presence or absence of 10-5 mol/L ODQ (1H-(1,2,4)oxadiazole(4,3-a)quinoxalin-1-one), the selective sGC inhibitor, 10-7 mol/L iberiotoxin, a blocker of Ca2+-activated K+ channels, or 10-5 mol/L ODQ plus 10-7 mol/L iberiotoxin. We also evaluated the effect of YC-1 and DEA/NO on the cGMP levels in vascular rings obtained from human radial artery (n = 6 for each drug). YC-1 (10-10 to 3 x 10-7 mol/L) and DEA/NO (10-8 to 3 x 10-5 mol/L) caused the concentration-dependent vasorelaxation in RA rings precontracted with phenylephrine (10-5 mol/L) (n = 20 for each drug). Pre-incubation of RA rings with ODQ, iberiotoxin, or ODQ plus iberiotoxin significantly inhibited the vasorelaxant effect of YC-1, but the inhibitor effect of ODQ plus iberiotoxin was significantly more than that of ODQ and iberiotoxin alone (p < 0.05). The vasorelaxant effect of DEA/NO almost completely abolished in the presence of ODQ and iberiotoxin plus ODQ, but did not significantly change in the presence of iberiotoxin alone (p > 0.05). The pEC50 value of DEA/NO was significantly lower than those for YC-1 (p < 0.01), with no change Emax values in RA rings. In addition, YC-1-stimulated RA rings showed more elevation in cGMP than that of DEA/NO (p < 0.05). These findings indicate that YC-1 is a more potent relaxant than DEA/NO in the human RA. The relaxant effects of YC-1 could be due to the stimulation of the sGC and Ca2+-sensitive K+channels, whereas the relaxant effects of DEA/NO could be completely due to the stimulation of the sGC. YC-1 and DEA/NO may be effective as vasodilator for the short-term treatment of perioperative spasm of coronary bypass grafts. 相似文献