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41.
Novel trisaccharide fatty acid ester identified from the fruits of Morinda citrifolia (Noni) 总被引:4,自引:0,他引:4
Wang M Kikuzaki H Csiszar K Boyd CD Maunakea A Fong SF Ghai G Rosen RT Nakatani N Ho CT 《Journal of agricultural and food chemistry》1999,47(12):4880-4882
Two known glycosides and a novel trisaccharide fatty acid ester were isolated from the n-butanol-soluble fraction of the fruits of Morinda citrifolia (noni). Structure determination was carried out by spectral techniques such as MS, IR, NMR, and 2D-NMR. The novel trisaccharide fatty acid ester was elucidated as 2, 6-di-O-(beta-D-glucopyranosyl)-1-O-octanoyl-beta-D-glucopyranose. The known compounds were identified as rutin and asperulosidic acid. 相似文献
42.
Rafi MM Vastano BC Zhu N Ho CT Ghai G Rosen RT Gallo MA DiPaola RS 《Journal of agricultural and food chemistry》2002,50(4):677-684
Herbal therapies are commonly used by patients with cancer, despite little understanding about biologically active chemical derivatives. We recently demonstrated that the herbal combination PC-SPES, which contains licorice root, had anti-prostate cancer activity attributable to estrogen(s) that produced a chemical castration. A recent study also demonstrated that licorice root alone decreased circulating testosterone in men. Other studies demonstrated antitumor activity of PC-SPES in vitro associated with decreased expression of the anti-apoptotic protein Bcl-2 and in patients independent of chemical castration, suggesting that other mechanisms of antitumor activity exist separate from chemical castration. In the present study, we assessed licorice root extract for effects on Bcl-2 to identify novel cytotoxic derivatives. Licorice root extract induced Bcl-2 phosphorylation as demonstrated by immunoblot and G2/M cell cycle arrest, similarly to clinically used antimicrotubule agents such as paclitaxel. Bioassay-directed fractionations resulted in a biologically active fraction for Bcl-2 phosphorylation. HPLC separation followed by mass spectrometry and NMR identified 6 compounds. Only one molecule was responsible for Bcl-2 phosphorylation; it was identified as 1-(2,4-dihydroxyphenyl)-3-hydroxy-3-(4'-hydroxyphenyl) 1-propanone (beta-hydroxy-DHP). The effect on Bcl-2 was structure specific, because alpha-hydroxy-DHP, 1-(2,4-dihydroxyphenyl)-2-hydroxy-3-(4'-hydroxyphenyl) 1-propanone, in contrast to beta-hydroxy-DHP, was not capable of Bcl-2 phosphorylation. Pure beta-hydroxy-DHP induced Bcl-2 phosphorylation in breast and prostate tumor cells, G2/M cell cycle arrest, apoptosis demonstrated by Annexin V and TUNEL assay, decreased cell viability demonstrated by a tetrazolium (MTT) assay, and altered microtubule structure. Therefore, these data demonstrate that licorice root contains beta-hydroxy-DHP, which induced Bcl-2 phosphorylation, apoptosis, and G2/M cell cycle arrest, in breast and prostate tumor cells, similarly to the action of more complex (MW >800) antimicrotubule agents used clinically. 相似文献
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Sang S Kikuzaki H Lapsley K Rosen RT Nakatani N Ho CT 《Journal of agricultural and food chemistry》2002,50(16):4709-4712
One sphingolipid, 1-O-beta-D-glucopyranosyl-(2S,3R,4E,8Z)-2-[(2R)-2-hydroxyhexadecanoylamino]-4,8-octadecadiene-1,3-diol, and four other constituents, beta-sitosterol, daucosterol, uridine, and adenosine, have been isolated from the nuts of almond (Prunus amygdalus). Complete assignments of the proton and carbon chemical shifts for the sphingolipid were accomplished on the basis of high-resolution 1D and 2D NMR data. All of these compounds are being reported from almond nuts (P. amygdalus)for the first time. 相似文献
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G. D. Rosen 《Veterinary research communications》1983,7(1):73-81
The nutritional efficacy of antibacterial feed additives in improving animal performance and reducing production costs has been studied extensively for over thirty years. Responses vary greatly with time and place and quantitative estimates thereof are required, with appropriate confidence limits for different circumstances, to assist efficient practical application of such performance promoters in animal production. Modern computers have facilitated multi-factorial analysis of dose-response relationships and the elucidation of the influence of diverse other determinants, such as level of animal performance and duration of supplementation. The objectives, underlying principles, methodology and future prospects of comprehensive assessments, in the format of algebraic models, are reviewed and are illustrated by examples drawn from the use of copper, tylosin and bacitracin in the nutrition of pigs, broilers and laying hens. 相似文献
46.
LM Antunes MSc DVM JV Roughan BSc PhD & PA Flecknell MA Vet MB PhD DLAS Dip ECVA 《Veterinary anaesthesia and analgesia》2001,28(4):196-203
Objectives To assess a method for monitoring depth of anaesthesia using components of middle latency auditory evoked potential (AEP) waveforms during anaesthesia with fentanyl/fluanisone and midazolam. Study design Prospective observational study. Animals Five female Wistar rats weighing between 210 and 250 g. Methods Implanted electrodes were used to record AEPs in animals receiving five doses of anaesthetic. Recordings were made at 5 minutes post‐injection (deep anaesthesia; no pedal withdrawal response, PWR) and then at 25 minutes (light anaesthesia; strong PWR). Responses showed five characteristic peaks occurring at 11, 14, 23, 42 and 68 ms that were measured for latency of occurrence and peak amplitude. Results Auditory evoked potential peaks P14, N23 and P42 were increased significantly in latency with successive anaesthetic injections [avg. F(1,4) = 12.53, p < 0.001; avg. F(1,4) = 10.6, p < 0.001; avg. F(1,4) = 3.9, p = 0.02, respectively]. Peak N23 showed a significant reduction in latency during the 20 minute recovery period following both the first and second anaesthetic injections (t(3) = 7.52, p = 0.005; t(4) = 5.17, p = 0.007, respectively). Peak P42 occurred significantly earlier 20 minutes following the second anaesthetic injection (t(4) = 4.75, p = 0.009). The mean overall depth of anaesthesia assessed using PWR scores was significantly correlated with the mean latency of peak N23, such that as the strength of PWR increased, N23 occurred significantly earlier (r = ?0.99, p = 0.01). The amplitude difference between peaks N23 and P42 increased after the second and third drug administrations [avg. F(1,4) = 10.65, p = 0.031 and avg. F(1,4) = 11.24, p = 0.028, respectively]. Conclusion The characteristics of these peaks, and in particular latency of peak N23, may provide a useful tool for assessing depth of anaesthesia produced by this, and possibly other anaesthetic agents. 相似文献
47.
Rosen H. v. 《Journal of pest science》1961,34(4):62
Ohne Zusammenfassung 相似文献
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I Yeruham A Hadani F Galker S Rosen 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1989,42(2):233-235
The seasonal distribution of the tick Rhipicephalus bursa in sheep has been studied during one year in two neighbouring flocks of Awassi sheep in an enzootic focus of sheep babesiosis. Rates of tick infestation on the two flocks were very different. Pre-imaginal stages were found on the sheep during the winter months of November-March while adult ticks appeared in the middle of April and persisted until the end of July. First clinical cases of babesiosis in sheep were diagnosed 2 weeks after finding the first adult ticks. The pre-imaginal stages were found mainly in the pinnas while adult ticks preferred in decreasing order the tail, body and head. Few adult ticks were found on the legs. 相似文献