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11.
Francesca Borrelli Nicola Borbone Raffaele Capasso Domenico Montesano Simona De Marino Gabriella Aviello Giovanni Aprea Stefania Masone Angelo A. Izzo 《Journal of ethnopharmacology》2009
Ethnopharmacological importance
Celastrus paniculatus Willd. (Celastraceae) is an Ayurvedic remedy used for the treatment of a number of diseases, including bowel spasms.Aim of the study
To investigate the mode of the relaxing action of a methanolic extract prepared from the seeds of Celastrus paniculatus (CPE, 0.0001–10 μg/mL) in the rat ileum and to try to confirm on human tissues the intestinal pharmacological activity of the extract.Materials and methods
The relaxant effect of CPE was studied in vitro by evaluating its effect on the spontaneous contractions of the isolated ileum.Results
CPE exerted a tetrodotoxin- and ω-conotoxin-resistant inhibitory effect on rat ileum motility (IC50: 0.24 ± 0.02 μg/mL; Emax: 99.0 ± 0.60%). The inhibitory effect was reduced by nifedipine but not by cyclopiazonic acid. Experiments with specific antagonists enabled us to exclude the involvement of the main endogenous spasmogenic (i.e. acetylcholine and tachykinins) and relaxing (noradrenaline, nitric oxide, ATP) compounds. CPE also relaxed the isolated human ileum (IC50: 0.26 ± 0.02 μg/mL; Emax: 99.1 ± 0.46%).Conclusion
It is concluded that (i) CPE exerted a powerful myogenic and L-type Ca2+-dependent relaxing effect in the isolated rat ileum and that (ii) the human ileum is sensitive to the inhibitory effect of CPE. If confirmed in vivo, our data could explain the traditional use of this herb in the treatment of intestinal spasms. 相似文献12.
TSo联合IFN-γ鼻内免疫小鼠诱导的弓形虫IgA抗体特异性免疫应答 总被引:23,自引:5,他引:18
目的研究速殖子超声裂解物(TSo)和IFN-γ鼻内免疫小鼠经口感染弓形虫速殖子后,血清、小肠液和粪便IgA抗体分泌的动态变化。方法将6~7周龄BALB/c小鼠100只随机分为4组,每组25只,分别用10μl缓冲液PBS、20μgTSo、500UIFN-γ和20μgTSo 500UIFN-γ鼻内免疫小鼠。用RH株弓形虫速殖子4×104个/只灌胃攻击,分别于攻击后第7、10、13、16、19天处死小鼠,收集血清、小肠液及粪便,ELISA法测定IgA含量。结果各组血清IgA抗体水平在攻击后第10天达到峰值,TSo IFN-γ组血清IgA抗体含量高于其他各组。小肠液和粪便IgA抗体含量在攻击后第13天达到峰值,在实验期各时点TSo IFN-γ组小肠液和粪便IgA抗体含量高于其他组。小肠液与粪便IgA抗体水平呈正相关。结论TSo或IFN-γ或TSo联合IFN-γ鼻内免疫小鼠可诱导黏膜免疫,产生高水平的弓形虫特异性IgA抗体。TSo联合IFN-γ鼻内免疫优于单独免疫,免疫小鼠肠道产生大量SIgA,发挥抗虫作用。鼻黏膜免疫是一种安全有效的免疫接种途径。 相似文献
13.
Akira Ishih Toshio Miyase Tohru Suzuki Francis W. Muregi Mamoru Terada 《Journal of natural medicines》2007,61(2):213-216
Febrifugine and isofebrifugine alkaloid mixtures extracted from the leaves and buds of Hydrangea macrophylla var. Otaksa, collected during different months, in Japan, were quantified using high-performance liquid chromatography. Leaves collected
during the flowering season, namely from June to August, contained 0.16–0.31 mg/g of the alkaloid mixture, whereas those collected
from September to December had less than 0.03 mg/g of the mixture. However, extracts of buds harvested from October to February
contained a consistently larger amount (more than 0.49 mg/g) of the alkaloids. Hot-water extracts from the leaves and buds
collected during different seasons were evaluated for antimalarial activity against Plasmodium yoelii 17XL in mice. The extract of leaves collected in August demonstrated high antimalarial activity, and all mice that received
the extract survived the infection. In contrast, the extract of leaves collected in December showed little activity. The extract
of buds collected in December cleared parasites, but with subsequent mortality to mouse. The present results show that the
amount of antimalarial agent—febrifugine and isofebrifugine mixture—in H. macrophylla var. Otaksa is both part- and season-dependent, suggesting that the choice of plant parts and their harvesting season are important factors
worth considering in the pharmacological use of medicinal plants. 相似文献
14.
Jocivania O da Silva Renata S Fernandes Fábio K Ticli Clayton Z Oliveira Maurício V Mazzi Jo?o J Franco Silvana Giuliatti Paulo S Pereira Andreimar M Soares Suely V Sampaio 《Toxicon》2007,50(2):283-291
We report here the antiproteolytic and antihemorrhagic properties of triterpenoid saponin inhibitors, named macrolobin-A and B, from Pentaclethra macroloba, against Bothrops snake venoms. The inhibitors were able to neutralize the hemorrhagic, fibrin(ogen)olytic, and proteolytic activities of class P-I and P-III metalloproteases isolated from B. neuwiedi and B. jararacussu venoms. Clotting and fibrinogenolytic activities induced by snake venoms and isolated thrombin-like enzymes were partially inhibited. Furthermore, the potential use of these inhibitors to complement antivenom therapy as an alternative treatment and/or used as molecular models for development of new therapeutical agents in the treatment of snake bite envenomations needs to be evaluated in future studies. 相似文献
15.
法半夏罗汉果川贝枇杷膏与强力枇杷露药理作用的比较研究 总被引:3,自引:0,他引:3
法半夏罗汉果川贝枇把膏与强力批他露均有镇咳祛痰作用,罗汉果川贝枇把膏尚能平喘抗炎。 相似文献
16.
在竹叶及其提取物中检出了相当含量的一种羟化赖氨酸—δ-OH-Lys,主要以游离单体和小肽的形式存在。从桂竹和金毛竹叶样分别测得其含量占干叶氨基酸总量的1.33%和1.40%,约相当于其中Lys含量的1/4.醇-水提取的过程有富集δ-OH-Lys的作用,其在提取物中的含量远远高于Lys.这一特殊的非蛋白氨基酸以相当含量存在于竹叶中,可能有着特殊的生物学意义。 相似文献
17.
目的:通过观察银杏叶提取物(EGb)对交感神经节细胞生物电的影响,为进一步探讨EGb调节肠系膜下神经节(IMG)支配的包括远端结肠在内的内脏功能活动的作用机制提供依据。方法:采用细胞内生物电记录技术记录体外IMG电位。结果:在敏感细胞,EGb761(35~350mg/L)可使71.0%的肠系膜下神经节细胞产生膜去极化反应,且在一定范围内呈现剂量效应关系;19.4%的细胞超极化;9.7%的细胞出现先超极化后去极化的双相反应。去极化反应的细胞其膜电阻有降低、增大和不变等多种表现。此去极化反应可被低钙.高镁克氏液部分阻断,但不为胆碱和肾上腺素受体阻断剂所阻断。还发现EGb761可抑制外源性5-HT引起的去极化电位。结论:EGb761对IMG细胞可能通过非胆碱能、非肾上腺素能通路产生易化作用;其机制可能与影响其他递质的释放有关。 相似文献
18.
19.
Ardawi MS Nasrat HA Rouzi AA Qari MH Al-Qahtani MH Abuzenadah AM 《BJOG : an international journal of obstetrics and gynaecology》2007,114(11):1397-1401
Objective To investigate the influence of cigarette or sheesha smoking on first-trimester markers of Down syndrome.
Design A prospective observational study.
Setting Primary care centres and antenatal clinics of Maternity and Children Hospital, King Abdulaziz University Hospital and New Jeddah Clinic Hospital, Jeddah, Saudi Arabia.
Population Women with a singleton pregnancy who were either nonsmokers ( n = 1736) or cigarette smokers ( n = 420) or sheesha smokers ( n = 181).
Methods Fetal nuchal translucency thickness (fetal NT), maternal serum free beta-human chorionic gonadotrophin (free β-hCG) and pregnancy-associated plasma protein-A (PAPP-A) were measured at 11 weeks 0 days to 13 weeks 6 days of gestation in all women. Women were grouped according to smoking status, confirmed by maternal serum cotinine measurements, and analyte levels between groups were compared.
Main outcome measures Fetal NT, maternal serum free β-hCG, PAPP-A and cotinine measurements.
Results Compared with nonsmoking women, fetal NT was significantly increased and free β-hCG and PAPP-A levels were significantly decreased in both cigarette and sheesha smokers. There were significant relationships between all three markers and the number of sheeshas consumed per day.
Conclusions Cigarette and sheesha smoking significantly affect first-trimester markers of Down syndrome (fetal NT, free β-hCG and PAPP-A). Correction for this effect in women who smoke might improve the effectiveness of first-trimester screening for Down syndrome in these women. The underlying mechanism(s) relating smoking to the changes in first-trimester markers require further studies. 相似文献
Design A prospective observational study.
Setting Primary care centres and antenatal clinics of Maternity and Children Hospital, King Abdulaziz University Hospital and New Jeddah Clinic Hospital, Jeddah, Saudi Arabia.
Population Women with a singleton pregnancy who were either nonsmokers ( n = 1736) or cigarette smokers ( n = 420) or sheesha smokers ( n = 181).
Methods Fetal nuchal translucency thickness (fetal NT), maternal serum free beta-human chorionic gonadotrophin (free β-hCG) and pregnancy-associated plasma protein-A (PAPP-A) were measured at 11 weeks 0 days to 13 weeks 6 days of gestation in all women. Women were grouped according to smoking status, confirmed by maternal serum cotinine measurements, and analyte levels between groups were compared.
Main outcome measures Fetal NT, maternal serum free β-hCG, PAPP-A and cotinine measurements.
Results Compared with nonsmoking women, fetal NT was significantly increased and free β-hCG and PAPP-A levels were significantly decreased in both cigarette and sheesha smokers. There were significant relationships between all three markers and the number of sheeshas consumed per day.
Conclusions Cigarette and sheesha smoking significantly affect first-trimester markers of Down syndrome (fetal NT, free β-hCG and PAPP-A). Correction for this effect in women who smoke might improve the effectiveness of first-trimester screening for Down syndrome in these women. The underlying mechanism(s) relating smoking to the changes in first-trimester markers require further studies. 相似文献
20.
目的探讨不同摄食控制方法对荷瘤小鼠生存期的影响。方法摄食控制组分别为每日限食2.0 g(DR)、隔1日断食限食4.0 g(IF)、隔2日断食限食6.0 g(SF)和隔1日断食不限食(IF1)4种方法,正常摄食为空白对照组(AL)。观察各组小鼠的体重变化和平均存活天数。结果DR组和IF组平均存活天数分别为19.52±5.24 d和17.96±4.49 d,比对照AL组15.75±1.83 d明显延长(P<0.001和P<0.01)。结论摄食控制恰当,可明显抑制肿瘤细胞的生长、延长荷瘤小鼠的生存期并提高生存质量。 相似文献