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61.
62.
The antiproliferative constituents in the MeOH extracts of the aerial parts of Lippia dulcis Trev. and Lippia canescens Kunth (Verbenaceae) were investigated. Activity-guided chemical investigation of the MeOH extracts resulted in the isolation of the three bisabolane-type sesquiterpenes [(+)-hernandulcin (1), (-)-epihernandulcin (2), and (+)-anymol (3)] and four phenylethanoid glycosides [acteoside (4), isoacteoside (5), martynoside (6), and a new diacetylmartynoside (7)] from the former, and four phenylethanoid glycosides [acteoside (4), isoacteoside (5), arenarioside (8), and leucosceptoside A (9)] and three flavones [desmethoxycentaureidin (10), eupafolin (11), and 6-hydroxyluteolin (12)] from the latter. Antiproliferative activity of the isolated compounds against murine melanoma (B16F10), human gastric adenocarcinoma (MK-1), and human uterine carcinoma (HeLa) cells was estimated. (+)-Anymol (3), acteoside (4), isoacteoside (5), arenarioside (8), eupafolin (11), and 6-hydroxyluteolin (12) had GI50 values of 10-16 microM against B16F10 cell. Desmethoxycentaureidin (10) and eupafolin (11) showed high inhibitory activity against HeLa cell growth (GI50 9 microM, and 6 microM, respectively). 相似文献
63.
Ursolic acid as a trypanocidal constituent in rosemary 总被引:4,自引:0,他引:4
Abe F Yamauchi T Nagao T Kinjo J Okabe H Higo H Akahane H 《Biological & pharmaceutical bulletin》2002,25(11):1485-1487
The MeOH extract of the leaves of rosemary (Rosmarinus officinalis L.) completely inhibited the motility of cultured epimastigotes of Trypanosoma cruzi at the concentration of 2 mg/ml after 2 h of incubation. Activity-guided fractionation of the MeOH extract has resulted in the isolation of three triterpene acids, betulinic, oleanolic and ursolic acids. Ursolic acid stopped the movement of all T. cruzi epimastigotes at the minimum concentration (MC(100)) of 40 micro g/ml (88 micro M) after 48 h of incubation. Oleanolic acid was less active (MC(100): 250 micro g/ml, 550 micro M) and betulinic acid was practically inactive. 相似文献
64.
Staerk D Lykkeberg AK Christensen J Budnik BA Abe F Jaroszewski JW 《Journal of natural products》2002,65(9):1299-1302
Two known phenanthroindolizidine alkaloids, (-)-(R)-13aalpha-antofine (1) and (-)-(R)-13aalpha-6-O-desmethylantofine (2), and two new natural products, (-)-(R)-13aalpha-secoantofine (3) and (-)-(R)-13aalpha-6-O-desmethylsecoantofine (4), were isolated from Cynanchum vincetoxicum. The structures of all compounds were established by means of NMR methods including COSY, NOESY, HSQC, and HMBC experiments, supported by HRMS and optical rotation data. Cytotoxic activity of the isolated alkaloids, and of three other alkaloids previously isolated from Tylophora tanakae, (-)-(R)-13aalpha-tylophorine (5), (-)-(R)-13aalpha-7-O-desmethyltylophorine (6), and (+)-(S)-13abeta-isotylocrebrine (7), was assessed in vitro using a drug-sensitive KB-3-1 and a multidrug-resistant KB-V1 cancer cell line. Structure-activity relationships in this series of alkaloids are discussed. The IC(50) values of some of the alkaloids are in the low nanomolar range, being thus comparable to the activity of clinically used cytotoxic drugs. Previously reported adverse side effects of these alkaloids could possibly be overcome by modern tissue-specific drug targeting techniques. 相似文献
65.
The combination therapy of Ephedra herb and Loxoprofen caused gastric lesions in mice 总被引:1,自引:0,他引:1
Cho S Hong T Jin GB Yoshino G Miura M Aikawa Y Yasuno F Cyong JC 《The American journal of Chinese medicine》2002,30(4):571-577
The combination therapy of a Kampo formula and an analgesic-antipyretic agent is often used for the common cold in Japan. We investigated the effect of such a combination therapy, using the Ephedra herb, which is a common ingredient of Kakkon-to and Mao-to, and Loxoprofen, a nonsteroidal anti-inflammatory drug (NSAID), on fever induced in an experimental model of mice under strong stress. The combination therapy of Ephedra herb and Loxoprofen caused gastric mucosal lesions and loss of body weight. It is considered that this combination therapy should be avoided because of its adverse effects. 相似文献
66.
67.
Kawabata K Nakai S Miwa M Sugiura T Otsuka Y Shinzato T Hiki Y Tomimatsu I Ushida Y Hosono F Maeda K 《Nephron》2002,90(3):273-281
BACKGROUND/AIM: Employment of treated dialysate as replacement fluid raises concerns about exposure of patients to pyrogenic substances. This study was undertaken to evaluate the safety of treated dialysate as the replacement fluid for push/pull hemodiafiltration. METHODS: In the present study, changes in the expressions of Mac-1 and CD14 on monocytes, which are upregulated by monocyte activation, were analyzed by flow cytometry, and the serum level of sCD14 which elevates by monocyte activation was measured by enzyme-linked immunosorbent assay (ELISA) during treatment in 7 patients on hemodialysis with regenerated cellulose (RC) membrane, polysulfone (PS) membranes and by push/pull hemodiafiltration (HDF) with PS membranes in a cross-over fashion. RESULTS: During hemodialysis with RC, hemodialysis with PS or push/pull hemodiafiltration with PS, both Mac-1 and CD14 expressions on monocytes significantly increased by passing through the artificial kidneys, and, accordingly, the respective values downstream of the artificial kidneys were significantly higher than the predialysis values, even when the lipopolysaccharide level in dialysate was not detectable by Limulus assay. There was no significant variation in serum sCD14 levels during any of the hemodialysis with RC, hemodialysis with PS or push/pull hemodiafiltration. However, during hemodialysis with PS or push/pull hemodiafiltration with PS, changes in Mac-1 and CD14 expression on monocytes were significantly smaller than those during hemodialysis with RC. CONCLUSION: Monocytes are activated to a greater extent during hemodialysis with RC membranes than during push/pull HDF with PS membranes. We consider that push/pull HDF may be safer than hemodialysis with RC membrane and that it is as safe as hemodialysis with the PS membrane in terms of monocyte activation, when pyrogen-free dialysate is employed. 相似文献
68.
Associations of length of employment and working conditions with neck,shoulder and arm pain among nursery school teachers 总被引:1,自引:0,他引:1
Ono Y Imaeda T Shimaoka M Hiruta S Hattori Y Ando S Hori F Tatsumi A 《Industrial health》2002,40(2):149-158
A cross-sectional questionnaire study was carried out on nursery school (NS) teachers in public nursery schools in N city in Japan to determine the magnitude of associations of probable risk factors with neck, shoulder, and arm pain, adjusting for potential confounders in logistic regression models. Of 1438 subjects, responded to the questionnaire, 959 NS teachers in charge of a separate or mixed group of children were subjected to analyses. Prevalence of neck and/or shoulder pain was 33.6%-35.4% in NS teachers in charge of children aged 0, 0-1, 4, and 5 in contrast to 25.0-29.8% in those in charge of children aged 1,2, and 3. The prevalence of neck/shoulder pain tended to increase with the length of employment in all groups classified according to the age of children under care. In a logistic regression model that simultaneously adjusted demographic and personal variables, length of employment and care for children aged 0 in the workplace were found significantly associated with musculoskeletal pain. In further logistic models, pain in the neck/shoulders and arms had associations with some specific variables: care for children aged 0, holding/lifting a child/material, overwork, and poorly supported job situations. The odds ratios for those variables varied from 1.37 to 2.41. This results suggest that pain in the neck/shoulders and arms is induced by a wide variety of risk factors in NS teachers that include high physical workload, long working hours, job demand-support imbalance, and cumulative influence of workloads. 相似文献
69.
70.
We have studied the influence of vitamin C contained in green tea on the lipolysis of well-differentiated 3T3-L1 cells. When mature adipocytes were exposed to vitamin C the triglyceride concentration was decreased (p < 0.05) and the activity of glycerophosphate dehydrogenase, a marker of adipose conversion, was significantly inhibited (p < 0.01). These data suggest that green tea may have a lipolytic activity due to the mechanism by which the vitamin C contained in it inhibits triglyceride accumulation. 相似文献