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Linda Saxe Einbond Ye Wen-Cai Kan He Hsan-au Wu Erica Cruz Marc Roller Fredi Kronenberg 《Phytomedicine》2008,15(6-7):504-511
The purpose of this report is to explore the growth inhibitory effect of extracts and compounds from black cohosh and related Cimicifuga species on human breast cancer cells and to determine the nature of the active components. Black cohosh fractions enriched for triterpene glycosides and purified components from black cohosh and related Asian species were tested for growth inhibition of the ER− Her2 overexpressing human breast cancer cell line MDA-MB-453. Growth inhibitory activity was assayed using the Coulter Counter, MTT and colony formation assays.Results suggested that the growth inhibitory activity of black cohosh extracts appears to be related to their triterpene glycoside composition. The most potent Cimicifuga component tested was 25-acetyl-7,8-didehydrocimigenol 3-O-β-d-xylopyranoside, which has an acetyl group at position C-25. It had an IC50 of 3.2 μg/ml (5 μM) compared to 7.2 μg/ml (12.1 μM) for the parent compound 7,8-didehydrocimigenol 3-O-β-d-xylopyranoside. Thus, the acetyl group at position C-25 enhances growth inhibitory activity.The purified triterpene glycoside actein (β-d-xylopyranoside), with an IC50 equal to 5.7 μg/ml (8.4 μM), exhibited activity comparable to cimigenol 3-O-β-d-xyloside. MCF7 (ER+Her2 low) cells transfected for Her2 are more sensitive than the parental MCF7 cells to the growth inhibitory effects of actein from black cohosh, indicating that Her2 plays a role in the action of actein. The effect of actein on Her2 overexpressing MDA-MB-453 and MCF7 (ER+Her2 low) human breast cancer cells was examined by fluorescent microscopy. Treatment with actein altered the distribution of actin filaments and induced apoptosis in these cells.These findings, coupled with our previous evidence that treatment with the triterpene glycoside actein induced a stress response and apoptosis in human breast cancer cells, suggest that compounds from Cimicifuga species may be useful in the prevention and treatment of human breast cancer. 相似文献
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Lucia S. Mukhtarova Fredi Brühlmann Mats Hamberg Bulat I. Khairutdinov Alexander N. Grechkin 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2018,1863(10):1316-1322
Hydroperoxide lyases (HPLs) of the CYP74 family (P450 superfamily) are widely distributed enzymes in higher plants and are responsible for the stress-initiated accumulation of short-chain aldehydes. Fatty acid hydroperoxides serve as substrates for HPLs; however, details of the HPL-promoted conversion are still incompletely understood. In the present work, we report first time the micropreparative isolation and the NMR structural studies of fatty acid hemiacetal (TMS/TMS), the short-lived HPL product. With this aim, linoleic acid 9(S)?hydroperoxide (9(S)?HPOD) was incubated with recombinant melon hydroperoxide lyase (CmHPL, CYP74C2) in a biphasic system of water/hexane for 60?s at 0?°C, pH?4.0. The hexane layer was immediately decanted and vortexed with a trimethylsilylating mixture. Analysis by GC–MS revealed a major product, i.e. the bis-TMS derivative of a hemiacetal which was conclusively identified as 9?hydroxy?9?[(1′E,3′Z)?nonadienyloxy]?nonanoic acid by NMR-spectroscopy. Further support for the hemiacetal structure was provided by detailed NMR-spectroscopic analysis of the bis-TMS hemiacetal generated from [13C18]9(S)?HPOD in the presence of CmHPL. The results obtained provide incontrovertible evidence that the true products of the HPL group of enzymes are hemiacetals, and that the short-chain aldehydes are produced by their rapid secondary chain breakdown. Therefore, we suggest replacing the name “hydroperoxide lyase”, which does not reflect the factual isomerase (intramolecular oxidoreductase) activity, with “hemiacetal synthase” (HAS). 相似文献
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Michael J. Balick Fredi Kronenberg Andreana L. Ososki Marian Reiff Adriane Fugh-Berman O’Connor Bonnie Maria Roble Patricia Lohr Daniel Atha 《Economic botany》2000,54(3):344-357
This paper examines the use of medicinal plants by Latino healers in New York City to treat various women’s illnesses. Eight Latino healers collaborated on the study through consultations with female patients who had one of the following conditions as diagnosed by biomedically trained physicians: uterine fibroids, hot flashes, menorrhagia, or endometriosis. The study identified a total of 67 plant species prescribed by the healers in the form of mixtures or as individual plants. Voucher specimens were collected from local botánicas and identified by specialists at The New York Botanical Garden. Studies of immigrant traditional healers and the plants they use in an urban setting can provide interesting ethnobotanical data and information to assist in diagnosing conditions and contributing to treatment of patients from Latino as well as non-Latino communities. 相似文献
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A new PrfA-regulated gene of Listeria monocytogenes encoding a small, secreted protein which belongs to the family of internalins 总被引:8,自引:5,他引:3
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Joerg H Janett F Schlatt S Mueller S Graphodatskaya D Suwattana D Asai M Stranzinger G 《Biology of reproduction》2003,69(6):1940-1944
Germ cell transplantation is a technique that transfers donor testicular cells into recipient testes. A population of germ cells can colonize the recipient testis, initiate spermatogenesis, and produce sperm capable of fertilization. In the present study, a nonmosaic Klinefelter bull was used as a germ cell recipient. The donor cell suspension was introduced into the rete testis using ultrasound-guided puncture. A pulsatile administration of GnRH was performed to stimulate spermatogenesis. The molecular approach to detect donor cells was done by a quantitative polymerase chain reaction with allele discrimination based on a genetic mutation between donor and recipient. Therefore, a known genetic mutation, associated with coat-color phenotype, was used to calculate the ratio of donor to recipient cells in the biopsy specimens and ejaculates for 10 mo. After slaughtering, meiotic preparations were performed. The injected germ cells did not undergo spermatogenesis. Six months after germ cell transplantation, the donor cells were rejected, which indicates that the donor cells could not incorporate in the testis. The hormone stimulation showed that the testosterone-producing Leydig cells were functionally intact. Despite subfertility therapy, neither the recipient nor the donor cells underwent spermatogenesis. Therefore, nonmosaic Klinefelter bulls are not suitable as germ cell recipients. Future germ cell recipients in cattle could be mosaic Klinefelters, interspecies hybrids, bulls with Sertoli cell-only syndrome, or bulls with disrupted germ cell migration caused by RNA interference. 相似文献
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Pectinolytic Enzymes from Actinomycetes for the Degumming of Ramie Bast Fibers 总被引:5,自引:1,他引:4
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Fredi Brühlmann Kwi Suk Kim Wolfgang Zimmerman Armin Fiechter 《Applied microbiology》1994,60(6):2107-2112
Actinomycetes isolated from 10 different soil and compost samples were screened for production of pectinolytic enzyme activities when grown on pectin-containing solid and liquid media. Pectinolytic enzymes, detected by using plate diffusion tests with a medium containing ramie (Boehmeria nivea) plant material as the sole carbon source, were mainly pectate lyases, but low activities of pectinesterases were also observed. Polygalacturonases and polymethylgalacturonases were not produced. Multiple forms of pectate lyases were detected in the culture supernatants of some of the strains by using the zymogram technique of isoelectric focusing gels. Xylanolytic and cellulolytic activities were always found to be associated with pectinolytic activities. None of the pectinolytic enzymes were produced in a medium with glucose as the sole carbon source. Treatment of ramie bast fibers with crude enzyme preparations from a selection of strains showed a good correlation between the pectate lyase activity applied and the degumming effect, resulting in good separation of the bast fibers. 相似文献
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Díaz FA Martínez RA 《Biomédica : revista del Instituto Nacional de Salud》2005,25(3):422-3; author reply 423-4
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