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1.
Arthrographis kalrae is a dimorphic, cosmopolitan and neurotropic fungus that has been described as a rare human pathogen. This study investigated the hemolytic and cytotoxic activities of A. kalrae cell-free antigens (CFAs). Total CFAs and their Sephadex chromatography fractions were tested on mouse erythrocytes for hemolysis and on the P3U1 cell line for cytotoxicity. Hemolytic and cytotoxic activities were detected in distinct molecular mass (MM) fractions. Additionally, antibodies against isogenic erythrocytes sensitized with CFAs (anti-E-CFAs) inhibited hemolysis but not cytotoxicity. Hemolysis was not affected by heating, and a higher reactivity was detected in the carbohydrate-rich fractions, which decreased after reduction by periodate treatment. The pioneering nature of this work is due to the demonstration of the cytotoxic activity in A. kalrae and the suggestion that this activity may be due to molecules distinct from the hemolytic factor, with the latter potentially being a component with a high MM.  相似文献   
2.
用透射电镜观察了镍化合物对蚕豆和冬小麦根端细胞超微结构的影响,结果表明,硫酸镍不同程度地引起蚕豆和冬小麦细胞的损伤。在15μg/ml浓度下,镍化合物可诱导蚕豆根端细胞核变形,液泡内有凝聚物断续性附着于液泡膜内侧。在相同浓度下,硫酸镍对冬小麦根端细胞内部结构影响较小。在80μg/ml浓度下,冬小麦细胞液泡有凝聚性变化,质壁有轻度分离。而蚕豆在此浓度处理下,核固缩,核膜崩解,细胞内部电子密度明显升高,结构呈凝聚状,欠清晰,液泡出现凝聚性变化,质壁出现重度分离。以上结果意味着镍化合物对蚕豆的损伤程度要高于对冬小麦的损伤程度。  相似文献   
3.
 Taiwania (Taiwania cryptomerioides Hayata), native to Taiwan, is one of the most economically important tree species grown there. In this article we summarize the current results of phytochemistry and bioactivity of Taiwania extracts, including antifungal, antitermite, antibacterial, and antimite activities as well as cytotoxicity against three tumor cells. The resources of Taiwania are also addressed. Received: January 23, 2002 / Accepted: March 8, 2002 Acknowledgment The authors thank the National Science Council of R.O.C. for financial support (NSC-90-2313-B-002-344). Correspondence to:S.-T. Chang  相似文献   
4.
Four new oligostilbenes, macrostachyols A-D (1-4) along with six known stilbenoids (5-10), were isolated from the roots of Gnetum macrostachyum. These compounds were also evaluated for their cytotoxicity towards HeLa and KB cell lines. Only compound 4 showed the significant cytotoxicity to HeLa cells with IC50 value of 4.13 μM.  相似文献   
5.
A new dimeric aporphine, artabotrysine along with five known compounds was isolated from the roots of Artabotrys spinosus. Their structures were fully established on the basis of spectral evidence. All isolated compounds were evaluated for their cytotoxicity on HeLa and KB cells.  相似文献   
6.
Bioassay-guided fractionation of the cytotoxic ethyl acetate extract from the stems of Dasymaschalon blumei (Annonaceae) led to the isolation of four aristololactam alkaloids, including the hitherto unknown 3,5-dihydroxy-2,4-dimethoxyaristolactam (1), as well as the three known compounds, aristolactam BI, goniopedaline, and griffithinam. Additionally, the cytotoxic extract from the combined leaves and twigs of the same plant yielded three known oxoaporphine alkaloids, oxodiscoguattine, dicentrinone, and duguevalline. The structures of aristolactams and oxoaporphine alkaloids were elucidated on the basis of spectroscopic methods. All isolates were evaluated for cytotoxicity against a panel of mammalian cancer cell lines and a noncancerous human embryonic kidney cell Hek 293.  相似文献   
7.
A new oxazole (1) was obtained from Chinese insect medicine Aspongopus chinensis, along with three known N-acetyldopamine derivatives (2-4). Their structures were determined on the basis of NMR and ESI-MS analyses. The possible biosynthetic pathways of the isolated compounds are discussed. Cytotoxicities of those compounds against 10 selected cancer cells were measured in vitro.  相似文献   
8.
Hai W  Cheng H  Zhao M  Wang Y  Hong L  Tang H  Tian X 《Fitoterapia》2012,83(4):759-764
Bioassay-guided fractionation of the n-BuOH extract of the roots of Clematis argentilucida led to the isolation of two new triterpenoid saponins along with a known one, cussonside B (3). By extensive spectral analysis and chemical evidences, the structures of the two new saponins were determined to be 3β-O-[β-D-ribopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl] hederagenin-11,13-dien-28-oic acid (1) and 3β-O-{β-D-ribopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-β-D-xylopyranosyl} oleanolic acid (2), respectively. Saponin 1 is the first example of triterpenoid saponins with two double bonds located at C-11 and C-13 in the aglycone from the genus Clematis. The two new saponins exhibited significant cytotoxicity against human leukemia HL-60 cell lines, human hepatocellular carcinoma Hep-G2 cell lines and human glioblastoma U251MG cell lines with a range of IC(50) values from 2.74 to 25.40μM, while 3 showed inactivity against all of the three cancer cell lines.  相似文献   
9.
In the course of searching for cytotoxic terpenoids from medicinal plants in China, two new eudesmane sesquiterpenoids, 5α-hydroxy-13-methoxy-7αH,11αH-eudesm-4(15)-en-12,8β-lactone (1) and 1β-hydroxy-7αH,11αH-eudesm-4(15)-en-12,8β-lactone (2), along with fourteen known sesquiterpenoids were isolated from the whole plant of Carpesium divaricatum. The structures of new compounds were determined using spectroscopic methods, including IR, HRESIMS, and 1D and 2D NMR spectroscopy. The cytotoxicity of selected sesquiterpene lactones against human oral epidermoid carcinoma (KB), human breast cancer (MCF-7) and human hepatoma (HepG-2) cells was also evaluated by MTT method.  相似文献   
10.
A new cardenolide tupichinolide (1) and a new steroidal saponin tupichinin A (2), together with seven known compounds, were isolated from the rhizomes of Tupistra chinensis. Their structures were established using spectroscopic analysis and chemical methods. Compound 1 was the first cardenolide isolated from Tupistra chinensis and exhibited potent cytotoxicity against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480.  相似文献   
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