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151.
Introduction – Application of on‐line solid‐phase extraction (SPE) as an interface between HPLC and NMR has gained great improvement in solving sensitivity problems and signal interferences by the eluents. Objective – Rapid analysis and characterisation by HPLC‐SPE‐NMR and LC/MS of the arylnaphthalene‐type lignans present in Phyllanthus myrtifolius and the minor stilbenoids present in the polyphenol‐rich fraction from the ethanol extract of the seeds of Syagrus romanzoffiana. Methodology – Pretreatment of fractions by liquid–liquid partitioning, followed by Sephadex LH‐20 fractionation, was found very useful to facilitate the focusing and analysis of the polyphenolic fraction. HPLC‐DAD‐SPE‐NMR (400 MHz and 600 MHz) analysis was carried out using an Agilent 1100 liquid chromatography, followed by a Prospekt 2 automated solid‐phase extraction unit, containing 96 HySphere‐Resin GP cartridges (10 × 2 mm, 10–12 µm), which was connected to a 120 or 60 µL LC probe. Results – Seven arylnaphthalene‐type lignans from the chloroform‐soluble fraction of P. myrtifolius and nine stilbenoids from a polyphenol‐rich butanol‐soluble fraction of the seeds of S. romanzoffiana were characterised. Conclusion – HPLC‐SPE‐NMR associated with HR‐ESI/MS, which consumed only analytical amounts of partially purified mixtures, was demonstrated to be a good tool for rapid screening of both known and new natural products. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
152.
Shie JL Chang CC Chang CY Tzeng CC Wu CY Lin KL Tseng JY Yuan MH Li HY Kuo CH Yu YJ Chang LC 《Bioresource technology》2011,102(23):11011-11017
This study examined the effects of additives of potassium carbonate (K2CO3) and zinc oxide (ZnO) on the pyrolysis of waste sunflower-oil cake using a 60 kW pilot-scale plasma torch reactor. The major gaseous products were CO and H2. The productions of CO and CH4 increased while that of H2 decreased with the addition of K2CO3. The use of ZnO reduced while enhanced the formation of CO and H2, respectively. In order to match the appeal of resource reutilization, one can use the waste K2CO3 resulted from the sorption of CO2 with KOH in greenhouse gas control and the waste ZnO obtained from the melting process as additives for the co-pyrolysis of sunflower-oil cake, yielding fuels rich in CO and H2, respectively. 相似文献
153.
Wang LY Tseng WC Wu TS Kaneko K Takayama H Kimura M Yang WC Wu JB Juang SH Wong FF 《Bioorganic & medicinal chemistry letters》2011,21(18):5358-5362
An efficient 1,3-dipolar cycloaddition method was performed for the synthesis of a series of monofluoro- and trifluoromethane-3,5-disubstituted 1,2,4-triazoles. This efficient cycloaddition method was to react hydrazonoyl hydrochlorides with a series of aldehydes in the presence of NEt(3) as catalytic basic agent to provide the corresponding product in 28-94%. Their growth inhibitory results against cancer cells indicated that some of the fluorine- and trifluoromethane-containing compounds could effectively inhibit the growth of NCI-H226 and T-cell leukemia (Jurkat) cells. Among the compounds, trifluoromethane-containing 1,2,4-triazoles possessed the five-membered ring groups on the C-5 position of the triazolic ring, including cyclopentyl, 3-furyl, 3-thienyl, and 2-pyrrolyl, possessed the significant inhibitory activity for NCI-H226 cancer cells. 相似文献
154.
Yu-Fen Tseng Chien-Chih Wang Shuen-Kuei Liao Ching-Kai Chuang Wei-June Chen 《Journal of biomedical science》2011,18(1):20
Japanese encephalitis (JE) virus is the most common cause of epidemic viral encephalitis in the world. The virus mainly infects
neuronal cells and causes an inflammatory response after invasion of the parenchyma of the brain. The death of neurons is
frequently observed, in which demyelinated axons are commonly seen. The mechanism that accounts for the occurrence of demyelination
is ambiguous thus far. With a mouse model, the present study showed that myelin-specific antibodies appeared in sera, particularly
in those mice with evident symptoms. Meanwhile, specific T cells proliferating in response to stimulation by myelin basic
protein (MBP) was also shown in these mice. Taken together, our results suggest that autoimmunity may play an important role
in the destruction of components, e.g., MBP, of axon-surrounding myelin, resulting in demyelination in the mouse brain after infection with the JE virus. 相似文献
155.
Chia-Chen Hsu Yu-Wei Leu Min-Jen Tseng Kuan-Der Lee Tzen-Yu Kuo Jia-Yi Yen Yen-Ling Lai Yi-Chen Hung Wei-Sheng Sun Chien-Min Chen Pei-Yi Chu Kun-Tu Yeh Pearlly S Yan Yu-Sun Chang Tim H-M Huang Shu-Huei Hsiao 《Journal of biomedical science》2011,18(1):12
Background
The Cdc42-interacting protein-4, Trip10 (also known as CIP4), is a multi-domain adaptor protein involved in diverse cellular processes, which functions in a tissue-specific and cell lineage-specific manner. We previously found that Trip10 is highly expressed in estrogen receptor-expressing (ER+) breast cancer cells. Estrogen receptor depletion reduced Trip10 expression by progressively increasing DNA methylation. We hypothesized that Trip10 functions as a tumor suppressor and may be involved in the malignancy of ER-negative (ER-) breast cancer. To test this hypothesis and evaluate whether Trip10 is epigenetically regulated by DNA methylation in other cancers, we evaluated DNA methylation of Trip10 in liver cancer, brain tumor, ovarian cancer, and breast cancer.Methods
We applied methylation-specific polymerase chain reaction and bisulfite sequencing to determine the DNA methylation of Trip10 in various cancer cell lines and tumor specimens. We also overexpressed Trip10 to observe its effect on colony formation and in vivo tumorigenesis.Results
We found that Trip10 is hypermethylated in brain tumor and breast cancer, but hypomethylated in liver cancer. Overexpressed Trip10 was associated with endogenous Cdc42 and huntingtin in IMR-32 brain tumor cells and CP70 ovarian cancer cells. However, overexpression of Trip10 promoted colony formation in IMR-32 cells and tumorigenesis in mice inoculated with IMR-32 cells, whereas overexpressed Trip10 substantially suppressed colony formation in CP70 cells and tumorigenesis in mice inoculated with CP70 cells.Conclusions
Trip10 regulates cancer cell growth and death in a cancer type-specific manner. Differential DNA methylation of Trip10 can either promote cell survival or cell death in a cell type-dependent manner. 相似文献156.
Calocetriol ( 1 ), diacetylcalocediol ( 2 ), and ferrugimenthenol ( 3 ) were isolated from the bark of Calocedrus macrolepis var. formosana. Among them, 1 and 2 are secoabietane‐type diterpenoids, and 3 , with a novel C20 C10 skeleton, is classified as a meroterpenoid. The structures of 1 – 3 were elucidated by spectroscopic analyses, and their biological activities were also evaluated. Compound 3 exhibited significant cytotoxic activity against human oral epidermoid carcinoma KB cells with an IC50 value of 9.0±0.1 μM . 相似文献
157.
Pao PC Huang NK Liu YW Yeh SH Lin ST Hsieh CP Huang AM Huang HS Tseng JT Chang WC Lee YC 《Cell death and differentiation》2011,18(11):1791-1804
Znf179 is a member of the RING finger protein family. During embryogenesis, Znf179 is expressed in a restricted manner in the brain, suggesting a potential role in nervous system development. In this report, we show that the expression of Znf179 is upregulated during P19 cell neuronal differentiation. Inhibition of Znf179 expression by RNA interference significantly attenuated neuronal differentiation of P19 cells and a primary culture of cerebellar granule cells. Using a microarray approach and subsequent functional annotation analysis, we identified differentially expressed genes in Znf179-knockdown cells and found that several genes are involved in development, cellular growth, and cell cycle control. Flow cytometric analyses revealed that the population of G0/G1 cells decreased in Znf179-knockdown cells. In agreement with the flow cytometric data, the number of BrdU-incorporated cells significantly increased in Znf179-knockdown cells. Moreover, in Znf179-knockdown cells, p35, a neuronal-specific Cdk5 activator that is known to activate Cdk5 and may affect the cell cycle, and p27, a cell cycle inhibitor, also decreased. Collectively, these results show that induction of the Znf179 gene may be associated with p35 expression and p27 protein accumulation, which lead to cell cycle arrest in the G0/G1 phase, and is critical for neuronal differentiation of P19 cells. 相似文献
158.
159.
The nuclear envelope of metazoans disassembles during mitosis and reforms in late anaphase after sister chromatids have well separated. The coordination of these mitotic events is important for genome stability, yet the temporal control of nuclear envelope reassembly is unknown. Although the steps of nuclear formation have been extensively studied in vitro using the reconstitution system from egg extracts, the temporal control can only be studied in vivo. Here, we use time-lapse microscopy to investigate this process in living HeLa cells. We demonstrate that Cdk1 activity prevents premature nuclear envelope assembly and that phosphorylation of the inner nuclear membrane protein lamin B receptor (LBR) by Cdk1 contributes to the temporal control. We further identify a region in the nucleoplasmic domain of LBR that inhibits premature chromatin binding of the protein. We propose that this inhibitory effect is partly mediated by Cdk1 phosphorylation. Furthermore, we show that the reduced chromatin-binding ability of LBR together with Aurora B activity contributes to nuclear envelope breakdown. Our studies reveal for the first time a mechanism that controls the timing of nuclear envelope reassembly through modification of an integral nuclear membrane protein. 相似文献
160.