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51.
Doan Minh Sang Ik Ho Na Dr. Duong Tien Anh Do Thi Mai Dung Nguyen Thi Thu Hang Nguyen T. Phuong-Anh Assoc. Prof. Dr. Pham-The Hai Assoc. Prof. Dr. Dao Thi Kim Oanh Dr. Truong Thanh Tung Soo Jung Lee Joo Hee Kwon Prof. Dr. Jong Soon Kang Prof. Dr. Sang-Bae Han Assoc. Prof. Dr. Dinh Thi Thanh Hai Prof. Dr. Nguyen-Hai Nam 《化学与生物多样性》2023,20(5):e202201030
Herein, we report the design, synthesis and evaluation of novel (E)-3-(3-oxo-4-substituted-3,4-dihydro-2H-benzo[b][1,4]oxazin-6-yl)-N-hydroxypropenamides ( 4 a – i , 7 a – g ) targeting histone deacetylases. Three human cancer cell lines were used to test the cytotoxicity of the synthesized compounds (SW620, colon; PC-3, prostate; NCI−H23, lung cancer); inhibitory activity towards HDAC; anticancer activity; as well as their impact on the cell cycle and apoptosis. As a result, compounds 4 a – i bearing the alkyl substituents seemed to be less potent than the benzyl-containing compounds 7 a – g in all biological assays. Compounds 7 e – f were found to be the most active HDAC inhibitors with IC50 of 1.498±0.020 μM and 1.794±0.159 μM, respectively. In terms of cytotoxicity and anticancer assay, 7 e and 7 f also showed good activity with IC50 values in the micromolar range. In addition, the cell cycle and apoptosis of SW620 were affected by compound 7 f in almost a similar manner to that of reference compound SAHA. Docking assays were carried out for analysis the binding mode and selectivity of this compound toward 8 HDAC isoforms. Overall, our data confirmed that the inhibition of HDAC plays a pivotal role in their anticancer activity. 相似文献
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54.
Hyun Koo Kim Moon Sun Ham Jong Soo Hong Jin Ha Lee Kyung Yu Park Hyeon Yong Lee 《Biotechnology and Bioprocess Engineering》1996,1(1):32-35
A moving aeration-membrane (MAM) bioreactor was employed for the production of 2 μg/mL of tissue type Plasminogen Activator (tPA) in serum free medium from normal human fibroblast cells. This system could maintain high cell density for long periods of steady state conditions in perfusion cultivation. Under normal operating conditions, shear stress was as low as 0.65 dynes/cm2 at the agitation speed of 80 rpm. Even though cell density gradually decreased with increasing agitation speed, tPA production increased linearly with increasing shear stress within a moderate range. This culture system allowed production of 2 μg tPA/mL while maintaining a high cell density of 1.0×107 viable cells/mL. 相似文献
55.
Specimens of basidiomes and/or rhizomorphs ofArmillaria mellea complex and basidiomes ofRhodophyllus abortivus, developing on the same decaying stumps or stems of forest trees, were collected in three forests in Hokkaido. Normal basidiomes
ofR. abortivus were found near to, but free from, the rhizomorphs and/or basidiomes ofArmillaria, while abnormal basidiomes, as carpophoroid forms, were developed on the rhizomorphs ofArmillaria. Of three mycoparasiticArmillaria isolates found withR. abortivus, one was identified asA. gallica and two asA. jezoensis. The isolates ofR. abortivus showed excellent mycelial growth and rhizomorph formation on PDA. However, on MDA, RMDA and BMDA, they showed poor aerial
mycelia growth and no rhizomorphs. In the contrapositional cultures, the growth ofA. gallica was completely inhibited byR. abortivus on PDA but only slightly inhibited on MDA and RMDA. On the other hand, mutual inhibition at a distance was observed on BMDA.
The mycelial growth and rhizomorph formation inA. jezoensis were severely inhibited by the colony ofR. abortivus on PDA, but only slightly inhibited on MDA. On RMDA and BMDA, the colonies of twoArmillaria species andR. abortivus showed mutual inhibition at a distance and apparent rhizomorph formation by bothArmillaria species. 相似文献
56.
Hyung-Joo Jin Jeong–Ha Kim Chul Hyun Sohn R.E. DeWreede Tae–Joo Choi G.H.N. Towers J.B. Hudson Yong–Ki Hong 《Journal of applied phycology》1997,9(4):383-388
Fifty-nine species of marine macrophytes from the coasts of British Columbia, Canada and Korea have been screened for the
presence of PCR inhibitors, namely inhibitors of Taq DNA polymerase. Eleven of the species displayed some inhibitor activity.
At the concentration of 5 μg of methanol extract in 25μL reaction mixture of PCR containing 1.5 unit of Taq DNA polymerase,
one (Ulva sp.) of 8 Chlorophyta, eight (Colpomenia bullosa, Ecklonia cava, Endarachne binghamiae, Fucus distichus, Hizikia
fusiformis, Sargassum confusum, Sargassum sagamianum, and Sargassum thunbergii) of 28 Phaeophyta, and one (Symphyocladia latiuscula)
of 34 Rhodophyta showed inhibition in PCR amplification. In the case of the water extract, two (Cladophora columbiana, Ulva
sp.) Chlorophyta, seven (Endarachne binghamiae, Fucus distichus, Hizikia fusiformis, Sargassum confusum, Sargassum sagamianum,
Sargassum horneri, Scytosiphon dotyi) Phaeophyta, no Rhodophyta and one (Phyllospadix scouleri) seagrass showed inhibition
in PCR amplification. the methanol fraction of Sargassum confusum and the water fraction of Fucus gardneri (mid–intertidal)
have been found to inhibit PCR at level as low as 0.5 μg in 25μL of PCR reaction mixture.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
57.
B. Bhattacharjee Gynheung An H. S. Gupta 《Journal of plant biochemistry and biotechnology.》1997,6(2):69-73
We report production of fertile transgenic Indica rice plants by transferring a chimaeric construct consisting of promoter, first exon and intron of maize ubiquitin gene (Ubi-1) and the coding sequences of the bar gene from Streptomyces hygroscopicus to the rice protoplasts through electroporation. In total, 11 plants were regenerated. All of them were fertile and set seeds on maturity. These plants were resistant to high concentration of PPT (400 mg l?1) which was otherwise toxic to the untransformed controls. The gene was inherited to the progenies of the five plants in Mendelian ratio. 相似文献
58.
Mutational analysis of the three cysteines and active-site aspartic acid 103 of ketosteroid isomerase from Pseudomonas putida biotype B. 下载免费PDF全文
In order to clarify the roles of three cysteines in ketosteroid isomerase (KSI) from Pseudomonas putida biotype B, each of the cysteine residues has been changed to a serine residue (C69S, C81S, and C97S) by site-directed mutagenesis. All cysteine mutations caused only a slight decrease in the k(cat) value, with no significant change of Km for the substrate. Even modification of the sulfhydryl group with 5,5'-dithiobis(2-nitrobenzoic acid) has almost no effect on enzyme activity. These results demonstrate that none of the cysteines in the KSI from P. putida is critical for catalytic activity, contrary to the previous identification of a cysteine in an active-site-directed photoinactivation study of KSI. Based on the three-dimensional structures of KSIs with and without dienolate intermediate analog equilenin, as determined by X-ray crystallography at high resolution, Asp-103 was found to be located within the range of the hydrogen bond to the equilenin. To assess the role of Asp-103 in catalysis, Asp-103 has been replaced with either asparagine (D103N) or alanine (D103A) by site-directed mutagenesis. For D103A mutant KSI there was a significant decrease in the k(cat) value: the k(cat) of the mutant was 85-fold lower than that of the wild-type enzyme; however, for the D103N mutant, which retained some hydrogen bonding capability, there was a minor decrease in the k(cat) value. These findings support the idea that aspartic acid 103 in the active site is an essential catalytic residue involved in catalysis by hydrogen bonding to the dienolate intermediate. 相似文献
59.
Masayuki Kobayashi Marc Garcia-Elias Ladislav Nagy Marco J. P. F. Ritt Kai-Nan An William P. Cooney Ronald L. Linscheid 《Journal of biomechanics》1997,30(11-12)
The changes in carpal bone alignment secondary to the aplication of an axial compressive load through the major wrist motor tendons while the wrist is kept in neutral position (isometric loading) have been investigated on 13 fresh cadaver specimens using a biplanar radiographic method of kinematic analysis. The scaphoid, lunate and triquetrum rotate an average of 5.1, 4.2 and 3.8°, respectively, around different ‘screw displacement axes’, all implying flexion, radial deviation and supination. Based on these findings, a new interpretation of the mechanism by which the wrist remains stable under physiologic loads is provided. 相似文献
60.