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161.
Youssef D Nichols CE Cameron TS Balzarini J De Clercq E Jha A 《Bioorganic & medicinal chemistry letters》2007,17(20):5624-5629
A series of novel cyclic analogues of curcumin were synthesized and analyzed for in vitro cytostatic activity. Condensation of 2-acetylcycloalkanones with a variety of aromatic aldehydes resulted in the formation of 2-arylidene-6-(3-arylacryoyl)-cycloalkanone derivatives. A number of these analogues were found to have significant anticancer activity against representative murine and human cancer cell lines during in vitro bioassays. This corroborated with in vitro cytostatic activity against a panel of 60 cell lines studied at the National Cancer Institute (USA). 相似文献
162.
Glucosyltransferases (GTFs, EC.2.4.1.5) are bacterial enzymes that catalyze the polymerization of glucose residues from sucrose,
leading to the production of high molecular weight glucan with α-1,3 /α-1,6 linkages. Such glucans, with many potential food
and industrial applications, do not normally exist in higher plants. We fused a mutant form of the gtfD gene from Sreptococcus mutans with the maize (Zea mays L.) chloroplastic Brittle 1 transit peptide for amyloplast targeting. This construct, driven by the ubiquitin promoter, was
introduced into maize by Agrobacterium-mediated transformation. We developed a novel HPLC-based method that enabled us differentially to distinguish transgene glucan
from other endogenous polysaccharides in maize kernels. Using this method, we screened over 100 transgenic plants for the
presence of GTF-produced glucan whose content varied between 0.8 and 14% of dry weight in the mature transgenic seeds. The
mature transgenic plants were indistinguishable from wildtype plants in growth rate and morphology. Furthermore, starch granule
size in the transgenic maize kernel was unaffected by the accumulation of the foreign polysaccharide. Mutation in Sh2, which encodes a subunit of ADP-glucose pyrophosphorylase, had no effect on glucan accumulation caused by gtfD expression. Our results indicated that high levels of novel carbohydrate polymer can be accumulated in crop plants through
transgene technology. 相似文献
163.
Robust hit identification by quality assurance and multivariate data analysis of a high-content, cell-based assay 总被引:1,自引:0,他引:1
Dürr O Duval F Nichols A Lang P Brodte A Heyse S Besson D 《Journal of biomolecular screening》2007,12(8):1042-1049
Recent technological advances in high-content screening instrumentation have increased its ease of use and throughput, expanding the application of high-content screening to the early stages of drug discovery. However, high-content screens produce complex data sets, presenting a challenge for both extraction and interpretation of meaningful information. This shifts the high-content screening process bottleneck from the experimental to the analytical stage. In this article, the authors discuss different approaches of data analysis, using a phenotypic neurite outgrowth screen as an example. Distance measurements and hierarchical clustering methods lead to a profound understanding of different high-content screening readouts. In addition, the authors introduce a hit selection procedure based on machine learning methods and demonstrate that this method increases the hit verification rate significantly (up to a factor of 5), compared to conventional hit selection based on single readouts only. 相似文献
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165.
Nonlinear optical imaging to evaluate the impact of obesity on mammary gland and tumor stroma 总被引:2,自引:0,他引:2
Obesity is an established risk factor for breast cancer incidence and mortality. However, the mechanism that links obesity to tumorigenesis is not well understood. Here we combined nonlinear optical imaging technologies with an early-onset diet-induced obesity breast cancer animal model to evaluate the impact of obesity on the composition of mammary gland and tumor stroma. Using coherent anti-Stokes Raman scattering and second harmonic generation on the same platform, we simultaneously imaged mammary adipocytes, blood capillaries, collagen fibrils, and tumor cells without any labeling. We observed that obesity increases the size of lipid droplets of adipocytes in mammary gland and collagen content in mammary tumor stroma, respectively. Such impacts of obesity on mammary gland and tumor stroma could not be analyzed using standard two-dimensional histologic evaluation. Given the importance of mammary stroma to the growth and migration of tumor cells, our observation provides the first imaging evidence that supports the relationship between obesity and breast cancer risk. 相似文献
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168.
David J. Aceti Craig A. Bingman Russell L. Wrobel Ronnie O. Frederick Shin-ichi Makino Karl W. Nichols Sarata C. Sahu Lai F. Bergeman Paul G. Blommel Claudia C. Cornilescu Katarzyna A. Gromek Kory D. Seder Soyoon Hwang John G. Primm Grzegorz Sabat Frank C. Vojtik Brian F. Volkman Zsolt Zolnai George N. Phillips Jr. John L. Markley Brian G. Fox 《Journal of structural and functional genomics》2015,16(2):67-80
169.
170.
Koh A Riccio DA Sun B Carpenter AW Nichols SP Schoenfisch MH 《Biosensors & bioelectronics》2011,28(1):17-24
Despite clear evidence that polymeric nitric oxide (NO) release coatings reduce the foreign body response (FBR) and may thus improve the analytical performance of in vivo continuous glucose monitoring devices when used as sensor membranes, the compatibility of the NO release chemistry with that required for enzymatic glucose sensing remains unclear. Herein, we describe the fabrication and characterization of NO-releasing polyurethane sensor membranes using NO donor-modified silica vehicles embedded within the polymer. In addition to demonstrating tunable NO release as a function of the NO donor silica scaffold and polymer compositions and concentrations, we describe the impact of the NO release vehicle and its release kinetics on glucose sensor performance. 相似文献