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271.
A series of backbone modified and sulfonic acid replacement analogs of our topical, clinical candidate (iii) were synthesized. Their antimicrobial activities and aqueous stabilities at pH 4 and pH 7 were determined, and has led us to identify quaternary ammonium N,N-dichloroamines as a new class of topical antimicrobial agents.  相似文献   
272.
Thanks to the synthetic biology, the laborious and restrictive procedure for producing a target protein in living microorganisms by biotechnological approaches can now experience a robust, pliant yet efficient alternative. The new system combined with lab-on-chip microfluidic devices and nanotechnology offers a tremendous potential envisioning novel cell-free formats such as DNA brushes, hydrogels, vesicular particles, droplets, as well as solid surfaces. Acting as robust microreactors/microcompartments/minimal cells, the new platforms can be tuned to perform various tasks in a parallel and integrated manner encompassing gene expression, protein synthesis, purification, detection, and finally enabling cell-cell signaling to bring a collective cell behavior, such as directing differentiation process, characteristics of higher order entities, and beyond. In this review, we issue an update on recent cell-free protein synthesis (CFPS) formats. Furthermore, the latest advances and applications of CFPS for synthetic biology and biotechnology are highlighted. In the end, contemporary challenges and future opportunities of CFPS systems are discussed.  相似文献   
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Abstract

The synthesis of a DNA-PHONA-PNA chimeric molecule using the Mmt protection strategy is described. The chimeric oligomer shows duplex binding properties that are comparable to PNA. Obviously, PHONA building blocks can be incorporated into PNAs without distortion of the PNA structure

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276.
In this Letter we describe the optimization of an aminopurine lead (1) with modest potency and poor overall kinase selectivity which led to the identification of a series of potent, selective JNK inhibitors. Improvement in kinase selectivity was enabled by introduction of an aliphatic side chain at the C-2 position. CC-359 (2) was selected as a potential clinical candidate for diseases manifested by ischemia reperfusion injury.  相似文献   
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The performance of one stage anaerobic/aerobic processes for the biological treatment of synthetic wastewaters containing Acid Red 18 was studied. In addition, a method for evaluating dye mineralization using lumped parameters was investigated. The selected initial dye concentrations were 0, 35, 70, 140, and 280 mg/L, in reactors R1 ~ R5, respectively. This study showed that average COD removal was not lower than 85% while the remaining COD originated from Acid Red 18 and its degradation products. The majority of the dye removal occurred in the anaerobic phases and the aerobic phase contributions were insignificant. The kinetics data of dye removal showed that the increase in initial dye concentration (35 ~ 280 mg/L) caused a decrease in first-order kinetic rate constants (0.0593 ~ 0.0384/h). The overall mineralization of AR 18 dye was at least 44, 35, 13, and 0% in R2 ~ R5, respectively. Increase in initial dye concentrations had no significant effect on sludge characteristics.  相似文献   
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Glioblastoma multiform (GBM) is a highly malignant brain tumor. Bevacizumab is a recent therapy for stopping tumor growth and even shrinking tumor through inhibition of vascular development (angiogenesis). This paper presents a non-invasive approach based on image analysis of multi-parametric magnetic resonance images (MRI) to predict response of GBM to this treatment. The resulting prediction system has potential to be used by physicians to optimize treatment plans of the GBM patients. The proposed method applies signal decomposition and histogram analysis methods to extract statistical features from Gd-enhanced regions of tumor that quantify its microstructural characteristics. MRI studies of 12 patients at multiple time points before and up to four months after treatment are used in this work. Changes in the Gd-enhancement as well as necrosis and edema after treatment are used to evaluate the response. Leave-one-out cross validation method is applied to evaluate prediction quality of the models. Predictive models developed in this work have large regression coefficients (maximum R 2 = 0.95) indicating their capability to predict response to therapy.  相似文献   
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