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131.
Zorro-LNA (Zorro) is a newly developed, oligonucleotide (ON)-based, Z-shaped construct with the potential of specific binding to each strand of duplex DNA. The first-generation Zorros are formed by two hybridized LNA/DNA mixmers (2-ON Zorros) and was hypothesized to strand invade. We have now established a method, which conclusively demonstrates that an LNA ON can strand invade into duplex DNA. To make Zorros smaller in size and easier to design, we synthesized 3′–5′–5′–3′ single-stranded Zorro-LNA (ssZorro) by using both 3′- and 5′-phosphoramidites. With ssZorro, a significantly greater extent and rate of double-strand invasion (DSI) was obtained than with conventional 2-ON Zorros. Introducing hydrophilic PEG-linkers connecting the two strands did not significantly change the rate or extent of DSI as compared to ssZorro with a nucleotide-based linker, while the longest alkyl-chain linker tested (36 carbons) resulted in a very slow DSI. The shortest alkyl-chain linker (3 carbons) did not reduce the extent of DSI of ssZorro, but significantly decreased the DSI rate. Collectively, ssZorro is smaller in size, easier to design and more efficient than conventional 2-ON Zorro in inducing DSI. Analysis of the chemical composition of the linker suggests that it could be of importance for future therapeutic considerations.  相似文献   
132.
A series of potent indolyl azetidine rMCHR1 antagonists were found to show poor CNS penetration due to Pgp efflux. We envisioned a strategy which included: lowering basicity; changing the conformational flexibility motif; and removal of a hydrogen bond donor, in an attempt to optimize this property while maintaining target receptor efficacy. This work resulted in mitigation of Pgp efflux, and led us to identify 1-dihydroindolyl azetidine derivatives with CNS penetration and excellent rMCHR1 binding affinity.  相似文献   
133.
Transient receptor potential canonical 5 (TRPC5) forms cationic channels that are polymodal sensors of factors including oxidized phospholipids, hydrogen peroxide, and reduced thioredoxin. The aim of this study was to expand knowledge of the chemical-sensing capabilities of TRPC5 by investigating dietary antioxidants. Human TRPC5 channels were expressed in HEK 293 cells and studied by patch clamp and intracellular Ca(2+) recording. GFP- and HA-tagged channels were used to quantify plasma membrane localization. Gallic acid and vitamin C suppressed TRPC5 activity if it was evoked by exogenous hydrogen peroxide or lanthanide ions but not by lysophosphatidylcholine or carbachol. Catalase mimicked the effects, suggesting that lanthanide-evoked activity depended on endogenous hydrogen peroxide. Trans-resveratrol, by contrast, inhibited all modes of TRPC5, and its effect was additive with that of vitamin C, suggesting antioxidant-independent action. The IC(50) was ~10 μM. Diethylstilbestrol, a related hydroxylated stilbene, inhibited TRPC5 with a similar IC(50), but its action contrasted sharply with that of resveratrol in outside-out membrane patches where diethylstilbestrol caused strong and reversible inhibition and resveratrol had no effect, suggesting indirect modulation by resveratrol. Resveratrol did not affect channel surface density, but its effect was calcium-sensitive, indicating an action via a calcium-dependent intermediate. The data suggest previously unrecognized chemical-sensing properties of TRPC5 through multiple mechanisms: (i) inhibition by scavengers of reactive oxygen species because a mode of TRPC5 activity depends on endogenous hydrogen peroxide; (ii) direct channel blockade by diethylstilbestrol; and (iii) indirect, antioxidant-independent inhibition by resveratrol.  相似文献   
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Neurochemical Research - Pesticides are widely used in agriculture to kill pests, but their action is non-selective and results in several hazardous effects on humans and animals. Pesticide...  相似文献   
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Molecular Biology Reports - Transgenic plants are becoming a more powerful tool in modern biotechnology. Genetic engineering was used in biotech-derived products to create genetically modified (GM)...  相似文献   
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Russian Journal of Bioorganic Chemistry - The biological uses of 2,7-naphthyridines have sparked great attention in recent years. For this reason, we synthesized a series of novel...  相似文献   
139.
Circular RNAs (circRNAs) are a newly validated type of noncoding RNAs recently found to be deregulated in several human cancers. More accurate and specific noninvasive biomarkers are strongly needed for better diagnosis and prognosis of hepatocellular carcinoma (HCC). We performed a bioinformatics analysis to retrieve a novel panel of circRNAs potentially relevant to HCC. We examined their expression in the sera of 68 patients with HCC, 60 patients with chronic hepatitis C, and 36 healthy controls using quantitative polymerase chain reaction. We examined the performance characteristics of the selected circRNA biomarker panel in comparison with alpha-fetoprotein (AFP). In addition, we performed a survival analysis to correlate between their expression levels and patient survival. The circRNAs hsa_circ _00224 and hsa_circ _00520 showed a strong biomarker potential with relatively high sensitivities and specificities compared with AFP. The combined panel including the three circRNAs showed superior performance characteristics relative to those of AFP. The median follow-up period was 26 months. hsa_circ_00520 expression has been shown to be associated with relapse-free survival (P < 0.005). circRNAs hsa_circ_00156, hsa_circ_000224, and hsa_circ_000520 are novel potential biomarkers of high sensitivity and specificity, which could potentially be used in the diagnosis of HCC.  相似文献   
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