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991.
We used N-methylpyrrole (Py)-N-methylimidazole-(Im) polyamide as an exogenous agent to modulate the formation of DNA assemblies at specific double-stranded sequences. The concept was demonstrated on the hybridization chain reaction that forms linear DNA. Through a series of melting curve analyses, we demonstrated that the binding of Py−Im polyamide positively influenced both the HCR initiation and elongation steps. In particular, Py−Im polyamide was found to drastically stabilize the DNA duplex such that its thermal stability approached that of an equivalent hairpin structure. Also, the polyamide served as an anchor between hairpin pairs in the HCR assembly, thus improving the originally weak interstrand stability. We hope that these proof-of-concept results can inspire future use of Py−Im polyamide as a molecular tool to modulate the formation of DNA assemblies.  相似文献   
992.
The aim of the study is to investigate the biochemical composition of grapeseed oil and cake from an unexplored Indian grape‐juice cultivar, Manjari Medika (MM). The composition of oil and residual seed cake is evaluated using various chromatographic and spectroscopic techniques. The findings demonstrate that the vitamin E content of MM‐seed oil (1.15–1.35 g kg?1) is distinctively higher than the Codex standard, suggesting its superior quality as an edible oil. The predominant triacylglycerols include trilinolein (LLL, 43%), dilinoleoyl‐stearylglycerol (LSL, 19%), and dilinoleoyl‐palmitoylglycerol (LLP, 11%), which are earlier recognized as natural antioxidants. The seed‐cake is rich in polyphenols including acylated anthocyanins (e.g., pelargonidin‐3‐O‐coumaroyl glucoside) and certain other flavonoids (e.g., catechin). The profile of phytonutrients in MM seed‐oil and cake is significantly superior to its seeded female parent and two other widely cultivated wine‐grape varieties. In brief, the studied by‐products of this new grape‐juice cultivar can be an important source of high‐value ingredients for use in food supplements, nutraceuticals, and functional foods. Practical applications: This study reports the phytochemical profile of the seed‐oil and seed cake derived from a newly developed grape variety, Manjari Medika. High contents of selective antioxidants: lipids, vitamin E, and phenols in the seed‐oil and cake with health benefits suggest their potential for use in nutraceutical and functional foods. These byproducts can be utilised as ingredients of functional foods and nutraceuticals (e.g., grape seed oil capsule) and also as raw materials in food supply chains (e.g., for production of grape cookies or cake). MM can also be utilized as a colorant in the food industry.  相似文献   
993.
Proton-detected 100 kHz magic-angle-spinning (MAS) solid-state NMR is an emerging analysis method for proteins with only hundreds of microgram quantities, and thus allows structural investigation of eukaryotic membrane proteins. This is the case for the cell-free synthesized hepatitis C virus (HCV) nonstructural membrane protein 4B (NS4B). We demonstrate NS4B sample optimization using fast reconstitution schemes that enable lipid-environment screening directly by NMR. 2D spectra and relaxation properties guide the choice of the best sample preparation to record 2D 1H-detected 1H,15N and 3D 1H,13C,15N correlation experiments with linewidths and sensitivity suitable to initiate sequential assignments. Amino-acid-selectively labeled NS4B can be readily obtained using cell-free synthesis, opening the door to combinatorial labeling approaches which should enable structural studies.  相似文献   
994.
Russian Engineering Research - On the profilograms obtained for real surfaces machined by different methods, the microprojections resemble elements of sinusoids and cosinusoids. Accordingly, it is...  相似文献   
995.
The present work focuses on the fabrication of βTCP (β-tricalcium phosphate) and HA/βTCP (hydroxyapatite/β-tricalcium phosphate) composite coatings by plasma spraying. The starting powders were produced via solid-state method using 2 wt% MgO to stabilize βTCP phase. The synthesized powders were preliminarily granulated to be used by the plasma spray process. Coatings obtained on titanium substrates are uniform and well adherent but due to the high temperature and cooling rate typical for plasma spraying process, βTCP phase is almost totally transformed into the α allotrope. Thermal treatment at 800 °C allows the reconversion of the phase αTCP→ βTCP. It is therefore possible to produce coatings with tuneable dissolution properties by selecting the proper initial powder mixture and the specific thermal treatment.  相似文献   
996.
Crossover designs are an extremely useful tool to investigators, and group sequential methods have proven highly proficient at improving the efficiency of parallel group trials. Yet, group sequential methods and crossover designs have rarely been paired together. One possible explanation for this could be the absence of a formal proof of how to strongly control the familywise error rate in the case when multiple comparisons will be made. Here, we provide this proof, valid for any number of initial experimental treatments and any number of stages, when results are analyzed using a linear mixed model. We then establish formulae for the expected sample size and expected number of observations of such a trial, given any choice of stopping boundaries. Finally, utilizing the four-treatment, four-period TOMADO trial as an example, we demonstrate that group sequential methods in this setting could have reduced the trials expected number of observations under the global null hypothesis by over 33%.  相似文献   
997.
Carbohydrates and their conjugates play important roles in many biological processes including fertilization, differentiation, development, immune response, and infection. Their activities are largely dependent on the properties of terminal mono‐ or disaccharides. Galactose, mannose, fucose, glucose, sialic acid, etc., are commonly used as powerful scaffolds installed on drug molecules for targeting specific tissues including brain, liver, and cancers, and as epitopes for enhancing the targeting of various vaccines. This review focuses on the influence of their structural variations, including changes in sugar type, substituent groups and their positions, as well as length of linker portion, on the targeting of drugs or their efficacy. Particular attention is paid to the targeting properties of mono‐ and disaccharides applied in drug design and discovery.  相似文献   
998.
999.
Targeting the tumor cell mitochondrion could produce novel anticancer agents. We designed an aryl−urea fatty acid ( 1 g ; 16({[4-chloro-3-(trifluoromethyl)phenyl]carbamoyl}amino)hexadecanoic acid) that disrupted the mitochondrion and decreased MDA-MB-231 breast cancer cell viability. To optimize the aryl−ureas the present study evaluated mitochondrial targeting by 1 g analogues containing alkyl chains between 10–17 carbons. Using the dye JC-1, the C12−C17 analogues efficiently disrupted the mitochondrial membrane potential (IC50s 3.5±1.2 to 7.6±1.1 μM) and impaired ATP production; shorter analogues were less active. 7-Aminoactinomycin D/annexin V staining and flow cytometry showed that these agents activated the killing mechanisms of necrosis and apoptosis to varying extents (7-aminoactinomycin D/annexin V staining ratios 4.3–6.0). Indeed, 1 g and its C17 analogue preferentially activated necrosis and apoptosis, respectively (ratios 2.1 and 16). Taken together, alkyl chain length is a determinant of mitochondrial targeting by aryl−ureas and can be varied to develop analogues that activate apoptosis or necrosis in a regulated fashion.  相似文献   
1000.
The solvent-dependent polymorphism of the active pharmaceutical ingredient (API) carbamazepine is interpreted from calculations of the solid-state and API-solvent intermolecular interactions. These simulations suggested that apolar solute-solute interactions could be disrupted by apolar solvents. In contrast, the polar solute-solute interactions were found to be easily disrupted by polar and protic solvents. This is consistent with experimental observations that the crystallization of the metastable form II is more dominant in apolar solvents. The Mercury program remains the gold standard in terms of usability; however, further expansion into more complex simulation techniques could make this package of even greater use in pharmaceutical manufacturing workflows.  相似文献   
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