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191.
192.
Rosada RS Silva CL Santana MH Nakaie CR de la Torre LG 《Journal of colloid and interface science》2012,373(1):102-109
We report the effects of a synthetic peptide designed to act as a nuclear localization signal on the treatment of tuberculosis. The peptide contains 21 amino acid residues with the following specific domains: nuclear localization signal from SV 40T, cationic shuttle sequence, and cysteamide group at the C-terminus. The peptide was complexed with the plasmid DNAhsp65 and incorporated into cationic liposomes, forming a pseudo-ternary complex. The same cationic liposomes, composed of egg chicken L-α-phosphatidylcholine, 1,2-dioleoyl-3-trimethylammonium-propane, and 1,2-dioleoyl-3-trimethylammonium-propane (2:1:1M), were previously evaluated as a gene carrier for tuberculosis immunization protocols with DNAhsp65. The pseudo-ternary complex presented a controlled size (250 nm), spherical-like shape, and various lamellae in liposomes as evaluated by transmission electron microscopy. An assay of fluorescence probe accessibility confirmed insertion of the peptide/DNA into the liposome structure. Peptide addition conferred no cytotoxicity in vitro, and similar therapeutic effects against tuberculosis were seen with four times less DNA compared with naked DNA treatment. Taken together, the results indicate that the pseudo-ternary complex is a promising gene vaccine for tuberculosis treatment. This work contributes to the development of multifunctional nanostructures in the search for strategies for in vivo DNA delivery. 相似文献
193.
Audrey Alesandra Stinghen Garcia Lonni Renata Longhini Gisely Cristiny Lopes João Carlos Palazzo de Mello Ieda Spacino Scarminio 《Analytica chimica acta》2012
Statistical design mixtures of water, methanol, acetone and ethanol were used to extract material from Trichilia catigua (Meliaceae) barks to study the effects of different solvents and their mixtures on its yield, total polyphenol content and antioxidant activity. The experimental results and their response surface models showed that quaternary mixtures with approximately equal proportions of all four solvents provided the highest yields, total polyphenol contents and antioxidant activities of the crude extracts followed by ternary design mixtures. Principal component and hierarchical clustering analysis of the HPLC–DAD spectra of the chromatographic peaks of 1:1:1:1 water–methanol–acetone–ethanol mixture extracts indicate the presence of cinchonains, gallic acid derivatives, natural polyphenols, flavanoids, catechins, and epicatechins. 相似文献
194.
Roseany V. V. Lopes Luis F. B. Osorio Maria L. Santos Maria J. A. Sales 《Macromolecular Symposia》2012,319(1):173-178
Summary: Given the demand for renewable resources by industries and the promising potential of vegetable oils for this purpose, the current study aims to evaluate the properties of polyurethanes (PUs) obtained from linseed (Linum usitatissimun L.) oil (PULO) and passion fruit (Passiflora edulis Sims f. flavicarpa Degener) oil (PUPFO), by thermogravimetry (TG), derivative thermogravimetry (DTG), dynamic mechanical analysis (DMA) and Fourier transform infrared (FT-IR). The results showed that PULO is more thermally stable than PUPFO, suggesting that the first presents more urethane linkages. The DMA analysis showed that both prepared PUs have uneven porosity, causing the loss of the elastic plateau. It was found as well that PUPFO exhibits a higher value of glass transition temperature (Tg), signifying that it seems to be more crosslinked than PULO. The analysis by FT-IR showed that the curing reaction of PUs was successful. 相似文献
195.
Ricardo Vessecchi Flávio S. Emery Sérgio E. Galembeck Norberto P. Lopes 《Journal of mass spectrometry : JMS》2012,47(12):1648-1659
In order to understand the influence of alkyl side chains on the gas‐phase reactivity of 1,4‐naphthoquinone derivatives, some 2‐hydroxy‐1,4‐naphthoquinone derivatives have been prepared and studied by electrospray ionization tandem mass spectrometry in combination with computational quantum chemistry calculations. Protonation and deprotonation sites were suggested on the basis of gas‐phase basicity, proton affinity, gas‐phase acidity (ΔGacid), atomic charges and frontier orbital analyses. The nature of the intramolecular interaction as well as of the hydrogen bond in the systems was investigated by the atoms‐in‐molecules theory and the natural bond orbital analysis. The results were compared with data published for lapachol (2‐hydroxy‐3‐(3‐methyl‐2‐butenyl)‐1,4‐naphthoquinone). For the protonated molecules, water elimination was verified to occur at lower proportion when compared with side chain elimination, as evidenced in earlier studies on lapachol. The side chain at position C(3) was found to play important roles in the fragmentation mechanisms of these compounds. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
196.
David G. Parker 《中国颗粒学报》2009,7(2)
This paper describes the operation and outcome of one of the United Kingdom's largest multi-partner research activities in nanoparticles.The research covers the discovery and development of organic and inorganic crystals/nanoparticles,nanoparticle properties towards specific product applications,The research also encompassed bespoke measurement technology for nanoparticles and structure interactions.Significant research outcomes are summarised.The paper illustrates the advantages from industrially motivated research and value of collective action between a broad group of researchers in a nation. 相似文献
197.
Irradiated A-type carbonated apatites with carbonate content ranging from 1.45% to 4.84% are studied by using electron paramagnetic resonance (EPR). The EPR spectra are mainly constituted of lines associated to axial CO2− species (g=2.0028 and g=1.9973) and orthorhombic CO3− species (g1=2.0170, g2=2.0090 and g3=2.0041). The production of CO2− species on gamma irradiation depends on the carbonate concentration and the hydroxyapatite stoichiometry. The lowest dose detection limit was achieved with stoichiometric samples and carbonate concentration of 3.7%. 相似文献
198.
In this research work, we deal with the stabilization of uncertain fractional-order neutral systems with delayed input. To tackle this problem, the guaranteed cost control method is considered. The purpose is to design a proportional–differential output feedback controller to obtain a satisfactory performance. The stability of the overall system is described in terms of matrix inequalities, and the corresponding analysis is performed in the perspective of Lyapunov’s theory. Two application examples verify the analytic findings. 相似文献
199.
就像古代神话“特洛伊木马”所描述的,木马攻击是一种策略,它秘密潜入到受安全保护的空间。按照光学量子密钥分发(QKD)协议的说明,这种攻击涉及“木马光子”潜入到光学量子密钥分发系统,企图获取密钥。此前,一类无需外部供电便能工作的被动式光学元件,一直被建议作为一种阻止木马入侵的手段。但是,研究人员至今缺乏一种量化的方法,用以评估这样的被动防御系统的有效性。现在,来自东芝研究-欧洲有限公司(英国)的Andrew Shields 和同事们,已经设计出了一个定量评估方法:借助于量子信息泄漏问题,监察木马攻击。 相似文献
200.
Teixeira Luiz Flávio Lopes Mazzilli Barbara Paci 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(3):551-560
Journal of Radioanalytical and Nuclear Chemistry - The Cananéia-Iguape system is a complex of lagoon and estuarine channels located in the south of state of São Paulo. This system... 相似文献