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61.
In the past two decades a large initiative has been put forth to understand the biological and pathogenic properties of the human T-cell lymphotropic virus type 1 (HTLV-1); this has ultimately led to the development of various experimental vaccination and therapeutic strategies to combat HTLV-1 infection. The focus of this work is to outline key targets for the design of therapeutics for HTLV-1, such as fusion mediated by the envelope glycoprotein, and to discuss reports of novel vaccines or therapeutics. These strategies include peptide, recombinant protein, DNA, and viral vectors. The final focus of this review is to acquaint the reader with vaccine approaches developed in our laboratory over the last decade. These strategies include the development of envelope glycoprotein derived B-cell epitopes for the induction of neutralizing antibodies, as well as a strategy to generate a multivalent cytotoxic T-lymphocyte (CTL) response against the HTLV-1 Tax antigen. 相似文献
62.
We demonstrate, analytically and experimentally, a simple, but effective method to determine the topological charge of an optical vortex by using a spherical bi-convex lens, a ubiquitous optical element found in any optics laboratory. Just by tilting the lens and recording the intensity distribution of a propagating vortex at a predicted position past the lens, we have been able to measure both the sign and the magnitude of the topological charge m up to m=±14. Our experimental results are in excellent agreement with analytical predictions. 相似文献
63.
The electrical resistivity of compounds having compositions LaSr2Nb x ,O y LaSrNb x O y , and La2SrNb x O y , prepared by arc melting under argon atmosphere, is determined from 77 to 300 K. Low resistivity compositions are found in these systems for x > 2 and niobium in divalent state. None of the compounds investigated showed large resistance drop reported by Oguchi et al. (1987) in La-Sr-Cu-O compounds prepared by sputtering La2CuO4 on niobium substrate and attributed to possible superconductivity about 250 K. 相似文献
64.
Aekta Aggarwal Manas Ranjan Sahoo Abhrojyoti Sen Ganesh Vaidya 《Studies in Applied Mathematics》2020,145(2):247-290
Measure-valued weak solutions for conservation laws with discontinuous flux are proposed and explicit formulae have been derived. We propose convergent discontinuous flux-based numerical schemes for the class of hyperbolic systems that admit nonclassical -shocks, by extending the theory of discontinuous flux for nonlinear conservation laws to scalar transport equation with a discontinuous coefficient. The article also discusses the concentration phenomenon of solutions along the line of discontinuity, for scalar transport equations with a discontinuous coefficient. The existence of the solutions for transport equation is shown using the vanishing viscosity approach and the asymptotic behavior of the solutions is also established. The performance of the numerical schemes for both scalar conservation laws and systems to capture the -shocks effectively is displayed through various numerical experiments. 相似文献
65.
The CuSO4/ascorbate-mediated ‘click’ reaction of 2-(2-azidophenyl)-4,5-diaryloxazoles and arylacetylenes proceeded through an alternate pathway whereby reduction of the azide predominated over formation of the 1,2,3-triazole-forming cycloaddition. The unimolecular product, 2-(2-aminophenyl)-4,5-diphenyloxazole, was isolated which appears to be a formal reduction of the arylazide to the corresponding arylamine. A series of oxazoles which possessed various substituents (F, Cl, Br, OCH3) on the 4,5-diaryl rings and having the 2-azido group on the 2-oxazolylphenyl position were submitted to the same ‘click’ conditions and gave the corresponding arylamine products (73–99%). The reaction appears to be specific toward the ortho-azido substitution of the polycyclic system, as the corresponding azidomethyl-substituted phenyl oxazoles do not give the ‘reduction’ products but gave the expected click products with the acetylenic co-reactants. 相似文献
66.
An efficient copper-aluminum hydrotalcite catalyst for asymmetric hydrosilylation of ketones at room temperature 总被引:1,自引:0,他引:1
Kantam ML Laha S Yadav J Likhar PR Sreedhar B Jha S Bhargava S Udayakiran M Jagadeesh B 《Organic letters》2008,10(14):2979-2982
A catalyst system consisting of a copper-aluminum hydrotalcite-chiral diphosphine ligand effects asymmetric hydrosilylation of several ketones, using polymethylhydrosiloxane (PMHS) as the stoichiometric reducing agent at room temperature, with moderate-to-excellent enantioselectivities. The catalyst is recovered by simple centrifugation, and the efficiency of the catalyst remains almost unaltered even after several cycles. 相似文献
67.
Mhaske Harshad P. Vaidya Vikas V. Menon Sasikumar N. Shailajan Sunita Gomes Noel A. 《平面色谱法杂志一现代薄层色谱法》2008,21(3):217-219
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
68.
Noel A. Gomes Ashutosh M. Pudage Santosh S. Joshi Vikas V. Vaidya Sagar A. Parekh 《Chromatographia》2008,68(7-8):541-550
A rapid and sensitive LC–MS–MS method has been developed and validated for simultaneous analysis of abacavir (ABA) and lamivudine (LAM) in human plasma. The analytes were extracted from human plasma by SPE. Nelfinavir (NEL) and emtricitabine (EMT) were used as the internal standards for ABA and LAM, respectively. An RP18 column enabled chromatographic separation of the analytes. The method involves simple isocratic chromatography and MS detection in positive-ionization mode. Validation of the method showed response was a linear function of concentration in the ranges 100.0–7000.0 ng mL?1 for ABA and 80.0–5000.0 ng mL?1 for LAM. At the LOQ levels, inter-run and intra-run precision were within 5.80 and 3.51%, respectively, for ABA and within 4.68 and 3.16%, respectively, for LAM. Overall recovery for ABA and LAM was 59.32 and 105.18%, respectively. Total elution time was 2 min only, which enabled quantification of more than 200 plasma samples per day. This validated method was used successfully for analysis of plasma samples from a bioequivalence study. 相似文献
69.
Pravin Shende Renuka Chaphalkar Kiran Deshmukh R. S. Gaud 《Journal of Dispersion Science and Technology》2016,37(4):504-511
Lansoprazole is a proton-pump inhibitor used in treatment of gastric ulcers, gastroesophageal reflux disease (GERD), and Zollinger–Ellison syndrome. The objective of the study was physicochemical investigation and comparative characterization of nanosuspensions of lansoprazole by complexing with β-cyclodextrin and β-cyclodextrin-based nanosponges to enhance its solubility and stability. Inclusion complexes of lansoprazole with β-cyclodextrin and nanosponges were prepared by physical method and polymer condensation method, respectively. Particle size, zeta potential, encapsulation efficiency, in vitro release, FTIR, and Differential Scanning Calorimeter (DSC) studies were used as characterization parameters. The average particle size of lansoprazole nanoparticles was found to be in the range of 178.7 ± 6.39 nm to 204.9 ± 2.91 nm. The high zeta potential values were attained to ensure a high-energy barrier and favor a good stability of nanosuspensions. In vitro release study showed the controlled release of lansoprazole, which was more satisfactory than individual drug. FTIR spectroscopy showed that there was interaction of cyclodextrin and its nanosponges with drug. DSC study revealed that drug was involved in complexion with cyclodextrin and nanosponges. Solubility and stability of lansoprazole were remarkably improved by inclusion complexation. Based on these findings, it can be concluded that engineered nanosuspension of lansoprazole is a promising carrier for nanoparticulate drug delivery in gastric ulcer. 相似文献
70.