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181.
Cibacron Blue F3GA was immobilized on poly(hydroxyethyl methacrylate) cryogel and it was used for selective and efficient depletion of albumin from human serum. The poly(hydroxyethyl methacrylate) was selected as the basic component because of its inertness, mechanical strength, chemical and biological stability, and biocompatibility. Cibacron Blue F3GA was covalently attached to the poly(hydroxyethyl methacrylate) cryogel to produce poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel affinity column. The poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel was characterized with respect to gelation yield, swelling degree, total volume of macropores, Fourier Transform Infrared spectroscopy, and scanning electron microscopy. It was found that the maximum amount of adsorption (343 mg/g of dry cryogel) obtained from experimental results is very close to the calculated Langmuir adsorption capacity (345 mg/g of dry cryogel). The maximum adsorption capacity for poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel column was obtained as 950 mg/g of dry cryogel for nondiluted serum. The adsorption capacity decreased with increasing dilution ratios while the depletion ratio of albumin remained as 77% in serum sample. Finally, the poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel was optimized for using in the fast protein liquid chromatography system for rapid removal of the high abundant proteins from the human serum. 相似文献
182.
Hybrid agents which combine potent DNA-photocleavers with tunable amino acids or small peptides were designed to improve selectivity of Nature's most potent class of antibiotics towards cancer cells. The ability of these compounds to photocleave DNA is controlled by their incorporation into hybrid architectures with functional elements derived from natural amino acids. These conjugates are highly effective at inducing double-strand DNA cleavage and, in some cases, rival or even surpass both naturally occurring DNA cleavers and anticancer agents that are currently in clinical use. The possibility of triggering their activity in a photochemical and pH-sensitive fashion allows for a high degree of selectivity over activation. The conjugates were shown to penetrate cell membranes and induce efficient intracellular DNA cleavage. Initial in vitro tests against a variety of cancer cell lines confirm the potential of these compounds as anticancer agents at low nanomolar concentrations. 相似文献
183.
Andelman T Gong Y Polking M Yin M Kuskovsky I Neumark G O'Brien S 《The journal of physical chemistry. B》2005,109(30):14314-14318
Nanocrystals of the wide band gap semiconductor zinc oxide of controllable morphologies were synthesized by a simple thermal decomposition method. The predominating factor in determining the morphology (spheres, triangular prisms, and rods) was the solvent, selected on the basis of coordinating power. The nanoparticles were structurally analyzed, and the photoluminescence of each shape was compared. The intensity of the green band emission, common to many ZnO structures, was found to vary with morphology. The strongest green band intensity corresponded to the shape with the largest surface/volume ratio and could be attributed to surface oxygen vacancies. Control over the morphology of ZnO at the nanoscale is presented as a means to control the green band emission. 相似文献
184.
Solid solutions in the system zinc sulfide/zinc phosphide (Zn(2+)(x)S(2-2xP(2x)) were investigated using the cyclic cluster model within the semiempirical MSINDO method. Results of cyclic cluster calculations for binding energies of the perfect ZnS and Zn(3)P(2) are presented and compared with the experimental data. The miscibility of ZnS and Zn(3)P(2) over the whole composition range of 0 < x < 1 was investigated by calculating the Gibbs free energy of mixing Delta(M)G for different values of x. A miscibility gap was found at both ends of the composition range and compared with experimental data. 相似文献
185.
The packing characteristics of process-scale chromatography columns were evaluated using the responses to conductivity-based pulse and step inputs derived from tracer experiments and in-process transitions (i.e. column equilibration and regeneration steps). Characteristics of the measured residence time distributions (RTDs) were quantified by statistical moments and using the equations derived from the Gaussian model. The first and second moments calculated from in-process step transitions for multiple runs were in good agreement with those moments calculated from the pulse-input experiments conducted immediately after column packing. This indicates that most of the time the bed behavior at the time of packing is consistent with that at the time of operation. Due to the significant resistance to protein mass transfer inside the particles, estimated plate heights for protein solutes are expected to be much greater than those observed from the experiments using saltbased tracers. Thus, the column efficiency derived from salt-based experiments can be a useful measure of packing consistency rather than a significant parameter influencing the outcome of protein separations. 相似文献
186.
Joseph Schwager Nicole Seifert Albine Bompard Daniel Raederstorff Igor Bendik 《Molecules (Basel, Switzerland)》2021,26(18)
Vitamins and bioactives, which are constituents of the food chain, modulate T lymphocyte proliferation and differentiation, antibody production, and prevent inflammation and autoimmunity. We investigated the effects of vitamins (vitamin A (VA), D (VD), E (VE)) and bioactives (i.e., resveratrol (Res), epigallocatechin-3-gallate (EGCG)) on the adaptive immune response, as well as their synergistic or antagonistic interactions. Freshly isolated T lymphocytes from healthy individuals were activated with anti-CD3/CD28 antibodies for 4–5 days in the presence of bioactives and were analyzed by cytofluorometry. Interleukins, cytokines, and chemokines were measured by multiple ELISA. Gene expression was measured by quantitative RT-PCR. Res and EGCG increased CD4 surface intensity. EGCG led to an increased proportion of CD8+ lymphocytes. Anti-CD3/CD28 activation induced exuberant secretion of interleukins and cytokines by T lymphocyte subsets. VD strongly enhanced Th2 cytokines (e.g., IL-5, IL-13), whereas Res and EGCG favored secretion of Th1 cytokines (e.g., IL-2, INF-γ). Res and VD mutually influenced cytokine production, but VD dominated the cytokine secretion pattern. The substances changed gene expression of interleukins and cytokines in a similar way as they did secretion. Collectively, VD strongly modulated cytokine and interleukin production and favored Th2 functions. Resveratrol and EGCG promoted the Th1 response. VA and VE had only a marginal effect, but they altered both Th1 and Th2 response. In vivo, bioactives might therefore interact with vitamins and support the outcome and extent of the adaptive immune response. 相似文献
187.
Shestakova Tatyana S. Deev Sergey L. Khalymbadzha Igor А. Rusinov Vladimir L. Paramonov Alexander S. Arseniev Alexander S. Shenkarev Zakhar O. Charushin Valery N. Chupakhin Oleg N. 《Chemistry of Heterocyclic Compounds》2021,57(4):479-482
Chemistry of Heterocyclic Compounds - Isotope-labeled antiviral drug Triazavirin containing 2H, 13C, and 15N atoms in its structure has been synthesized. 13C2H3I and KS13CN served as donors of 13C... 相似文献
188.
Zhanneta R. Gulyaeva Igor I. Patsanovsky Elenora A. Ishmaeva K. Micheal Pietrusiewicz 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract A series of derivatives R1R2P(X)R3, where R1=R2=Ph. R3= -CH=CH-Me, X=O(I); R1=Me, R2=Ph, R3= -CH=CH2, X=O(II); R1=R2=Ph, R3= -CH=CH2, X=Se(III) and R1R2P(O)-CH2C(O)OX, where R1=Ph, R2= -CH=CH2, X=Ment?(IV); R1=Ph-2-OMe, R2=Ph, X=Ment?(V); R1=R2=CH2Ph, X=Et(I), were investigated by means of dipole moments method. The problem of conjugation in phosphorylethylenes and conformation behaviour of phosphorylacetates was considered. DM (exp.) of (I-IV), determined in CC14 solution are 4.48(I), 4.27(II), 4.97(III), 4.21(IV), 5.21(V) and 4.02 D (VI). The intramolecular electronic interactions of phosphoryl group with unsaturated fragment did not displays in polarity properties of compounds (I-III). The experimental dipole moments of derivatives (I-III) are equal to the calculated values of DM. DM (IV-VI) is very sensitive to orientation of the P=O and C=O polar bonds. Because DM (exp.) of these compounds very sensitive to its orientation. DM (calc.) for cis- and trans- orientation of P=O and C=O dipoles are really different, that allows to drow the conclution that, in the contrast to the crystal state, the corresponded dipoles prefer an anti array in solution. 相似文献
189.
Lidiya I. Kursheva Anatoly M. Il'in Elvira S. Batyeva Igor A. Litvinov Olga N. Kataeva Aidar T. Gubaidullin 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract The series of copper (I) complexes with thiophosphite ligands was prepared and examined to determine the factors that affect the coordination mode of the ligand with metal. 相似文献
190.