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481.
Khan AS Mujer CV Alefantis TG Connolly JP Mayr UB Walcher P Lubitz W Delvecchio VG 《Journal of chemical information and modeling》2006,46(1):111-115
The potential devastation resulting from an intentional outbreak caused by biological warfare agents such as Brucella abortus and Bacillus anthracis underscores the need for next generation vaccines. Proteomics, genomics, and systems biology approaches coupled with the bacterial ghost (BG) vaccine delivery strategy offer an ideal approach for developing safer, cost-effective, and efficacious vaccines for human use in a relatively rapid time frame. Critical to any subunit vaccine development strategy is the identification of a pathogen's proteins with the greatest potential of eliciting a protective immune response. These proteins are collectively referred to as the pathogen's immunome. Proteomics provides high-resolution identification of these immunogenic proteins using standard proteomic technologies, Western blots probed with antisera from infected patients, and the pathogen's sequenced and annotated genome. Selected immunoreactive proteins can be then cloned and expressed in nonpathogenic Gram-negative bacteria. Subsequently, a temperature shift or chemical induction process is initiated to induce expression of the PhiX174 E-lysis gene, whose protein product forms an E tunnel between the inner and outer membrane of the bacteria, expelling all intracellular contents. The BG vaccine system is a proven strategy developed for many different pathogens and tested in a complete array of animal models. The BG vaccine system also has great potential for producing multiagent vaccines for protection to multiple species in a single formulation. 相似文献
482.
A series of novel platinum(II) complexes of diethyl (8-dqmp) and monoethyl (8-Hmqmp) ester of 8-quinolylmethylphosphonic acid has been prepared and studied. It was shown that molecular or ionic complexes could be isolated by reaction of these organophosphorus ligands with [PtX4]2− (X = Cl, Br), depending on the acidity of the reaction solution. In the neutral medium diester formed dihalide adducts, trans-[Pt(8-dqmp)2X2] (1 and 2), with N-bonded ligand through the quinoline nitrogen. Under acidic conditions (pH < 3) both ligands gave the quinolinium salt complexes [LH]2[PtX4] (3 and 4, L = 8-dqmp; 7 and 8, L = 8-Hmqmp), with protonated quinoline ligand as cation and tetrahalidoplatinate complex as anion. By heating in methanol complexes 3 and 4 were converted into the corresponding dimeric hexahalidodiplatinum complexes, [8-Hdqmp]2[Pt2X6] (5 and 6). The chelate complex [Pt(8-mqmp)2] (9), with monoester ligand bonded through the quinoline nitrogen and the deprotonated phosphonic acid oxygen and forming two seven-membered {N, O} chelate rings, was obtained in neutral and basic media by reaction of platinum(II) halides either with sodium or hydrochloride salt of this monoester. The complexes were identified and characterized by elemental and thermogravimetric analyses, conductometric measurements, and by spectroscopic studies. In vitro antitumour activity of complexes was evaluated against the human epidermoid KB and murine leukaemia L1210 cell lines. These results were compared with those obtained for the palladium(II) complexes of the same phosphonate ligands and with those of platinum(II) and palladium(II) complexes of diethyl and monoethyl 2-quinolylmethylphosphonate, in order to correlate the structural and biological properties of quinoline-based aminophosphonate compounds. 相似文献
483.
Beatriz Martín-García María del Carmen Razola-Díaz Ana María Gmez-Caravaca Guillermo Benítez Vito Verardo 《Molecules (Basel, Switzerland)》2021,26(15)
Hawthorn leaves are a rich source of phenolic compounds that possess beneficial activities for human health. Ultrasonic-assisted extraction (UAE) is an extraction technique frequently used for the isolation of phenolic compounds in plants. Thus, in this study, a Box–Behnken design was used to optimize UAE conditions such as the percentage of acetone, the extraction time and solvent-to-solid ratio (v/w) in order to obtain the maximum content of total compounds by Folin–Ciocalteu and the maximum in vitro antioxidant activity by DPPH, ABTS and FRAP assays in Crataegus monogyna leaves. The optimum conditions to obtain the highest total phenolic content and antioxidant activities were 50% acetone, 55 min and 1/1000 (w/v). A total of 30 phenolic compounds were identified and quantified in C. monogyna leaf extract obtained at these optimum UAE conditions. HPLC-MS allows the identification and quantification of 19 phenolic compounds and NP-HPLC-FLD analyses showed the presence of 11 proanthocyanidins. According to the results, the most concentrated phenolic compounds in C. monogyna leaf extract obtained at optimum UAE conditions were phenolic acid derivatives such as protocatechuic acid-glucoside, dihydroxy benzoic acid pentoside and chlorogenic acid, flavones such as 2″-O-rhamnosyl-C-hexosyl-apigenin, flavonols such as hyperoside and isoquercetin and proanthocyanidins such as monomer and dimer. As a result, the optimized UAE conditions could be used to obtain an extract of C. monogyna leaves enriched with phenolic compounds. 相似文献
484.
Vito Lampret 《Central European Journal of Mathematics》2012,10(2):775-787
An asymptotic approximation of Wallis’ sequence W(n) = Π
k=1
n
4k
2/(4k
2 − 1) obtained on the base of Stirling’s factorial formula is presented. As a consequence, several accurate new estimates
of Wallis’ ratios w(n) = Π
k=1
n
(2k−1)/(2k) are given. Also, an asymptotic approximation of π in terms of Wallis’ sequence W(n) is obtained, together with several double inequalities such as, for example,
W(n) ·(an + bn ) < p < W(n) ·(an + b¢n )W(n) \cdot (a_n + b_n ) < \pi < W(n) \cdot (a_n + b'_n ) 相似文献
485.
Vito Napolitano 《Rendiconti del Circolo Matematico di Palermo》2001,50(3):443-454
A well known result on finite linear spaces due to de Bruijn and Erdös states that the numberb of lines is greater than or equal to the numberv of points, withb=v if and only if the linear space is either a near pencil, or a projective plane. The problem of characterizing finite linear spaces with small deficienciess=b?v has been investigated by several authors, especially by Bridges forb=v+1 and de Witte forb=v+2. In this paper we give a unified and short proof for the above mentioned classical results. 相似文献
486.
Paolo Aniello Gianni Cassinelli Ernesto De Vito Alberto Levrero 《Journal of Fourier Analysis and Applications》2001,7(2):199-206
For groups which are the semidirect product of some vector group with a unimodular group we prove that the existence of a
discrete frame obtained from an at-most countable set of vectors through the action of a given unitary representation implies
that the representation in use has to be square-integrable. 相似文献
487.
In this study an analysis of the changes that occur in the infared spectrum of the ethylene–carbon monoxide alternating copolymer as a function of the temperature is presented. This copolymer can assume two polymorphic crystalline states, named POK-α and POK-β. Fourier transform infrared spectroscopy seems to be a good technique to observe the transition between these two forms, which occurs between 120 and 140°C in an undrawn sample. The IR results have been supported by differential scanning calorimetry measurements. The data obtained have, also, clarified that in the solid state the structure of the ethylene–carbon monoxide copolymer is extended by strong intermolecular interactions that weaken its intrinsic resistance and aid its thermal degradation. These interactions are absent or at least less strong in the melt or in the amorphous state. © 1997 John Wiley & Sons, Ltd. 相似文献
488.
Poly[(oligoethylene oxide) ethoxysilane)] ( I ) and poly[(oligoethylene oxide) ethoxysilane)]/(EuCl3)0.67 ( II ) were synthesized by reacting tetraethoxysilane with oligo(ethylene glycol) of molecular weight 400 and oligo(ethylene glycol)400/(EuCl3)0.317, respectively. The products so obtained are very transparent and rubbery. By Fourier transform infrared and Raman spectroscopy studies and by using analytical results it was concluded that these products are crosslinked macromolecular materials where the Si atom is bonded to one OEt group and to three poly(ethylene oxide) 400 chains. Scanning electronic microscopy studies showed that the presence of EuCl3 in polymer host significantly affects the morphology of the material. Laser luminescence investigations on (II) showed that Eu3+ ion in the polymer host is accommodated in two different types of sites having a distorted C2v symmetry. Moreover, the ionic conductivity of these systems was investigated and the data were satisfactorily fitted by the empirical Vogel Tamman Fulcher equation. At 70°C the conductivities of ( I ) and ( II ) were 9 × 10−6 and 14.3 × 10−6 Ω−1 cm−1 respectively. 相似文献
489.
490.
Gregor Trimmel Bogdan Moraru Silvia Gross Vito Di Noto Ulrich Schubert 《Macromolecular Symposia》2001,175(1):357-366
Radical polymerization of methyl methacrylate with 0.5‐2 mol% of the (meth)acrylate‐substituted oxozirconium and oxotitanium clusters Zr6(OH)4O4(OMc)12 (OMc = methacrylate), Zr4O2(OMc)12, Ti6O4(OEt)8(OMc)8 and Ti4O2(OPri)6(OAcr)6 (OAcr = acrylate) results in an efficient cross‐linking of the organic polymers. The obtained inorganic‐organic hybrid polymers exhibit a higher thermal stability due to inhibited depolymerization reactions. Contrary to undoped poly(methyl methacrylate), the cluster cross‐linked polymers are insoluble but swell in organic solvents. The solvent uptake upon swelling decreases with an increasing amount of polymerized cluster. The impedance spectra of PMMA doped with various proportions of Zr4O2(OMc)12 show that the capacitance of the polymers decreases with an increasing proportion of the cluster. The polymer doped with 2 mol% of Zr4O2(OMc)12 shows an increase in conductivity to 0.9·10−7 S·cm−1 at 74°C. 相似文献
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