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121.

Background

A recent human clinical trial of an Alzheimer's disease (AD) vaccine using amyloid beta (Aβ) 1–42 plus QS-21 adjuvant produced some positive results, but was halted due to meningoencephalitis in some participants. The development of a vaccine with mutant Aβ peptides that avoids the use of an adjuvant may result in an effective and safer human vaccine.

Results

All peptides tested showed high antibody responses, were long-lasting, and demonstrated good memory response. Epitope mapping indicated that peptide mutation did not lead to epitope switching. Mutant peptides induced different inflammation responses as evidenced by cytokine profiles. Ig isotyping indicated that adjuvant-free vaccination with peptides drove an adequate Th2 response. All anti-sera from vaccinated mice cross-reacted with human Aβ in APP/PS1 transgenic mouse brain tissue.

Conclusion

Our study demonstrated that an adjuvant-free vaccine with different Aβ peptides can be an effective and safe vaccination approach against AD. This study represents the first report of adjuvant-free vaccines utilizing Aβ peptides carrying diverse mutations in the T-cell epitope. These largely positive results provide encouragement for the future of the development of human vaccinations for AD.  相似文献   
122.
The modifications in electrical and magnetic properties of polycrystalline bulk La0.7Ca0.3Mn1−xTxO3 (T=Fe, Ga) samples at relatively higher doping concentration (x=0.08-0.12) are investigated. All the synthesized, single phase samples were subjected to resistivity measurements in the temperature range 50-300 K. No insulator-metal transition (TP) was observed for Fe doped samples with x=0.12. For all the other samples the transition temperature decreased with increase in doping concentration. The small polaron hoping energy was found to increase, rather slowly, with increase in doping concentration. The effect on magnetic properties is also prominently observed with respect to doping element and doping concentration. Interestingly, with the increase in doping concentration, the Curie temperature (TC) and TP separate out significantly indicating decoupling of electric and magnetic properties. Changes in these properties have been analyzed on the basis of magnetic disorder introduced in the system due to the magnetic and nonmagnetic nature of these ions rather than strong lattice effects which is insignificant due to similar ionic radii of Fe+3 and Ga+3 when compared to that of Mn+3.  相似文献   
123.
The basic representation of A n (1) is constructed on a space of paths in (n + 1). A q-analogue of this is also presented. Our construction gives a Lie theoretical proof of a combinatorial identity used in the evaluation of the local state probabilities for a class of solvable lattice models.  相似文献   
124.
We define the Jaumann derivative of a tensor field in relativity by a formal generalization of a stress rate in viscoelasticity. A tensor field is said to be Jaumann transported iff its Jaumann derivative vanishes. It is found that the gravitational potentials are Jaumann transported identically. The concept of a complete rotation tensor has been introduced to study the Jaumann derivative with respect to a null vector field. This provides a characterization of the integrability of a hypersurface orthogonal congruence. A perfect fluid collapsing by neutrino emission and undergoing Jaumann transport with respect to the neutrino flow is found to be compatible with that of a catastrophic collapse. The circumstances leading to the existence of ghost neutrinos are cited. The degeneracy of the Kerr-Newman black hole into the Reissner-Nordstrom black hole is expressed in terms of the Jaumann propagation.  相似文献   
125.
The magnetic properties of antiferromagnetic compound Mn3B4 were examined using pulsed magnetic field up to 470 kOe. It was found that Mn3B4 shows a clear metamagnetic transition under 360 kOe at 4.2K. The present results are not explained by the magnetic structure proposed by Neov and a modified magnetic structure is proposed to understand the present magnetization curve. The magnetic phase diagram in the H-T plane is shown.  相似文献   
126.
We study the local state probabilities of the vertex models in the face formulation associated with the simple Lie algebras X n =A n, B n, C n, D n. The corner transfer matrix method expresses them in terms of one-dimensional configuration sums. We show that the latter are the string functions of X n (1) modules. We also present similar results for the restricted face models of types B n (1), C n (1), D n (1).  相似文献   
127.
128.
Evidence for the cation-radical of pyridine is obtained by ESR and optical studies of γ-irradiated frozen solutions of pyridine in trichlorofluoromethane at 77 and 4 K. The cation-radical is a σ-type radical, the positive charge residing mostly in the nitrogen lone pair orbital. Consistent spectral data are obtained also for 2-deutero-, 4-deutero-, 2,6-dideutero-, and perdeutero-pyridines.  相似文献   
129.
Lithiation of S-(2-methylphenyl) N,N,N',N'-tetramethylphosphorodiamidothioate with sec-BuLi at -105° gave the corresponding benzylic anion which was acylated with various aromatic esters to give various deoxybenzoin derivatives in moderate to high yields. Acidic treatment of these products in refluxing formic acid gave 2-arylbenzo[b]thiophene derivatives. 2-Methylbenzo[b]thiophene and benzo[b]thiophen-2(3H)-one were also prepared using the similar procedure.  相似文献   
130.
The synthesis of several UO(2)-alaskaphyrin derivatives functionalized with aliphatic chains is described. These compounds are found to be liquid-crystalline and form columnar mesophases, as judged from polarizing optical microscopy studies, and represent the first uranium-containing discotic mesogens.  相似文献   
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