321 research outputs found
Immunogenicity and protective efficacy of the recombinant Pasteurella lipoprotein E and outer membrane protein H from Pasteurella multocida A:3 in mice
Cataloged from PDF version of article.Pasteurella multocida serotype A:3 is a Gram-negative bacterial pathogen, one of the causative agents of shipping fever of cattle. In this study, outer membrane protein H (ompH) and Pasteurella lipoprotein E (plpE) genes were cloned and plpEC-ompH fusion was constructed and expressed in Escherichia coli. Recombinant PlpE, OmpH and PlpEC-OmpH fusion proteins were purified and formulated with oil-based and oil-based CpG ODN adjuvants. Antibody responses in mice vaccinated with recombinant PlpE and PlpEC-OmpH proteins formulated with both adjuvants were significantly (p<0.05) increased. However, a significant (p<0.05) increment in serum IFN-γ level was only observed upon immunization with oil-based CpG formulations. Protectivity of the vaccines were evaluated via intraperitoneal challenge of mice with 10 LD50 of P. multocida A:3. The recombinant proteins PlpE and PlpEC-OmpH fusion conferred 100% protection when formulated with oil-based CpG ODN while the protectivity was found to be 80% and 60%, respectively when only oil-based adjuvant was used in respective formulations. These findings indicated that the recombinant PlpE or PlpEC-OmpH fusion proteins formulated with oil-based CpG ODN adjuvant are possible acellular vaccine candidates against shipping fever. © 2012 Elsevier Ltd
The Effect of Sources on the Inner Horizon of Black Holes
Single pulse of null dust and colliding null dusts both transform a regular
horizon into a space-like singularity in the space of colliding waves. The
local isometry between such space-times and black holes extrapolates these
results to the realm of black holes. However, inclusion of particular scalar
fields instead of null dusts creates null singularities rather than space-like
ones on the inner horizons of black holes.Comment: Final version to appear in PR
Fuel-cell performance of multiply-crosslinked polymer electrolyte membranes prepared by two-step radiation technique
A multiply-crosslinked polymer electrolyte membrane was
prepared by the radiation-induced co-grafting of styrene and a
bis(vinyl phenyl)ethane (BVPE) crosslinker into a
radiation-crosslinked polytetrafluoroethylene (cPTFE) film. We
then investigated its H2/O2 fuel-cell performance at 60 and 80ºC in
terms of the effect of radiation and chemical crosslinking. At 60ºC,
all the membranes initially exhibited similar performance, but only
the cPTFE-based membranes were durable at 80ºC, indicating the
necessity of radiation crosslinking in the PTFE main chains.
Importantly, cell performance of the multiply-crosslinked
membrane was found high enough to reach that of a Nafion112
membrane. This is probably because the BVPE crosslinks in the
graft component improved the membrane-electrode interface in
addition to membrane durability. After severe OCV hold tests at 80
and 95ºC, the performance deteriorated, while no significant
change was observed in ohmic resistivity. Accordingly, our
membranes seemed so chemically stable that an influence on
overall performance loss could be negligible
Camera, handlens, and microscope optical system for imaging and coupled optical spectroscopy
An optical system comprising two lens cells, each lens cell comprising multiple lens elements, to provide imaging over a very wide image distance and within a wide range of magnification by changing the distance between the two lens cells. An embodiment also provides scannable laser spectroscopic measurements within the field-of-view of the instrument
Renormalization of the charged scalar field in curved space
The DeWitt-Schwinger proper time point-splitting procedure is applied to a
massive complex scalar field with arbitrary curvature coupling interacting with
a classical electromagnetic field in a general curved spacetime. The scalar
field current is found to have a linear divergence. The presence of the
external background gauge field is found to modify the stress-energy tensor
results of Christensen for the neutral scalar field by adding terms of the form
to the logarithmic counterterms. These results are shown to be
expected from an analysis of the degree of divergence of scalar quantum
electrodynamics.Comment: 24 pages REVTe
Camera, handlens, and microscope optical system for imaging and coupled optical spectroscopy
An optical system comprising two lens cells, each lens cell comprising multiple lens elements, to provide imaging over a very wide image distance and within a wide range of magnification by changing the distance between the two lens cells. An embodiment also provides scannable laser spectroscopic measurements within the field-of-view of the instrument
Immunostimulatory activity of polysaccharide-poly(I:C) nanoparticles
Cataloged from PDF version of article.Immunostimulatory properties of mushroom derived polysaccharides (PS) as stand-alone agents were tested. Next. PS were nanocomplexed with polyI:C (pIC) to yield stable nanoparticles around 200 nm in size evidenced by atomic force microscopy and dynamic light scattering analyses. PSs were selectively engaged by cells expressing TLR2 and initiated NF kappa B dependent signaling cascade leading to a Th1-biased cytokine/chemokine secretion in addition to bactericidal nitric oxide (NO) production from macrophages. Moreover, cells treated with nanoparticles led to synergistic IL6, production and upregulation of TNF alpha, MIP3 alpha, IFN gamma and IP10 transcript expression. In mice, PS-Ovalbumin-pIC formulation surpassed anti-OVA IgG responses when compared to either PS-OVA or pIC-OVA mediated immunity. Our results revealed that signal transduction initiated both by TLR2 and TLR3 via co-delivery of pIC by PS in nanoparticle depot delivery system is an effective immunization strategy. The present work implicate that the PS and nucleic acid based nanoparticle approach along with protein antigens can be harnessed to prevent infectious diseases. (C) 2011 Elsevier Ltd. All rights reserve
Effect of suppressive DNA on CpG-induced immune activation.
Bacterial DNA and synthetic oligodeoxynucleotides (ODN) containing unmethylated CpG motifs stimulate a strong innate immune response. This stimulation can be abrogated by either removing the CpG DNA or adding inhibitory/suppressive motifs. Suppression is dominant over stimulation and is specific for CpG-induced immune responses (having no effect on LPS- or Con A-induced activation). Individual cells noncompetitively internalize both stimulatory and suppressive ODN. Studies using ODN composed of both stimulatory and suppressive motifs indicate that sequence recognition proceeds in a 5'-->3' direction, and that a 5' motif can block recognition of immediately 3' sequences. These findings contribute to our understanding of the immunomodulatory activity of DNA-based products and the rules that govern immune recognition of stimulatory and suppressive motifs
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