205 research outputs found
Antitumor effect of therapeutic HPV DNA vaccines with chitosan-based nanodelivery systems
Cervical cancer is the second-most-common cause of malignancies in women worldwide, and the oncogenic activity of the human papilloma virus types (HPV) E7 protein has a crucial role in anogenital tumors. In this study, we have designed a therapeutic vaccine based on chitosan nanodelivery systems to deliver HPV-16 E7 DNA vaccine, considered as a tumor specific antigen for immunotherapy of HPV-associated cervical cancer. We have developed a Nano-chitosan (NCS) as a carrier system for intramuscular administration using a recombinant DNA vaccine expressing HPV-16 E7 (NCS-DNA E7 vaccine). NCS were characterized in vitro for their gene transfection ability. Results: The transfection of CS-pEGFP NPs was efficient in CHO cells and the expression of green fluorescent proteins was well observed. In addition, NCS-DNA E7 vaccine induced the strongest E7-specific CD8+ T cell and interferon γ responses in C57BL/6 mice. Mice vaccinated with NCS-DNA E7 vaccine were able to generate potent protective and therapeutic antitumor effects against challenge with E7-expressing tumor cell line, TC-1. Conclusions: The strong therapeutic effect induced by the Chitosan-based nanodelivery suggest that nanoparticles may be an efficient carrier to improve the immunogenicity of DNA vaccination upon intramuscular administration and the platform could be further exploited as a potential cancer vaccine candidate in humans. © 2014 Tahamtan et al
A qualitative study on personal information management (PIM) in clinical and basic sciences faculty members of a medical university in Iran
Background: Personal Information Management (PIM) refers to the tools and activities to save and retrieve personal information for future uses. This study examined the PIM activities of faculty members of Iran University of Medical Sciences (IUMS) regarding their preferred PIM tools and four aspects of acquiring, organizing, storing and retrieving personal information. Methods: The qualitative design was based on phenomenology approach and we carried out 37 interviews with clinical and basic sciences faculty members of IUMS in 2014. The participants were selected using a random sampling method. All interviews were recorded by a digital voice recorder, and then transcribed, codified and finally analyzed using NVivo 8 software. Results: The use of PIM electronic tools (e-tools) was below expectation among the studied sample and just 37 had reasonable knowledge of PIM e-tools such as, external hard drivers, flash memories etc. However, all participants used both paper and electronic devices to store and access information. Internal mass memories (in Laptops) and flash memories were the most used e-tools to save information. Most participants used "subject" (41.00) and "file name" (33.7 ) to save, organize and retrieve their stored information. Most users preferred paper-based rather than electronic tools to keep their personal information. Conclusion: Faculty members had little knowledge about PIM techniques and tools. Those who organized personal information could easier retrieve the stored information for future uses. Enhancing familiarity with PIM tools and training courses of PIM tools and techniques are suggested
Chitosan nanoparticles as a potential nonviral gene delivery for HPV-16 E7 into mammalian cells
Chitosan nanoparticles (CS NPs) were prepared as a carrier for Human papillomavirus type 16 HPV-16) E7 gene and their gene transfection ability were evaluated in vitro . The plasmid expressing green fl uorescent protein (pEGFP) was used as a reporter gene. Gel electrophoresis demonstrated full binding of CS NPs with the pDNA. The transfection of CS-pEGFP NPs was effi cient in CHO cells and the expression of green fl uorescent proteins was well observed. The expression of E7 proteins was confi rmed under SDS-PAGE and western blot analysis. As a conclusion CS NPs may serve as an eff ective nonviral carrier for delivery of nucleotides into eukaryotic cells. Copyright © 2014 Informa Healthcare USA, Inc
Opioids and viral infections: A double-edged sword
Opioids and their receptors have received remarkable attention because they have the ability to alter immune function, which affects disease progression. In vitro and in vivo findings as well as observations in humans indicate that opioids and their receptors positively or negatively affect viral replication and virus-mediated pathology. The present study reviews recent insights in the role of opioids and their receptors in viral infections and discusses possible therapeutic opportunities. This review supports the emerging concept that opioids and their receptors have both favorable and unfavorable effects on viral disease, depending on the type of virus. Targeting of the opioid system is a potential option for developing effective therapies; however caution is required in relation to the beneficial functions of opioid systems. © 2016 Tahamtan, Tavakoli-Yaraki, Mokhtari-Azad, Teymoori-Rad, Bont, Shokri and Salimi
Stable Magnetic Universes Revisited
A regular class of static, cylindrically symmetric pure magnetic field
metrics is rederived in a different metric ansatz in all dimensions. Radial,
time dependent perturbations show that for dimensions d>3 such spacetimes are
stable at both near r\approx0 and large radius r\rightarrow\infty. In a
different gauge these stability analysis and similar results were known
beforehand. For d=3, however, simultaneous stability requirement at both, near
and far radial distances can not be reconciled for time - dependent
perturbations. Restricted, numerical geodesics for neutral particles reveal a
confinement around the center in the polar plane. Charged, time-like geodesics
for d=4 on the other hand are shown numerically to run toward infinity.Comment: 11 pages, 3figure
Quantum singularities in a model of f(R) Gravity
The formation of a naked singularity in a model of f(R) gravity having as
source a linear electromagnetic field is considered in view of quantum
mechanics. Quantum test fields obeying the Klein-Gordon, Dirac and Maxwell
equations are used to probe the classical timelike naked singularity developed
at r=0. We prove that the spatial derivative operator of the fields fails to be
essentially self-adjoint. As a result, the classical timelike naked singularity
remains quantum mechanically singular when it is probed with quantum fields
having different spin structures.Comment: 12 pages, final version. Accepted for publication in EPJ
Solutions for f(R) gravity coupled with electromagnetic field
In the presence of external, linear / nonlinear electromagnetic fields we
integrate f(R) \sim R+2{\alpha}\surd(R+const.) gravity equations. In contrast
to their Einsteinian cousins the obtained black holes are non-asymptotically
flat with a deficit angle. In proper limits we obtain from our general solution
the global monopole solution in f(R) gravity. The scale symmetry breaking term
adopted as the nonlinear electromagnetic source adjusts the sign of the mass of
the resulting black hole to be physical.Comment: 7 pages no figure, final version for publication in European Physical
Journal
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