194 research outputs found
Expression of an innate immune element (mouse hepcidin-1) in baculovirus expression system and the comparison of its function with synthetic human hepcidin-25
Hepcidin is an innate immune element which decreases the iron absorption from diet and iron releasing from macrophage cell. In contrast to the chemical iron chelators, there has been limited effort applied to the specific use of hepcidin as a new drug for decreasing the iron overload. Hepcidin is produced in different biological systems. For instance, E-coli is used for human hepcidin expression, however, post-translational modification is impaired. We have used a simple baculovirus expression system (BES) to improve the hepcidin folding and activity. Hepcidin Messenger Ribonucleic acid (mRNA) was isolated from mouse liver cells and its complementary Deoxyribonucleic acid (cDNA) was produced and amplified. PFastBac HTB vector was used for recombinant bacmid production. Recombinant baculovirus was produced using SF-9 cell line. The mouse hepcidin-1 protein was expressed in a large quantity and functional tests were performed for this recombinant peptide. The yield of hepcidin in BES was 20 μg/mL and anti-histidine (anti-His) tag antibody was used for the confirmation of hepcidin on western blot nitrocellulose paper. Functional tests showed that mouse hepcidin accumulates iron in the macrophage cell line J774A.1 up to 63%. In addition, our data showed that the mouse hepcidin-1 has less toxicity compared to the synthetic human hepcidin-25 (p = 0.000). © 2011 by School of Pharmacy
Rectal necrosis: A rare complication of palliative radiotherapy for sacral spine metastasis
Radiation proctocolitis is a common side effect of radiation therapy. In rare cases, chronic radiation injury can be severe enough to cause rectal necrosis. In this study, a case of rectal necrosis after sacral spine radiotherapy was presented. Anterior rectal wall necrosis and rectovaginal fistula is thought to be rare, severe and challenging rectal long-term complication of the previous sacral spine irradiation. Although, rectovaginal fistula which resulted in intractable rectal bleeding seems to be a rare side-effect of radiotherapy, physicians must not forget about this complication, as it can be fatal in patients who often have been cured of cancer. © 2018, Journal of Clinical and Diagnostic Research. All rights reserved
Rectal necrosis: A rare complication of palliative radiotherapy for sacral spine metastasis
Radiation proctocolitis is a common side effect of radiation therapy. In rare cases, chronic radiation injury can be severe enough to cause rectal necrosis. In this study, a case of rectal necrosis after sacral spine radiotherapy was presented. Anterior rectal wall necrosis and rectovaginal fistula is thought to be rare, severe and challenging rectal long-term complication of the previous sacral spine irradiation. Although, rectovaginal fistula which resulted in intractable rectal bleeding seems to be a rare side-effect of radiotherapy, physicians must not forget about this complication, as it can be fatal in patients who often have been cured of cancer. © 2018, Journal of Clinical and Diagnostic Research. All rights reserved
Bioinformatic designing for producing vaccine peptide of human vascular endothelial growth factor (VEGF-A), and evaluation of polyclonal antibodies in mice
Background: It is stated that in the absence of angiogenesis, the tumoral tissue will not grow beyond 2 mm3. Vascular endothelial growth factor (VEGF) plays a pivotal role in angiogenesis and blockade of this phenomenon could be applied as a novel strategy for immunotherapy of cancer. Methods: Peptide sequences of VEGF-A isoforms were derived from protein databases and aligned. Immunodominant epitopes were determined and the selected one was rechecked for dissimilarity with other human proteins. The selected conserved peptide sequence was synthesized and conjugated with Keyhole limpet hemocyanin (KLH). Then, it was applied for immunization of mice. The polyclonal anti-VEGF antibody titer was measured using an indirect peptide-enzyme-linked immunosorbent assay (ELISA) with a Bovine serum albumin (BSA)-conjugated peptide. Findings: According to bioinformatic findings, the selected 41-aminoacid sequence did not show any similarity with other human proteins and revealed enough antigenicity to stimulate anti-tumor specific responses. A substantial increase of specific antibody titer was observed in vaccinated mice. Sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE) analysis of the BSA-conjugated peptide showed efficient coupling of the molecules. Optimization steps in ELISA procedures revealed that coating of microtiter plates with BSA-conjugated antigen provided more reproducible outcome than unconjugated peptide. Conclusion: Our results reinforce the potential of KLH-conjugated peptides for immunization and production of specific polyclonal antibodies against VEGF-A. Production of high-titer antibodies against this autoantigen indicates that the designed peptide-vaccine could be used as a potential immunogen for stimulation of humoral immune system in animal model. © 2016, Isfahan University of Medical Sciences(IUMS). All rights reserved
Induction of humoral immune responses and inhibition of metastasis in mice by a VEGF peptide-based vaccine
Objective(s): Blocking of vascular endothelial growth factor (VEGF) plays a pivotal role in inhibition of metastasis and is a target for development of anti-angiogenic agents. In this study, a peptide-based vaccine was designed and its potential for induction of humoral immune responses, generation of neutralizing antibodies, inhibition of tumor growth and metastasis was determined. Materials and Methods: With online bioinformatics tools, a fragment of the VEGF-A was selected for a peptide-based vaccine. To enhance its antigenicity, the peptide was conjugated with Keyhole limpet hemocyanin and used to immunize mice. Then, the polyclonal anti-VEGF antibody titer was measured and its effect on proliferation of HUVEC cell line was investigated by MTT assay. Finally, we checked the effect of the peptide on tumor growth, metastasis, and survival rates in a mouse model of cancer. Results: The bioinformatics analysis of the selected region confirmed dis-similarity of the peptide with any other human protein and its acceptable antigenicity to stimulate a tumor-specific humoral response. Anti-VEGF antibody titers were significantly greater in vaccinated mice than in controls. IgG antibody from mice immunized with recombinant VEGF-A inhibited HUVEC proliferation (P<0.0001). Tumors in vaccinated mice were significantly smaller than those in controls. Moreover, metastasis was reduced and survival rates increased in the vaccinated group. Conclusion: Production of high-titer antibody against the peptide vaccine indicated that the peptide has the potency to be used as a peptide-based vaccine for humoral inhibition of tumor growth and metastasis. The efficacy of the peptide should be further tested in primate models. © 2020 Mashhad University of Medical Sciences. All rights reserved
Gravitating discs around black holes
Fluid discs and tori around black holes are discussed within different
approaches and with the emphasis on the role of disc gravity. First reviewed
are the prospects of investigating the gravitational field of a black
hole--disc system by analytical solutions of stationary, axially symmetric
Einstein's equations. Then, more detailed considerations are focused to middle
and outer parts of extended disc-like configurations where relativistic effects
are small and the Newtonian description is adequate.
Within general relativity, only a static case has been analysed in detail.
Results are often very inspiring, however, simplifying assumptions must be
imposed: ad hoc profiles of the disc density are commonly assumed and the
effects of frame-dragging and completely lacking. Astrophysical discs (e.g.
accretion discs in active galactic nuclei) typically extend far beyond the
relativistic domain and are fairly diluted. However, self-gravity is still
essential for their structure and evolution, as well as for their radiation
emission and the impact on the environment around. For example, a nuclear star
cluster in a galactic centre may bear various imprints of mutual star--disc
interactions, which can be recognised in observational properties, such as the
relation between the central mass and stellar velocity dispersion.Comment: Accepted for publication in CQG; high-resolution figures will be
available from http://www.iop.org/EJ/journal/CQ
Demography, Diagnosis and Complications of Spinal Cord Injury Patients in a Rehabilitation Center of Bangladesh
Background: Spinal cord injury and its health related complications pose a major impact on the overall morbidity and mortality as well as cause economic constrains. It was aimed at looking into the demographic distribution, diagnosis, as well as complications in patients with spinal cord injury.
Methods: The study was conducted at Centre for the Rehabilitation of the Paralysed (CRP) between 2012 and 2013 from 201 respondents with the help of a structured preformed pretested questionnaire by face to face interview.
Results: Out of 201 respondents 176 (87.6%) were male and 25 (12.4%) were female; majority of the patients were in their 3rd decade which consisted 28.6%, followed by 27.4% in between 21-30 years and 26.8% in between 41-50. Most of the respondents of this study had traumatic paraplegia (56.5%) and Buttock was found to be the predominant site for developing site pressure sore as evident form 67.5%.
Conclusion: Productive males are more prone to spinal cord injury and the most common diagnosis is paraplegia with the most risky area is buttock for developing pressure sore. The findings may add in the way of developing awareness among stakeholders regarding demography, diagnosis and the pattern of the complications in a country like Bangladesh
Microsecond Isomer at the N=20 Island of Shape Inversion Observed at FRIB
Excited-state spectroscopy from the first Facility for Rare Isotope Beams
(FRIB) experiment is reported. A 24(2)-s isomer was observed with the FRIB
Decay Station initiator (FDSi) through a cascade of 224- and 401-keV
rays in coincidence with nuclei. This is the only known
microsecond isomer () in the
region. This nucleus is at the heart of the island of shape inversion
and is at the crossroads of spherical shell-model, deformed shell-model, and ab
initio theories. It can be represented as the coupling of a proton hole and
neutron particle to , .
This odd-odd coupling and isomer formation provides a sensitive measure of the
underlying shape degrees of freedom of , where the onset of
spherical-to-deformed shape inversion begins with a low-lying deformed
state at 885 keV and a low-lying shape-coexisting state at 1058 keV. We
suggest two possible explanations for the 625-keV isomer in Na: a
spherical shape isomer that decays by or a deformed spin isomer that
decays by . The present results and calculations are most consistent with
the latter, indicating that the low-lying states are dominated by deformation.Comment: 7 pages, 5 figures, accepted by Physical Review Letter
Design, Analysis and Testing of a Novel Mitral Valve for Transcatheter Implantation
Mitral regurgitation is a common mitral valve dysfunction which may lead to heart failure. Because of the rapid aging of the population, conventional surgical repair and replacement of the pathological valve are often unsuitable for about half of symptomatic patients, who are judged high-risk. Transcatheter valve implantation could represent an effective solution. However, currently available aortic valve devices are inapt for the mitral position. This paper presents the design, development and hydrodynamic assessment of a novel bi-leaflet mitral valve suitable for transcatheter implantation. The device consists of two leaflets and a sealing component made from bovine pericardium, supported by a self-expanding wireframe made from superelastic NiTi alloy. A parametric design procedure based on numerical simulations was implemented to identify design parameters providing acceptable stress levels and maximum coaptation area for the leaflets. The wireframe was designed to host the leaflets and was optimised numerically to minimise the stresses for crimping in an 8 mm sheath for percutaneous delivery. Prototypes were built and their hydrodynamic performances were tested on a cardiac pulse duplicator, in compliance with the ISO5840-3:2013 standard. The numerical results and hydrodynamic tests show the feasibility of the device to be adopted as a transcatheter valve implant for treating mitral regurgitation
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