554 research outputs found
Protective efficacy of a recombinant plague vaccine when co-administered with another sub-unit or live attenuated vaccine.
Vaccines against bioterrorism agents offer the prospect of providing high levels of protection against airborne pathogens. However, the diversity of the bioterrorism threat means that it may be necessary to use several vaccines simultaneously. In this study we have investigated whether there are changes to the protective immune response to a recombinant sub-unit plague vaccine when it is co-administered with other sub-unit or live attenuated vaccines. Our results indicate that the co-administration of these vaccines did not influence the protection afforded by the plague vaccine. However, the co-administration of the plague sub-unit vaccine with a live vaccine resulted in markedly increased levels of IgG2a subclass antibodies, and markedly reduced levels of IgG1 subclass antibodies, to the plague sub-unit vaccine. This finding might have implications when considering the co-administration of other vaccine combinations
After the introduction of EUS-guided drainage, is there still a role for endoscopic transpapillary gallbladder stent placement for patients who are not fit for cholecystectomy?
The oxalate complexes of thorium
(1) The ammonium, potassium and sodium salts of three complex thorium oxalates were prepared and studied. (2) Their solubilities and conditions of stability were studied. (3) The reaction between thorium and excess oxalate, and vice versa, was studied by means of conductivity and high frequency conductivity measurements. (4) The formation constant of Th(C₂O₄)₄⁴⁻ and Th(C₂O₄)₃²⁻, and the solubility product of (NH₄)₂Th₂(C₂O₄)₅, were determined by a solubility method
Nonlinear fault detection and diagnosis using Kernel based techniques applied to a pilot distillation colomn
Fault detection and diagnosis is an important problem in process engineering. In this dissertation, use of multivariate techniques for fault detection and diagnosis is explored in the context of statistical process control. Principal component analysis and its extension, kernel principal component analysis, are proposed to extract features from process data. Kernel based methods have the ability to model nonlinear processes by forming higher dimensional representations of the data. Discriminant methods can be used to extend on feature extraction methods by increasing the isolation between different faults. This is shown to aid fault diagnosis. Linear and kernel discriminant analysis are proposed as fault diagnosis methods. Data from a pilot scale distillation column were used to explore the performance of the techniques. The models were trained with normal and faulty operating data. The models were tested with unseen and/or novel fault data. All the techniques demonstrated at least some fault detection and diagnosis ability. Linear PCA was particularly successful. This was mainly due to the ease of the training and the ability to relate the scores back to the input data. The attributes of these multivariate statistical techniques were compared to the goals of statistical process control and the desirable attributes of fault detection and diagnosis systems.Dissertation (MEng (Control Engineering))--University of Pretoria, 2008.Chemical EngineeringMEngUnrestricte
Improved Efficacy of a Gene Optimised Adenovirus-based Vaccine for Venezuelan Equine Encephalitis Virus
<p>Abstract</p> <p>Background</p> <p>Optimisation of genes has been shown to be beneficial for expression of proteins in a range of applications. Optimisation has increased protein expression levels through improved codon usage of the genes and an increase in levels of messenger RNA. We have applied this to an adenovirus (ad)-based vaccine encoding structural proteins (E3-E2-6K) of Venezuelan equine encephalitis virus (VEEV).</p> <p>Results</p> <p>Following administration of this vaccine to Balb/c mice, an approximately ten-fold increase in antibody response was elicited and increased protective efficacy compared to an ad-based vaccine containing non-optimised genes was observed after challenge.</p> <p>Conclusion</p> <p>This study, in which the utility of optimising genes encoding the structural proteins of VEEV is demonstrated for the first time, informs us that including optimised genes in gene-based vaccines for VEEV is essential to obtain maximum immunogenicity and protective efficacy.</p
Development of a novel monoclonal antibody with reactivity to a wide range of Venezuelan equine encephalitis virus strains
<p>Abstract</p> <p>Background</p> <p>There is currently a requirement for antiviral therapies capable of protecting against infection with Venezuelan equine encephalitis virus (VEEV), as a licensed vaccine is not available for general human use. Monoclonal antibodies are increasingly being developed as therapeutics and are potential treatments for VEEV as they have been shown to be protective in the mouse model of disease. However, to be truly effective, the antibody should recognise multiple strains of VEEV and broadly reactive monoclonal antibodies are rarely and only coincidentally isolated using classical hybridoma technology.</p> <p>Results</p> <p>In this work, methods were developed to reliably derive broadly reactive murine antibodies. A phage library was created that expressed single chain variable fragments (scFv) isolated from mice immunised with multiple strains of VEEV. A broadly reactive scFv was identified and incorporated into a murine IgG2a framework. This novel antibody retained the broad reactivity exhibited by the scFv but did not possess virus neutralising activity. However, the antibody was still able to protect mice against VEEV disease induced by strain TrD when administered 24 h prior to challenge.</p> <p>Conclusion</p> <p>A monoclonal antibody possessing reactivity to a wide range of VEEV strains may be of benefit as a generic antiviral therapy. However, humanisation of the murine antibody will be required before it can be tested in humans.</p> <p>Crown Copyright © 2009</p
Shifting hegemony in ‘a man’s world’: incremental change for female golf professional employment
There is much evidence to suggest that the golf environment is unequal in terms of gender. This study puts this to the test by focusing on female golf professionals’ understanding of the barriers and opportunities to employment in the golf industry. Data were collected through a series of focus groups, interviews (n = 17) and a survey (n = 95) with female PGA professionals and trainee PGA professionals in Great Britain and Ireland, over half of whom indicated coaching as their primary employment role. At the time of data collection female PGA golf professionals made up less than 3% of all PGA professionals in Britain and Ireland. The data revealed some clear differences between older and younger respondents on barriers to, and opportunities for, employment in the golf industry. On the whole, younger professionals appeared more willing to challenge, discuss and confront the underlying discrimination. The results suggest that golf is undergoing an incremental change away from male hegemony
Increased immune response elicited by DNA vaccination with a synthetic gp120 sequence with optimized codon usage
DNA vaccination elicits humoral and cellular immune responses and has been shown to confer protection against several viral, bacterial, and parasitic pathogens. Here we report that optimized codon usage of an injected DNA sequence considerably increases both humoral and cellular immune responses. We recently generated a synthetic human immunodeficiency virus type 1 gp120 sequence in which most wild-type codons were replaced with codons from highly expressed human genes (syngp120). In vitro expression of syngp120 is considerably increased in comparison to that of the respective wild-type sequence. In BALB/c mice, DNA immunization with syngp120 resulted in significantly increased antibody titers and cytotoxic T-lymphocyte reactivity, suggesting a direct correlation between expression levels and the immune response. Moreover, syngp120 is characterized by rev-independent expression and a low risk of recombination with viral sequences. Thus, synthetic genes with optimized codon usage represent a novel strategy to increase the efficacy and safety of DNA vaccination
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