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Anti-idiotype antibodies and phage displayed peptides as antigenic mimics of a Mycoplasma capricolum subsp. capripneumoniae epitopeBenguric, Dubravka Roka 30 March 2006 (has links)
Contagious caprine pleuropneumonia (CCPP) is a highly contagious disease that affects goats in Africa and Asia resulting in great economic losses. The aetiological agent is Mycoplasma capricolum subsp. capripneumoniae (Mccp). It belongs to a group of organisms that are all associated with economically important diseases of ruminants and all exhibit similar genetic and antigenic characteristics. The diagnosis of CCPP has often been considered difficult due to confusion with other mycoplasmas of ruminants and the limited specificity of most diagnostic assays. It is therefore important to improve diagnosis and thereby the control of CCPP. Two approaches, namely phage display and anti-idiotype antibodies can be used to identify antigenic mimics with the potential to be used in developing new vaccines, diagnostic methods or therapeutics. Both were used in an attempt to generate surrogate antigens for Mccp. A monoclonal antibody (Mab) or its F( ab ')2 fragments directed against Mccp membrane protein epitopes was injected into hens to induce the production of anti-idiotype antibodies. The antibodies produced were functionally able to mimic the epitope recognised by the Mab since they inhibited binding of the Mab to mycoplasmal lysate. Mice were also immunised with the Mab and or F(ab') 2 fragments of the antibody. The resulting antisera were tested in ELISA, but no significant response was detected. The selection of peptides from a random epitope library displayed on the surface of filamentous phages was used to characterise the epitope recognised by the Mab. Two different, but related peptides were identified that reacted with the antibody in enzyme-linked immunosorbent assays (ELISA). Binding to the Mab was further characterised by surface plasmon resonance. Sequence analysis revealed that the two peptides each had a cysteine residue in addition to the one fixed in amino acid position 2 as well as identical or similar amino acid residues in positions 5 (P), 8 (I/L) and 13 (L). One of the peptides had 74% similarity with an amino acid sequence of the PG 1 strain of Mycoplasma mycoides subsp. mycoides SC. The peptides as well as the anti-idiotype antibodies were not detectable using Mccp-specific goat antiserum suggesting that the serum did not contain paratopes that could accommodate the surrogate epitopes. In spite of this, the antiserum efficiently inhibited the binding of the Mab to immobilised mycoplasmal lysate in a standardised test for Mccp antibodies. This assay therefore appears to depend on a structural, rather than a functional blocking of the epitope which the Mab recognises. The findings in this study have elucidated some of the characteristics of the Mab and raised the possibility that the epitope recognised by the Mab is not immunodominant. Peptides identified by phage display and chicken/murine anti-idiotype antibodies, nevertheless, have the potential of being used as antigens in immunoassays aimed at CCPP diagnosis. In light of the results generated it would therefore be necessary to investigate other Mabs or polyclonal antiserum in order to yield antibodies or peptides of the desired specificity. / Dissertation (MSc (Microbiology))--University of Pretoria, 2007. / Microbiology and Plant Pathology / unrestricted
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Socio-ecological drivers of primate social network dynamics and implications for individual fitnessMurphy, Derek January 2015 (has links)
Social animals, such as primates, incur many fitness-related costs as a direct result of living in groups of conspecifics. However, group-living also comes with benefits. Sociality is thought to have evolved in response to the need for individuals to negotiate their social environment in order to maximise the benefits and minimise the costs associated with group-living. Recently, researchers interested in animal sociality have turned to a set of sophisticated statistical tools, collectively termed 'social network analysis' in order to better understand the structure of animal social systems and the role of individuals within their social groups. Using a social network analytic approach, I explore the relationship between the ecological and social environments, and the implications of an uncertain social landscape for individual fitness and fitness-relevant processes in two species of Old-World monkeys: chacma baboons (Papio hamadryas ursinus) and vervet monkeys (Chlorocebus aethiops pygerythrus). My results suggest that individuals respond to fluctuating local conditions in diverse ways depending on behavioural context and their current reproductive state, and that the social environment experienced by an individual, and their active pattern of social engagement has important implications for infant survival. Finally, I investigate how network structure influences two fitness-relevant processes of flow in a population of vervet monkeys: information transfer and disease transmission. I conclude that the complex social life of animal groups emerges from many individuals trying to achieve the same fitness goals. Successful individuals exploit the complexity in their social environment and respond adaptively to an uncertain and inconstant set of local conditions by actively adopting social strategies that serve to enhance their fitness.
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Antibiotic Resistance and Resistance Mechanisms in Bacteria Isolated from the Deep Terrestrial SubsurfaceUnknown Date (has links)
Various natural environments have been examined for the presence of antibiotic-resistant bacteria and/or novel resistance mechanisms, but little is known about resistance in the terrestrial deep subsurface. This study examined two deep environments that differ in their known period of isolation from surface environments and the bacteria therein. One hundred and fifty-four strains of bacteria were isolated from sediments located 170-259 m below land surface at the U.S. Department of Energy Savannah River Site (SRS) in South Carolina and Hanford Site (HS) in Washington. Analyses of 16S rRNA gene sequences showed that both sets of strains were phylogenetically diverse and could be assigned to several genera in 3-4 phyla. All of the strains were screened for resistance to 13 antibiotics by plating on selective media and 90% were resistant to at least one antibiotic. 86% of the SRS and 62% of the HS strains were resistant to more than one antibiotic. Resistance to naladixic acid, mupirocin, or ampicillin was noted most frequently. The results indicate that antibiotic resistance is common among subsurface bacteria. The somewhat higher frequencies of resistance and multiple resistance at the SRS may, in part, be due to recent surface influence, such as exposure to antibiotics used in agriculture. However, the HS strains have never been exposed to anthropogenic antibiotics but still had a reasonably high frequency of resistance. Given their long period of isolation from surface influences, it is possible that they possess some novel antibiotic resistance genes and/or resistance mechanisms. Seven of the strains from the HS that are resistant to tetracycline were examined for the presence of a novel antibiotic resistance gene. From these seven strains, a novel tetracycline resistance determinant was characterized. The predicted amino acid sequence shares only a 30% sequence similarity with TetA(Z), the most closely related previously described determinant. The new protein is a putative efflux pump with several characteristics in common with previously characterized efflux pumps including: a divergently transcribed TetR repressor, conserved GxxSDRxGRR motif, and transmembrane domains. The determinant has been assigned the name Tet 42. Functional genes from another subset of 11 HS strains that are resistant to ciprofloxacin were sequenced for resistance-conferring mutations. The most common mechanism of resistance to this antibiotic is based on mutations in the functional genes for DNA gyrase (gyrA, gyrB) and topoisomerase II (parC, parE). Sequences for the genes gyrA, gyrB, and parC in resistant strains were compared to the same sequences from ciprofloxacin-sensitive strains from the HS and Escherichia coli. The strains grouped into three genera: Arthrobacter, Sphingomonas, and Pseudomonas. All of the resistant strains possessed some mutations in their gyrase and/or topoisomerase genes that result in the substitution of amino acids not seen in the gene products of E. coli and the sensitive strains. These mutations, some of which have not been reported previously, can be considered putative resistance-conferring mutations. The resistant subsurface strains were also grown in the presence of an efflux pump inhibitor, and a majority of the cultures did not grow when the inhibitor was added. Lack of growth in the presence of the inhibitor may indicate that ciprofloxacin resistance is due entirely or in part to an efflux pump. The presence of an efflux pump might also explain why some of the strains with a higher minimum inhibitory concentration (MIC) have fewer mutations in their gyrase and/or topoisomerase genes than do strains with a lower MIC. It is possible that, along with novel mutations that may play a role in resistance, these strains also posses an uncharacterized efflux pump. A third approach used in this study to examine novel antibiotic resistance mechanisms was to look at differences in the entire proteome under normal and stressed conditions. The strain G887 is resistant to tetracycline and possesses the tetracycline resistance determinant Tet 42. Cultures of this strain were grown with tetracycline and without tetracycline. Protein extractions were performed from each culture and separated in the 1st dimension according to pI, on 4-7 Isoelectric Focusing Strips (IEF) strips and 6-11 IEF strips. After the 1st dimension separation, the proteins were separated by molecular weight on 12% acrylamide gels. The gels were stained with a fluorescent stain, imaged, and analyzed with spot analysis software. The gels run with the proteins from the tetracycline-treated culture indicated that several proteins visualized on both the 4-7 and 6-11 gels were upregulated in the presence of tetracycline. Some of these spots correspond to the molecular weight and pI for Tet A(42) or to those of several previously described general stress proteins. This work demonstrates that there is a high frequency of antibiotic resistance in the deep terrestrial subsurface and that bacteria in this environment possess uncharacterized antibiotic resistance genes and mutations that confer resistance. Given the constant emergence of antibiotic-resistant pathogenic strains in clinical settings and the problems this creates with respect to the treatment of bacterial diseases, it becomes increasingly important to characterize antibiotic resistance genes that may exist in the environment but have not yet been transferred to clinically important species. Our ability to alter existing antibiotics or develop new drugs to counter novel resistance mechanisms will be dependent on such characterizations. It might also be worthwhile to investigate subsurface bacteria for the ability to produce antibiotics themselves. There is a real potential for novel antibiotic discovery, given the length of time these bacteria have been isolated from antibiotic-producing bacteria in surface environments. / A Dissertation submitted to the Department of Biomedical Sciences in partial fulfillment of the requirements for the degree
of Doctor of Philosophy. / Fall Semester, 2008. / October 3, 2008. / Antibiotic Resistance, Bacteria, Subsurface / Includes bibliographical references. / David L. Balkwill, Professor Directing Dissertation; Hank W. Bass, Outside Committee Member; Graham A. Patrick, Committee Member; Branko Stefanovic, Committee Member.
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The relationship between food environment, obesity and NCD status among adults aged 30-70 years in Langa and Mount Frere, South Africa.Manuga, Tshilidzi January 2019 (has links)
Master of Public Health - MPH / Non-Communicable Diseases (NCDs) are some of the leading causes of death
worldwide. Obesity results from the interactions between biology, behaviour, and
environment. The current obesity epidemic is largely driven by environmental rather than
biological factors, through its influence on social norms regarding food choices and lifestyle
behaviours. The number of people dying from diabetes and hypertension keeps increasing
because of the current obesity trend.
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On the topic of Aerosol Generation and PropagationUnknown Date (has links)
In this research, three methods of aerosol generation, and their subsequent propagation, are investigated experimentally. These experiments provided insight into the potential risk aerosol can have pertaining to the spread of infectious disease such as COVID – 19. The first of which investigated an alternative generation route that may exist given the discovery of small numbers of viable viruses in urine and stool samples. Flushing biomatter can lead to the aerosolization of micro-organisms; thus, there is a likelihood that bioaerosols generated in public restrooms may pose a concern for the transmission of COVID-19, especially since these areas are relatively confined, experience heavy foot traffic, and may suffer from inadequate ventilation. The results indicate that the particular designs tested in the study generate a large number of droplets in the size range 0.3 𝜇𝑚 – 3 𝜇𝑚, which can reach heights of at least 1.52 m. This highlights the need for incorporating adequate ventilation in the design and operation of public spaces, which can help prevent aerosol accumulation in high occupancy areas and mitigate the risk of airborne disease transmission. Secondly, experiments were conducted to evaluate the effectiveness of facial coverings at various distances around a simulated cough. These concluded that due to the gaps along the seal of a face mask, aerosols can escape 360° around a coughing individual. In the final portion of the thesis study, an experimental method was developed and conducted to break up a droplet via mechanical excitation. The results of these experiments showed that when a droplet is placed on a vibrating string, the droplet can be broken into many secondary droplets which is analogous to one speaking or singing thus providing insight as to how vocal cords can generate respiratory aerosols. / Includes bibliography. / Thesis (MS)--Florida Atlantic University, 2021. / FAU Electronic Theses and Dissertations Collection
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Cytokine-Associated Neutrophil Extracellular Traps and Antinuclear Antibodies in Plasmodium Falciparum Infected Children under the Age of Six.Unknown Date (has links)
In Plasmodium falciparum-infected children, the relationships between blood cell histopathology, blood plasma components, development of immunocompetence, and disease severity remain poorly understood. This investigation relates levels of the pro-inflammatory cytokines IFN-g, IL-2, TNF-a, CRP, and IL-6, and select anti-inflammatory cytokines TGF-b and IL-10 to the formation of neutrophil extracellular nets (NETs), IgG antinuclear antibodies (ANA), and IgG antineutrophil cytoplasmic antibodies (ANCA) in blood collected before and seven days after initiation of Sulfadoxine-Pyrimethamine treatment from 21 Nigerian children under six years old presenting with uncomplicated malaria. The children exhibited a Th2 dominated cytokine profile and left-shifted leukocyte differential. Elevated TNF-a levels correlated with significant NET formation evident in the peripheral blood smears. ANA levels (inclusive of all subsets of ANA) were significant in 86% of the children pretreatment and in 100% of the children seven days after SP treatment but in only 33% of age-matched control samples collected during the season of low parasite transmission. IgG ANA subset levels to dsDNA were significant in 81% of both the pre- and post treatment samples, whereas ANCA levels were positive in only 14% of both the pre-and post-treatment samples. Our results suggest that an inverse relationship between TGF-b and CRP levels may contribute to homeostasis and that TNF-a-associated NET formation and ANA may induce pathology in falciparum-infected children or activate a protective mechanism against falciparum malaria in adults. The significance of in vivo circulating chromatin in NETs and ANA to dsDNA as a causative factor in the hyporesponsiveness of CpG olignucleotide-based malaria vaccines is discussed. / A Dissertation submitted to the Department of Biological Science in partial
fulfillment of the requirements for the degree of Doctor of Philosophy. / Degree Awarded: Spring Semester, 2007. / Date of Defense: April 5, 2007. / Anti-Neutrophil Cytoplasmic Antibodies, Innate Immune Protection, ANA, ANCA, Neutrophil Extracellular Traps, Falciparum Malaria, Vaccine Hyporesponsiveness, Nets, Anti-Nuclear Antibodies, Autoimmunity, Cytokines / Includes bibliographical references. / Thomas Keller, III, Professor Directing Dissertation; Qing-Xiang Sang, Outside Committee Member; Robert H. Reeves, Committee Member; Kenneth H. Roux, Committee Member; Wu-Min Deng, Committee Member.
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Investigation of Reasons Children are UnvaccinatedClawson, Tracy L. 01 January 2015 (has links)
Many communicable diseases can be prevented with the use of immunizations. The issue this study addressed was the use of vaccinations and the rise of continued preventable communicable disease. Researchers have recommended that children be vaccinated, a recommendation that is bolstered by the readily available supply of vaccinations worldwide. However, even with vaccine promotions, availability, and education, children continue to be unvaccinated and outbreaks have continued to occur. For this study, data will be collected from the Iowa Registry of Immunization Records and a local community health center pediatric clinic. Examples of data that will be collected are vaccine records, race, and language spoken. Also, data from questionnaires given to parents, caregivers, and medical staff will be obtained to discover their beliefs, misconceptions, and thoughts on vaccines. The sample size will be 35, with recruitment occurring when the parent brings a child into the clinic for a well child or sick visit. The questionnaires will be collected and analyzed by totaling the responses from a pre-existing Likert scale questionnaire.The purposes of the project are to (a) discuss with health care providers a project, that consists of reasons children are not vaccinated; (b) develop a plan to determine those reasons and how to educate parents, the community being served by this health care facility and health care staff on the importance of immunizations; (c) and promote vaccinations for the this community.
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An Exploration of Hepatitis Polices and Prevalence in Prison: An Ecological ApproachStives, Kristen Lynn 09 May 2015 (has links)
Hepatitis is an infectious disease that affects millions of people worldwide. The current project seeks to achieve two objectives: 1) To understand how hepatitis policies affect hepatitis prevalence in prison, and 2) To understand how hepatitis prevalence in prison affects the general population. Using a content analysis of correctional policies available through each state Department of Corrections (DOC) and secondary data from the 2010 Census, Centers for Disease Control and Prevention, and Corrections Compendium; hepatitis prevalence and policies are analyzed. The content analysis employed for this study revealed that some states have more comprehensive policies than others. However, all states may benefit from modifying their policies to meet recommendations constructed by the Federal Bureau of Prisons. Findings from descriptive statistics also suggest changes in HIV prevalence and policies positively affect hepatitis C prevalence. Future research should be dedicated to examining how personal interactions in prison also affect prevalence rates.
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A Survey of Control Measures Employed for Specific Communicable Diseases in Defiance County Public SchoolsGecowets, Max E. January 1949 (has links)
No description available.
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A Survey of Sterilization/Disinfection Techniques Used By Orthodontists in the U.S.Burns, Richard H. January 1986 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Questionnaires were sent to 500 orthodontists in all states of the U.S., inquiring about the methods of sterilization used for hand instruments (mirrors, explorers, band pushers, etc.) and hinged instruments (pliers). The practitioners were asked if their sterilization/disinfection methods had been changed recently, and if any changes in methods were due to the risk of disease transmission. Opinions were also solicited regarding the importance of complete sterilization (i.e., destruction of all organisms). An opportunity was provided to rate the effectiveness of the sterilization method in use. Finally, information was requested on any barrier methods used routinely.
The most commonly used method for hand and hinged instruments was cold sterilization with a 2% glutaraldehyde solution. This solution was used by 46.5% of the office for hand instruments, and by 33.5% of the offices for hinged instruments. Quaternary ammonium compounds were used by 26.5% of the offices for hand instruments, and by 19.2% for hinged instruments. Wiping with alcohol was used by 30.4% of the offices for hinged instruments. The most common heat sterilization method used was the chemiclave system (11.5% for hand instruments and 9.1% for hinged).
Of the offices surveyed, 45.5% had changed their methods within the past two years. Of that group, 66.9% had changed as a result of the increased problem with transmissible diseases. Of the offices that had not changed recently, 64.1% were considering doing so as a result of the disease transmission concern. Complete sterilization was considered very important by 47.5% of respondents, while 41.6% ranked it somewhat important. Of the orthodontists surveyed, 16.1% felt that they achieved an excellent level of asepsis in their offices, followed by 58.7% who rated it good, 23.4% average, and 1.4% poor. Protective eyewear was worn by 52.4 % of those surveyed, while gloves and masks were worn routinely by 21.3% and 21.6% of the practitioners, respectively.
On the basis of the literature review, the most effective cold sterilization method (other than ethylene oxide) for the orthodontic office appears to be a 2% glutaraldehyde solution. This technique will not corrode plier joints or the stainless steel surfaces. The best heat sterilization method for the orthodontic office is the chemiclave system, due to its lack of corrosion problems, as well as its relatively rapid cycle time. Ultrasonic cleaning of all instruments prior to sterilization is highly recommended.
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