Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-07-10T13:03:11Z No. of bitstreams: 1 2010 - Daniel da Silva Guedes Junior .pdf: 3397672 bytes, checksum: fea6a394bbb430b666ddc9c054a24c27 (MD5) / Made available in DSpace on 2017-07-10T13:03:11Z (GMT). No. of bitstreams: 1 2010 - Daniel da Silva Guedes Junior .pdf: 3397672 bytes, checksum: fea6a394bbb430b666ddc9c054a24c27 (MD5) Previous issue date: 2010-02-10 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq, Brasil. / The geographic distribution of bovine borreliosis is determined by the dispersion of its vector. Borrelia theileri is the predominant species in cattle, and B. coriaceae and B. burgdorferi also been reported causing clinical disease. B. theileri cause mild disease in cattle, and still is important for its potential to be confused with the spirochete of Lyme disease, B. burgdorferi, and agents of epizootic bovine abortion, B. coriaceae. In Brazil, as well as in other South American countries, the agent of this disease has not been isolated further confusing the diagnosis. The objective of this study was to identify genotypically Borrelia sp that affects cattle in Brazil. DNA extraction, was performed from blood and ticks of cattle with positive serology by indirect ELISA with crude antigen of Borrelia burgdorferi. Primers were designed for genes of Borrelia burgdorferi and B. theileri groups: 16S, flaA, flaB, GroEL, hbb, recA, 5s-23s, p66, rrs, rpoB and glpq. After the PCR reaction, only the primers amplified rrs and rpoB sequences. The predictive amino acid sequence of RRS3 revealed 99% homology with B. hermsii and B. duttonii and predictive amino acid sequence of RPOB showed 67% homology with B. duttonii and B. recurrentis. This suggests that the species of Borrelia sp present in Brazil is not owned by group B. burgdorferi. Little is known regarding the genetic variability of genes that encode membrane proteins of Brazilian isolates of A. marginale. The products of these genes constitute an important tool, as there may be significant antigen polymorphism, which may damage cross-protection between isolates and the chances of identifying candidate immunogens. The aim of the present study was to determine the degree of conservation of sequences of these genes in a Brazilian isolate of A. marginale comparing with Saint Maries and Florida isolates. For this, primers were designed to amplify the genes omp1, omp4, omp5, omp7, omp8, omp10, omp14, omp15, sodb, opag1, opag3, virb3, am097 (VirB9-1), am956 (PepA), am254 (ef-tu), am854 by PCR. The genes were then sequenced by Sanger method and the predicted amino acid sequences aligned and homology analyzed by the program CLUSTAL W. With the exception of OMP 7 all proteins (OMP1, OMP4, OMP5, OMP8, OMP10, OMP14, OMP15, SODB, OPAG1, OPAG3, VIRB3, VIRB9-1, PepA, EF-Tu, AM854) exhibited homology greater than 92% with other A. marginale isolates. However, only OMP1, OMP5, EF-Tu, VirB3, SODB, VIRB9-1 e AM854 showed homology greater than 72% regarding to A. marginale centrale which confers cross-protection against A. marginale. / A distribui??o geogr?fica da borreliose bovina ? determinada pela dispers?o do seu vetor. Borrelia theileri ? a esp?cie predominante em bovinos, sendo que B. burgdorferi e B. coriaceae tamb?m foram relatadas causando doen?a cl?nica. Portanto, B. theileri causa doen?a leve em bovinos, e ainda ? importante pelo seu potencial em ser confundido com a espiroqueta da Doen?a de Lyme, B. burgdorferi, e com agentes do Aborto Epizo?tico bovino, B. coriaceae. No Brasil, assim como em outros pa?ses Sul americanos, o agente desta enfermidade ainda n?o foi isolado prejudicando ainda mais o diagn?stico. O objetivo deste trabalho foi ? identifica??o genot?pica da esp?cie de Borrelia sp que acomete bovinos no Brasil. Foram utilizados para extra??o de DNA, o sangue e carrapatos de bovinos com sorologia positiva ao ELISA indireto com ant?geno bruto para Borrelia burgdorferi. Foram desenhados oligonucleot?deos iniciadores para genes dos grupos Borrelia burgdorferi e B. theileri: 16S, flaA, flaB, groel, hbb, recA, 5s-23s, p66, rrs, rpob e glpq. Ap?s a rea??o de PCR, somente os oligonucleot?deos iniciadores rrs e rpob amplificaram seq??ncias. A seq??ncia preditiva de amino?cidos de RRS3 revelou homologia de 99% com B. hermsii e B. duttonii e a seq??ncia preditiva de amino?cidos de RPOB demonstrou 67% de homologia com B. duttonii e B. recurrentis. Isto sugere que a esp?cie de Borrelia presente no Brasil n?o seja pertencente ao grupo de B. burgdorferi. Pouco se sabe sobre a variabilidade gen?tica dos genes que codificam prote?nas de membrana de isolados brasileiros de A. marginale. O produto destes genes constitui uma ferramenta importante, pois pode haver polimorfismo antig?nico, que pode prejudicar a prote??o cruzada entre os isolados e as chances de identifica??o de candidatos a imun?genos. O objetivo do presente estudo foi determinar o grau de conserva??o das seq??ncias destes genes em um isolado brasileiro de A. marginale frente aos isolados Saint Maries, Florida e A. marginale centrale. Para tanto, oligonucleot?deos foram desenhados para amplificar os genes omp1, omp4, omp5, omp7, omp8, omp10, omp14, omp15, sodb, opag1, opag3, virb3, am097 (VirB9- 1), am956 (PepA), am254 (ef-tu), am854 por PCR. Os genes foram ent?o seq?enciados pelo m?todo de Sanger e as seq??ncias preditas de amino?cidos alinhadas e a homologia analisada atrav?s do programa CLUSTAL W. Com exce??o de OMP 7 todas as demais (OMP1, OMP4, OMP5, OMP8, OMP10, OMP14, OMP15, SODB, OPAG1, OPAG3, VIRB3, VIRB9-1, PepA, EF-Tu, AM854) apresentaram n?veis de homologia de 92 a 100% entre os isolados de A. marginale. Destas, apenas OMP1, OMP5, EF-Tu, VirB3, SODB, VIRB9-1 e AM854 apresentaram homologia superior a 72% em rela??o a A. marginale centrale, o qual confere prote??o cruzada contra A. marginale.

Background: Every year approximately 5 000-10 000 persons in Sweden are diagnosed for Lyme disease. In Europe the incidence is about 65 000 persons per year. Lyme disease is a tick-borne zoonosis, the causative agents – Borrelia burgdorferi-genospecies - are transmitted by Ixodes-ticks (in Sweden primary I.ricinus). Lyme disease is treated with antibiotic-therapy. Though, in 5-15 percent of the cases, post-treatment symptoms can appear and persist for six months, or longer. Today we don´t know the origin of the phenomena. Some patients seek help outside the Swedish borders, and turn to so called Lyme disease-clinics – which, in some cases, institutes long-term antibiotic-treatment. The pharmacist may encounter this particular matter, while carrying out EES-antibiotic-prescriptions, prescribed non-analogous to Swedish guidelines.  Objective: The aim of this study was to investigate the efficacy of doxycycline, with respect to short-, middle-, and long-term Lyme disease-treatment. The intention was also to investigate the pharmacist role in executing EES-antibiotic-prescriptions.  Methods: The study was divided into two parts. The first part was investigating doxycycline, and was based on five scientific articles collected from PubMed. The second part was a review of the pharmacist role in processing EES-antibiotic-prescriptions; information was collected by email correspondence with pharmacy chain stores, authorities and federation of labor unions.  Results: Awareness and protective measures regarding ticks and Lyme disease seems dire. Improved diagnostic methods, uniform interpretation of outcome, standardized laboratory-analysis is of paramount importance. The pharmacist concerns with EES-antibiotic-prescriptions is carrying out the medical prescription and giving medical advice. Doxycycline in 10-14 days Lyme disease-treatment was seen as an alternative, supported by Swedish guidelines. The post-exposure prophylaxis was not a recommended alternative. Regarding doxycycline and long-term Lyme-disease-treatment, it was postulated that additional scientific studies was needed. Conclusions: The tick, vector of Borrelia burgdorferi, will be favoured of recent and upcoming climate changes. In the future to come, we can expect an expansion of the tick-habitats and with it follows the probability of more frequent encounters with the human race. This will most likely contribute to a higher incidence of Lyme disease. Prevention and subject-enlightenment is of need. The pharmacist will in the professional role be exposed to daily moral dilemmas; one of these dilemmas can be the execution of EES-antibiotic-prescriptions, not prescribed accordingly to Swedish guidelines, with respect to Lyme disease. As things stand today, the primary commitment will be medical advice and carrying out the prescription. The post-exposure prophylaxis regarding doxycycline and Lyme disease is not recommended. The 10-14 days doxycycline-cure, regarding some Lyme disease-manifestations, is mostly a preferable alternative today. Prolonged antibiotic-treatment with doxycycline, in respect to post-treatment symptoms, needs to be further evaluated with better diagnostic methods, scientific studies, standardized analysis and more uniform interpretation of results.

abstract: Borrelia burgdorferi (Bb), the causative agent of Lyme disease, is a unique pathogen, with a complex genome and unique immune evasion tactics. It lacks genes encoding proteins involved in nutrient synthesis and typical metabolic pathways, and therefore relies on the host for nutrients. The Bb genome encodes both an unusually high number of predicted outer surface lipoproteins of unknown function but with multiple complex roles in pathogenesis, and an unusually low number of predicted outer membrane proteins, given the necessity of bringing in the required nutrients for pathogen survival. Cellular processing of bacterial membrane proteins is complex, and structures of proteins from Bb have all been solved without the N-terminal signal sequence that directs the protein to proper folding and placement in the membrane. This dissertation presents the first membrane-directed expression in E. coli of several Bb proteins involved in the pathogenesis of Lyme disease. For the first time, I present evidence that the predicted lipoprotein, BBA57, forms a large alpha-helical homo-multimeric complex in the OM, is soluble in several detergents, and purifiable. The purified BBA57 complex forms homogeneous, 10 nm-diameter particles, visible by negative stain electron microscopy. Two-dimensional class averages from negative stain images reveal the first low-resolution particle views, comprised of a ring of subunits with a plug on top, possibly forming a porin or channel. These results provide the first evidence to support our theories that some of the predicted lipoproteins in Bb form integral-complexes in the outer membrane, and require proper membrane integration to form functional proteins. / Dissertation/Thesis / Doctoral Dissertation Chemistry 2020

Relapsing fever Borrelia are transmitted through saliva of argasid ticks. Given the 10 to 60 minute long bloodmeal, we characterized the rapidity of Borrelia turicatae transmission from their vector Ornithodoros turicata. Infection rates were compared in mice when cohorts of ticks fed to repletion on animals in which groups of O. turicata were removed 15 seconds after attachment. Infection was evaluated by examining the blood by dark field microscopy, quantitative PCR, and serological responses generated against B. turicatae. Scanning electron microscopy was also performed on cryofractured tick salivary glands to determine spirochete localization. Dissemination of B. turicatae into murine blood was evaluated by removing the bite site after ticks engorged. Our findings indicate that B. turicatae is localized in the lumen of salivary gland acini of O. turicata and transmission to and dissemination in the mammal occur shortly after tick attachment and do not require a complete bloodmeal.

Borrelia burgdorferi is the etiological agent of Lyme disease. Not much is known about the susceptibility of this organism to chemical disinfection. Current antimicrobial susceptibility test methods, such as those published by the American Society for Testing and Materials (ASTM), usually require assessment of the number of colony forming units (cfu) of growing organisms on plates following exposure to an agent. For fast-growing organisms, plates are ready for counting 1-2 days post plating, while several weeks may be needed for slower growing organisms. Spirochetes, like B. burgdorferi are difficult to grow on solid media and typically require long incubation periods, sometimes up to several weeks, to generate visible colonies. These issues make B. burgdorferi cfu assessment by plate counting difficult and unreliable. Furthermore, Borrelia have a demonstrated capacity for pleomorphic forms, and can exist in spirochete, round body, or biofilm forms, depending on culture conditions. Plate counts, by nature, do not allow for assessment of morphological form changes. Additionally, the susceptibility of B. burgdorferi pleomorphic forms to chemical disinfectants has not been tested. In this study, we used the SYBR GREEN I/Propidium Iodide (SG I/PI) viability assay to rapidly estimate the percent kill of B. burgdorferi pleomorphic forms to chemical disinfection. Planktonic spirochete populations in 30-second treated samples showed viability percent values of: >95% for Hanks balanced salt solution (HBSS), ~60% for distilled deionized H2O (dd H2O), <5% for ACS 200, and 1% for 1% glutaraldehyde (GTA). Solutions containing 70% ethanol (ETH) and 1% hypochlorite (HC) showed no viable spirochetes following treatment. The percent of live round body cells following different treatments were: >99% for HBSS and <25% for dd H2O. ACS 200, 1% GTA, and 70% ETH treatments resulted in <1% live round body forms, whereas HC showed no live round cell forms. The susceptibility of B. burgdorferi biofilms to various treatments was also assayed using a SG I/PI viability stain after 30-minute contact times. The percent of viable organisms (green) in the treated biofilms was estimated by microscopic observations. HBSS controls showed >98% of bacteria in the biofilm were alive, while treated biofilms showed the following percent viabilities: ACS 200 - ~2%, 1% HC - <1%, 5% HC - <1%, 1% GTA - ~10%, 70% ETH - ~ 2%, and dd H2O ~40%. These techniques merged standardized assessment of antimicrobial activity in liquid culture using an ASTM-type kill-time procedure with viability techniques used in antibiotic susceptibility testing to rapidly evaluate the percent kill of B. burgdorferi pleomorphic forms in vitro following disinfectant exposure. These results showed that B. burgdorferi biofilm forms are orders of magnitude more resistant to chemical disinfection than other morphological forms of this organism.

The Western Fence Lizard (Sceloporus occidentalis) is a major host of juvenile stages of the Western Black-legged Tick (Ixodes pacificus), which is the vector for the Lyme disease causative spirochete bacterium Borrelia burgdorferi in the western United States. Because S. occidentalis is reservoir incompetent and capable of eliminating spirochetes from infected ticks, it has been implicated as a major factor in the ecology of Lyme disease in the West. Although complement proteins in lizard blood have been established as the borreliacidal factor, no studies have examined intraspecific variability in host lizard borreliacidal capacity. In Chapter 1 of this thesis, we introduce the complexity of the Borrelia burgdorferi transmission cycle and it’s implications for transmission risk. In Chapter 2 we tested the hypothesis that host lizard physiological condition impacts their borreliacidal capacity. Blood plasma of lizards in varying physiological conditions was challenged against cultured B. burgdorferi, and the complement-mediated inactivation of spirochetes was quantified. Adult lizards had higher bactericidal activity than first-year juveniles, suggesting that complement-mediated inactivation develops with maturity and/or exposure to spirochete antigens. Also, bactericidal activity was positively associated with lizard tick load and body condition. Adult lizard sex did not significantly affect spirochete mortality. Lizards from an inland site with little exposure to ticks had higher bactericidal activity than lizards from a coastal population that is heavily parasitized by ticks.

The macrophage receptors that mediate phagocytosis of Borrelia burgdorferi, the Lyme disease spirochete, are unknown despite this cell type's importance in promoting pathogen clearance and inflammation-mediated tissue damage. We now demonstrate that the β2 integrin, Complement Receptor 3 (CR3), mediates the phagocytosis of opsonized and non-opsonized spirochetes by murine macrophages and human monocytes. Although, expression of the surface proteins, CspA and OspE, protects B. burgdorferi from complement-mediated phagocytosis, the versatility of CR3 counteracts the ability of B. burgdorferi to interfere with complement activation and complement-derived opsonins, thus minimizing the bacteria's anti-complement strategy. Interaction of the spirochete with the integrin is not sufficient to internalize B. burgdorferi; however, phagocytosis occurs when the GPI-anchored protein, CD14, is coexpressed in CHO-CR3 cells. CR3-mediated phagocytosis occurs independently of MyD88-induced or inside-out signals but requires the translocation of the integrin to cholesterol rich membrane microdomains. Interestingly, the absence of CR3 leads to marked increases in production of TNF in vitro and in vivo, in spite of reduced spirochetal uptake. Overall, our data establish CR3 as a MyD88-independent phagocytic receptor for B. burgdorferi that also participates in the modulation of the proinflammatory output of macrophages. Macrophages are critical cellular components of the immune response to infectious agents. During infection with B. burgdorferi, macrophages infiltrate the cardiac tissue and induce the activation of invariant NKT cells, leading to the production of the protective cytokine IFNγ. The interaction of macrophages with infectious agents leads to the activation of several signaling cascades, including mitogen activated protein kinases, such as p38 MAP kinase. We now demonstrate that p38 MAP kinase-mediated responses are critical components to the immune response during infection with B. burgdorferi. The inhibition of p38 MAP kinase does not alter the ability of macrophages to phagocytose B. burgdorferi; however, inhibition of p38 during infection with B. burgdorferi results in increased carditis. Through the generation of transgenic mice that express a dominant negative form of p38 MAP kinase specifically in macrophages, we demonstrate that this kinase regulates the production of the iNKT attracting chemokine, MCP-1 and the infiltration of these cells to the cardiac tissue during infection. Overall, the inhibition of p38 MAP kinase during infection with B. burgdorferi specifically in macrophages results in the deficient infiltration of iNKT cells and their diminished production of IFNγ, leading to increased bacterial burdens and inflammation. These results show that p38 MAP kinase provides critical checkpoints for the protective immune response to the spirochete during infection of the heart.

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