Dissertations / Theses on the topic 'Streptoccus equi'
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Steward, Karen Frances. "Comparative genomics of Streptococcus equi and Streptococcus zooepidemicus." Thesis, University of Cambridge, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708551.
Full textMaciel, Liana Flores. "Desenvolvimento de vacina recombinante de proteína M de Streptococcus equi subsp. equi." Universidade Federal de Pelotas, 2012. http://repositorio.ufpel.edu.br/handle/ri/1199.
Full textThe business related to equines in Brazil has an important participation in activities as leisure, culture and tourism, being responsible for millions of jobs. The equine distemper caused by Streptococcus equi subsp. equi is a disease of the respiratory tract with economical impact, generating losses with treatment and reduction in the animal performance. To solve this problem, prophylactic measures, such as the vaccination, are important. However, available commercial vaccines do not offer protection to more than 50% of the vaccinated animals. Several studies are being performed aiming the achievement of an efficient vaccine against the Adenitis, where several virulence factors are being evaluated as possible vaccine antigens, specially the M protein (SeM). Thus, the present work aimed the development and evaluation of a recombinant vaccine to the control of the equine distemper composed of the SeM antigen co-administrated with the recombinant Heat-labile enterotoxin B subunit of Escherichia coli (rLTB) and/or aluminium hydroxide (Al(OH)3). A total of 72 female BALB/c mice, divided into eight groups and 18 horses, divided into six groups, were inoculated by intramuscular or intranasal routes. The results obtained in the experiments showed that the rSeM was innocuous and immunogenic in both evaluated species, stimulating the production of specific immunoglobulin anti-rSeM without the addition of immunological adjuvant. Both adjuvant rLTB and Al(OH)3 were not capable to increase the titer of immunoglobulin anti-rSeM in mice, while in horses, the treatment rSeM + rLTB (IM) showed a significant increase in the level of seric immunoglobulin IgG anti-rSeM. Interestingly, the production of anti-rSeM secretory IgA in the upper respiratory tract has a significant increase in horses treated with rSeM + Al(OH)3 (IM). This result is promising to further studies with rSeM as an antigen for vaccines, as well as is the administration of rLTB as an immunological adjuvant.
A equinocultura no Brasil ganha espaço em setores ligados ao lazer, cultura e turismo, sendo responsável por milhões de empregos. A Adenite Equina causada pelo Streptococcus equi subsp. equi é uma doença do aparelho respiratório de elevado impacto econômico, gerando gastos com mão-de-obra e perda de desempenho dos animais. Para amenizar este problema, medidas profiláticas são importantes, como por exemplo, a vacinação. Porém, as vacinas disponíveis no mercado protegem apenas 50% dos animais. Vários estudos vêm sendo realizados para obtenção de uma vacina mais eficiente contra a Adenite, onde vários fatores de virulência do patógeno estão sendo avaliados como possíveis antígenos vacinais, com destaque para a proteína M de S. equi (SeM). Com base nisso este trabalho objetivou o desenvolvimento e avaliação de uma vacina recombinante para controle da Adenite Equina, utilizando como antígeno a rSeM e como adjuvantes a subunidade B da enterotoxina termolábil de Escherichia coli (rLTB) e ou hidróxido de alumínio (Al(OH)3). Para este estudo foram utilizados 72 camundongos Balb/c fêmeas divididos em 8 grupos e 18 cavalos divididos em 6 grupos, inoculados por via IM ou IN. Os resultados mostraram que a rSeM foi inócua e imunogênica para ambas as espécies avaliadas, estimulando níveis significativos de imunoglobulinas (lgs) anti-rSeM sem a necessidade de uso de qualquer adjuvante imunológico. Os adjuvantes rLTB e Al(OH)3 não foram capazes de incrementar significativamente os títulos de lgs antirSeM em camundongos, enquanto que em cavalos o tratamento rSeM + rLTB (IM) promoveu um aumento significativo no título sérico de IgG anti-rSeM. Interessantemente, a produção de IgA secretória anti-rSeM no trato respiratório superior de cavalos teve aumento significativo no tratamento com rSeM + Al(OH)3 (IM). Estes resultados são promissores para a continuidade de estudos visando a utilização da rSeM como antígeno vacinal. Da mesma forma, o uso da rLTB como adjuvante em vacinas para cavalos parece ser promissor.
De, Negri Rafaela. "EQUINE SERUM ANTIBODY RESPONSES TO STREPTOCOCCUS EQUI AND STREPTOCOCCUS ZOOEPIDEMICUS." UKnowledge, 2013. http://uknowledge.uky.edu/gluck_etds/13.
Full textLannergård, Jonas. "Potentially virulence-related extracellular proteins of Streptococcus equi /." Uppsala : Dept. of Microbiology, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200680.pdf.
Full textSilva, Marta Uva Cansado Gonçalves. "Clínica e cirurgia de equinos." Master's thesis, Universidade de Évora, 2019. http://hdl.handle.net/10174/25901.
Full textKarlström, Åsa. "Collagen-like proteins in horse pathogenic Streptococcus equi /." Uppsala : Dept. of Microbiology, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/200599.pdf.
Full textLindmark, Hans. "Characterization of adhesive extracellular proteins from Streptococcus equi /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5488-3.pdf.
Full textLibardoni, Felipe. "Equinos portadores de Streptococcus equi subespécie equi: prevalência, fatores de risco e caracterização de alelos seM." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/4105.
Full textA adenite equina é uma doença infecto-contagiosa que acomete o trato respiratório superior, sendo uma das principais doenças respiratórias de equinos. O agente etiológico dessa enfermidade é o Streptococcus equi subespécie equi (S. equi), responsável por aproximadamente 30% das notificações em todo o mundo. Os principais sinais clínicos da adenite são febre, secreção nasal e enfartamento de linfonodos, que ocorre pela dificuldade de fagocitose do S. equi por células de defesa devido a presença da cápsula de ácido hialurônico e proteína M. O entendimento sobre a epidemiologia, a análise de fatores de risco para adenite equina e o controle dessa enfermidade ainda são limitados. Estudos moleculares demonstram diferenças na extremidade 5 da sequência do gene (seM) codificador da proteína M de S. equi. Esta região do gene já foi utilizada na diferenciação de isolados por meio da caracterização de diferentes alelos. Por tudo isso, essa tese objetivou obter resultados de prevalência, e também análise de fatores de risco para adenite equina através de um desenho experimental para coleta de suabes nasais. Foram obtidos 1.010 suabes nasais de equinos sadios em 341 fazendas, de onde foram identificados 24 equinos positivos para S. equi em isolamento, que posteriormente foram confirmados por PCR e sequenciamento de DNA. A prevalência estimada por equino foi de 2.37%, e 20 fazendas foram consideradas positivas (5.86%). Na análise de fatores de risco, foi comprovado e quantificado estatisticamente que: número de eventos de aglomeração que os equinos participam (RR:1.06), o ato de compartilhar recipiente de alimento (RR:3.74) e ter tido diagnóstico positivo para adenite (RR:3.20) são fatores de risco relevantes para adenite equina. Estes resultados oferecem contribuições epidemiológicas importantes para a indústria de equinos e pode apoiar o controle da doença. Em paralelo, a região 5 terminal do gene seM das 24 amostras positivas foi amplificada por PCR e sequenciada para caracterização de alelos, sendo identificado o mesmo alelo (seM-61) em todas as amostras. Esses resultados evidenciam a hipótese de seleção natural de alelos aparentemente mais adaptados a sobreviver, persistir e se perpetuar na população estudada.
West, Douglas Anthony. "In vitro analysis of the role of the Streptococcus equi subspecies equi hyaluronic acid capsule in virulence." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616143.
Full textFreislerová, Eva. "Produkce kyseliny hyaluronové covRS-deficientním kmenem Streptococcus equi subsp. zooepidemicus." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-240561.
Full textLibardoni, Felipe. "Epidemiologia molecular de surtos de Adenite equina no Rio Grande do Sul Brasil." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/10128.
Full textA adenite equina é uma doença infecto-contagiosa que acomete o trato respiratório superior, sendo uma das principais doenças respiratórias de equinos. O agente etiológico dessa enfermidade é o Streptococcus equi subespécie equi (S. equi), responsável por aproximadamente 30% das notificações em todo o mundo. Os principais sinais clínicos da adenite são febre, secreção nasal e enfartamento de linfonodos, que ocorre pela dificuldade de fagocitose do S. equi por células de defesa devido a presença da cápsula de ácido hialurônico e proteína M. Somado a isso, o entendimento sobre a epidemiologia e o controle da adenite equina ainda é limitado. Estudos moleculares demonstram diferenças na região N-terminal na sequência do gene codificador da proteína M (SeM) de S. equi. Esta região do gene já foi utilizada na diferenciação de isolados por meio da caracterização de diferentes alelos. Esta dissertação objetivou analisar e diferenciar 47 isolados bacterianos de S. equi provenientes de amostras clínicas de equinos da região sul do Brasil, oriundas de 15 animais Puro Sangue de Corrida (PSC), 29 da raça Crioula e três da raça Brasileiro de Hipismo (BH), por meio de análise filogenética e diferenciação de alelos, com base no sequenciamento da região Nterminal do gene SeM. As amostras foram oriundas de 31 surtos em 20 estabelecimentos de criação. Foram encontrados 15 alelos de SeM, dentre os quais apenas um (alelo 9) já disponível no banco de dados PubMLST-SeM, como alelo 61, com sete isolados (14,9%). Entre os novos alelos identificados, o alelo 1 foi o mais prevalente com 13 isolados (27,7%), seguido pelo alelo 3 com 10 isolados (21,3%). Os resultados demonstram a grande diversidade da proteína M entre os isolados de S. equi na população equina estudada. Portanto, o sequenciamento parcial do gene da proteína M do S. equi é uma ferramenta útil na investigação epidemiológica para a diferenciação de isolados em surtos de adenite equina, com a identificação de alelos em populações de equinos. Além disso, pode representar uma perspectiva para o controle da enfermidade com a orientação na escolha de cepas para confecção de vacinas comerciais e autógenas.
Becerra, Martínez José Luis Elías. "Obtención de una proteína recombinante PsaA de Streptococcus pneumoniae, homóloga a una de Streptococcus equi." Tesis, Universidad de Chile, 2005. http://repositorio.uchile.cl/handle/2250/130773.
Full textLos streptococos patógenos para los equinos incluyen S. equi subsp. equi (S. equi), S. equi subsp. zooepidemicus, S. dysgalactiae subsp. equisimilis y S. pneumoniae cápsula Tipo III. S. equi causa gurma, una linfoadenitis purulenta altamente contagiosa que afecta a los miembros de la familia Equidae. Rápidos progresos se han realizado para la identificación de factores de virulencia y proteínas de S. equi. La mayoría de éstas son expresadas en la superficie bacteriana o son secretadas. Se ha demostrado la presencia de una proteína homóloga a la pneumococcal surface adhesin A (PsaA) de S. pneumoniae, en S. zooepidemicus y S. equi. La PsaA de S. pneumoniae, como otras proteínas, es inmunogénica y protege animales de laboratorio ante un desafío con neumococos. El objetivo de esta memoria fue obtener desde un aislado clínico de S. pneumoniae, una PsaA recombinante purificada desde E. coli BL21DE3. La metodología consistió en amplificar el gen PsaA por PCR y ligarlo al plasmidio de clonamiento (pETBlue-1), luego con la mezcla de ligación PsaA/pSTBlue-1 se transformó la cepa E. coli DH5; de las colonias transformadas, se purificó el plasmidio (PsaA/pSTBlue-1) por lisis alcalina, el cual fue sometido a digestión doble y, el fragmento liberado, fue ligado finalmente a un vector de expresión (pET-15b). Con la mezcla de ligación PsaA/pET-15b, se transformó la cepa E. coli BL21DE3, que expresó una proteína fusionada a una cola de histidina; la proteína fusionada, a su vez, se purificó en una columna con afinidad por histidina (Ni-Nta). La presencia de rPsaA fue analizada mediante electroforesis en gel de poliacrilamida y por Western blot, observándose la presencia de una proteína de 37 kDa., con la que reaccionó específicamente el anticuerpo policlonal de conejo anti His-tag. La secuencia nucleotídica del fragmento fue comparada en la base de datos BLAST (www.ncbi.nlm.nih.gov), encontrándose un 98% de identidad con la cepa S. pneumoniae R6. Además se identificaron cuatro regiones, con identidades superiores al 80%, similares a las del gen parcial mba de la proteína ligadora de metal/adhesina de S. equi, homóloga a PsaA de S. pneumoniae. El producto obtenido permitirá realizar estudios de formulación y evaluación, en modelo animal, de un prototipo de vacuna contra el gurma, basado en la proteína PsaA de S. pneumoniae.
Heather, Zoe. "Comparative and functional genomic analysis of Streptococcus equi and Streptococcus zooepidemicus : identifying novel vaccine targets." Thesis, Open University, 2009. http://oro.open.ac.uk/54823/.
Full textDelph, Katherine. "Comparison of immunologic responses following intranasal and oral administration of a USDA-approved, live-attenuated Streptococcus equi vaccine." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/32595.
Full textDepartment of Clinical Science
Elizabeth Davis
Background: While there is a commercially-available vaccine for Streptococcus equi subsp. equi licensed for the intranasal route of administration, some equine practitioners are administering this vaccine orally despite a lack of evidence for its efficacy by this route of administration. Objectives: To compare systemic and local immune responses following intranasal or oral administration of the USDA-approved, live-attenuated Streptococcus equi subspecies equi vaccine (Pinnacle IN®, Zoetis, Florham Park, New Jersey). Study Design: Experimental, randomized clinical trial Methods: Eight healthy horses with low Streptococcus equi M protein (SeM) titers (<1:1600) were randomly assigned to an intranasal or oral two-vaccine series. SeM-specific serum immunoglobulins G (IgG) and A (IgA) and nasal secretion IgA were assessed using a commercially-available ELISA (Equine Diagnostic Solutions, LLC, Lexington, Kentucky) and a novel magnetic microsphere assay utilizing fluorescence. A general linear mixed models approach was used for statistical data analysis. Results: As expected, intranasal vaccinates showed substantial increases in both serum SeM-specific IgG and IgA levels post-vaccination (P=0.0006 and P=0.007, respectively). Oral vaccinates showed an increase in serum SeM-specific IgG post-vaccination (P=0.0150), though only one-third the magnitude of intranasal vaccinates. Oral vaccinates showed no evidence of change in SeM-specific IgA post-vaccination (P=0.15). Main Limitations: Changes in mucosal antibody responses were not identified in this study which may be related to small change in antibody response, timing of sample collection, or method of nasal secretion collection. Conclusions: Results indicate that intranasal or oral vaccine administration resulted in increased serum SeM-specific IgG, though the magnitude of response differed between routes.
Hamilton, Andrea. "An investigation of lipoprotein biosynthesis in the equine pathogen Streptococcus equi." Thesis, University of Sunderland, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268974.
Full textSilva, Mariana Sá e. "COMPARAÇÃO ENTRE TESTES BIOQUÍMICOS E ANÁLISE DA SEQUÊNCIA PARCIAL DO GENE hsp60 PARA A IDENTIFICAÇÃO DE ISOLADOS DE Streptococcus equi." Universidade Federal de Santa Maria, 2005. http://repositorio.ufsm.br/handle/1/10217.
Full textStreptococcus equi is the etiological agent of strangles. Opportunistic agents from the same group are frequently isolated from horses with strangles and may induce mistake diagnostic. Among the subspecies of S. equi the phenotypic characteristics are almost undistinguishable; however the pathogenic potential is widely differentiated. The objective of this study was to determine the phenotypic and molecular characteristics of S. equi isolates obtained from samples of clinical cases of strangles by sequencing the hsp60 gene. By phenotypical assays 26 strains of Streptococcus sp. were identified, 18 were characterized as S. equi subsp. equi, five as S. equi subsp. zooepidemicus, two as S. dysgalactiae subsp., equisimilis, and one as Streptococcus sp.; However using molecular characterization, 21 isolates were identified as S. equi subsp. equi and five as S. equi subsp. zooepidemicus. The analysis of the hsp60 sequence is a good discriminatory tool and can be useful as a method of differentiation, principally for the characterization of atypical isolates
Streptococcus equi subesp. equi é o agente etiológico da adenite eqüina. Outros agentes pertencentes ao mesmo grupo, como S. equi subesp. zooepidemicus são freqüentemente isolados de animais com sinais de adenite, podendo originar diagnósticos equivocados. As diferenças bioquímicas são pequenas para as subespécies de S. equi, enquanto o potencial virulento é muito diferenciado, havendo, portanto, necessidade de uma correta diferenciação entre os isolados. O presente trabalho teve como objetivo realizar a comparação fenotípica e molecular de isolados de S. equi, obtidos de casos de adenite eqüina, pela análise de seqüências parciais do gene hsp60. De 26 amostras de Streptococcus sp. analisadas, 18 foram bioquimicamente identificadas como S. equi subesp. equi, cinco como S. equi subesp. zooepidemicus, dois isolados S. dysgalactiae subesp. equisimilis e para um isolado não foi possível determinar a espécie. Pela análise das seqüências, 21 isolados foram identificados como S. equi subesp. equi e cinco como S. equi subesp. zooepidemicus. Dentre os isolados utilizados, quatro apresentaram divergência entre os métodos utilizados. A análise de seqüências do gene hsp60 possui um bom poder discriminatório e pode ser um importante método auxiliar na diferenciação de isolados de Streptococcus equi, especialmente para isolados com padrão atípico de fermentação de açucares
Ribas, Leandro do Monte. "Fatores epidemiológicos associados a doenças respiratórias em potros Puro Sangue Inglês em quatro propriedades na região de Bagé/RS, Brasil." Universidade Federal de Pelotas, 2008. http://repositorio.ufpel.edu.br/handle/ri/2520.
Full textThe present study has the objective to evaluate the epidemiologic factors related to respiratory diseases in thoroughbred foals placed in four stud farms around the city of Bagé/RS region, Brazil. Apart from the collection of data linked to breeding management practices, the evaluations consisted of the diary clinical control and complementary examinations for diagnosis using secretions collected from the respiratory tract of the foals affected with respiratory diseases. Among the 349 monitored foals until their 180 days of life, the incidence of 9,5% (33) of respiratory cases with 0,57% (2) of mortality was recorded. The concentration of cases was higher in months of summer, the 120 and 180 days old foals were more susceptible. The occurrence of the diseases was influenced by the breeding system and management practices that increased the environmental contamination potential, and also by the contact among the foals. No clinic case was related to the equine influenza virus (EIV) and to the equine herpesvirus (EHV) pathogens. Among the isolated pathogens, the highest frequency was for Streptococcus equi (57%), followed by Rhodococcus equi (17%) and this one was responsible for 50% of lethality. The obtained results suggest that connected factors to the management in the breeding of thoroughbred equine are going to contribute decisively for the manifestation of the respiratory disease and alert for the high morbidity caused by the equine adenitis and the high lethality related to Rhodococcus equi pathogens.
O presente estudo teve por objetivo avaliar fatores epidemiológicos associados com doenças respiratórias em potros Puro Sangue Inglês (PSI) alojados em 4 propriedades na região da cidade de Bagé-RS, Brasil. Além da coleta de dados ligados ao manejo de criação, as avaliações consistiram no monitoramento clínico diário e exames complementares de diagnóstico a partir de secreções colhidas do trato respiratório de potros com enfermidade respiratória. Entre os 349 potros monitorados até os 180 dias de vida, pôde-se registrar a incidência de 9,5% (33) de casos respiratórios, com mortalidade de 0,57% (2). A concentração de casos foi mais elevada nos meses de verão e potros com idade entre 120 e 180 dias foram mais suscetíveis. A ocorrência de doenças foi influenciada pelo sistema de criação e práticas de manejo que aumentaram o potencial de contaminação do ambiente e o contato entre potros. Nenhum caso clínico foi relacionado ao vírus da influenza (EIV) e ao herpesvírus eqüino (EHV). Entre os isolados, a maior freqüência foi de Streptococcus equi (57%), seguido do Rhodococcus equi (17%), este responsável pela letalidade de 50%. Os resultados sugerem que fatores ligados ao manejo na criação de eqüinos PSI parecem contribuir decisivamente para a manifestação da doença respiratória e alertam para a elevada morbidade causada pela adenite eqüina e a alta letalidade associada à rodococose entre potros jovens (>180 dias).
Flock, Margareta. "Development of a vaccine against strangles /." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-500-3/.
Full textvon, Beek Christopher. "Interactions of Streptococcus equi and Mast Cells: In the Search of Virulence Factors." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-347561.
Full textKirinus, Jackeline Karsten. "Fenotipia e genotipia de Streptococcus equi isolados de equinos da região sul do Brasil." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/10071.
Full textThe phenotypic characteristics [morphology, biochemical fermentation, antimicrobial susceptibility, index of multiple resistances to antimicrobials (MAR), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of benzilpenicilin] of 38 Streptococcus equi isolates were evaluated in this study. The phenotypic analyses demonstrated three colony patterns, three carbohydrate fermentation patterns and variation from 0 to 0.4 in the index of multiple resistances to antimicrobials. All the isolates of S. equi demonstrated sensitivity to penicillin, both by the disc diffusion method and microdilution method. The average MIC and MBC for benzilpenincillin were of 0,0095 μg/mL and 0.0267 μg/mL for S. equi subsp. equi and of 0.0128 μg/mL and 0.0380 μg/mL for S. equi subsp. zooepidemicus. The samples of S. equi differed in the values of MIC and MBC (p<0,05). The size of the penicillin inhibition halo demonstrated a relation with the MIC and MBC for S. equi subsp. equi, however for the samples of S. equi subsp. zooepidemicus this relation was only verified with the MBC. The MIC of benzilpenincillin of the samples isolated from the Central, Planalto and South regions of Rio Grande do Sul were statistically similar, although different from the Paraná state sample, suggesting the atypical character of this strain. All S. equi isolates are sensitive to penicillin and sulfazotrim, confirming these as antibiotics of choice for the treatment of infections caused by this agent in the clinical veterinary practice. Genotypic characteristics were also analyzed (hsp60 gene partial sequencing and analysis) in 20 isolates of Streptococcus equi from clinical samples of horses with strangles. The phylogenetic analysis showed a politomy among the isolates, suggesting that the hsp60 gene does not allow the differentiation between S. equi subspecies. New studies are suggested with expansion of territory sampled or even with the application of other markers, in order to clarify the evolutionary patterns not resolved and to confirm or not the real genetic differences between subspecies.
As características fenotípicas [morfológicas, bioquímicas, susceptibilidade aos antimicrobianos, índice de resistência múltipla aos antimicrobianos - IRMA, concentração inibitória mínima (CIM), concentração bactericida mínina (CBM) da benzilpenicilina] de 38 isolados de Streptococcus equi foram avaliadas neste estudo. A fenotipia demonstrou três padrões de colônias, três perfis de fermentação de carboidratos e variação de 0 a 0,4 no índice de resistência múltipla aos antimicrobianos. Todos os isolados de S. equi demonstraram sensibilidade à penicilina, tanto pelo método de disco difusão quanto pelo método de microdiluição. A CIM e CBM média de benzilpenicilina foi de 0,0095 μg/mL e 0,0267 μg/mL para S. equi subesp. equi e de 0,0128 μg/mL e 0,0380 μg/mL para S. equi subesp. zooepidemicus. As amostras de S. equi diferiram para valores de CIM e CBM (p<0,05). O diâmetro do halo de inibição de penicilina demonstrou relação com a CIM e a CBM para S. equi subesp. equi, entretanto para as amostras de S. equi subesp. zooepidemicus esta relação somente foi verificada para a CBM. A CIM de benzilpenicilina frente às amostras isoladas da região Central, Planalto e Sul do estado do Rio Grande do Sul foram estatisticamente semelhantes, mas diferiram do isolado do estado do Paraná, sugerindo o caráter atípico desta cepa. Todos os isolados de S. equi são sensíveis à penicilina e sulfazotrim, antimicrobianos de eleição para as afecções por este agente na clínica veterinária. Também foram analisadas as características genotípicas (sequenciamento parcial e análise do gene hsp60) de 20 isolados de Streptococcus equi oriundos de amostras clínicas de animais com adenite equina. A filogenia mostrou uma politomia entre os isolados, e indicou que este marcador (gene hsp60) não permite a diferenciação das subespécies de S. equi. Sugere-se a realização de novos estudos com a ampliação da região amostrada ou mesmo com a aplicação de outros marcadores, a fim de esclarecer os padrões evolutivos não-resolvidos e confirmar ou não a diferenciação genética real entre as subespécies.
Moraes, Carina Martins de. "Produção e avaliação de proteína SeM recombinante para o controle de Adenite Equina." Universidade Federal de Pelotas, 2008. http://repositorio.ufpel.edu.br/handle/ri/1268.
Full textStrangles is a contagious disease of the upper respiratory tract of horses caused by Streptococcus equi subsp. equi. Asymptomatic carriers responsible for maintaining the infection in the herd can only be detected by serological or microbiological methods and vaccines used for the control of the disease induce levels of protection generally not exceeding 50%. Considering that S. equi SeM protein is considered the most promising antigen to protect against the disease, this research aimed to produce and evaluate as antigen for vaccines and for ELISA, a recombinant S. equi SeM protein (rSeM). rSeM was produced by cloning and expression in Escherichia coli and purified by affinity chromatography. To test its immunogenicity isogenic female Balb-c mice 4-6 weeks-old were randomly divided and inoculated with 1 / 20th of the estimated dose of the vaccine for horses by the SC route, on days 0 and 21 of the experiment. One group was vaccinated with 250mL (12 mg mL-1) of rSeM without adjuvant, another with 300mL of vaccine containing 12 mg mL-1 of rSeM plus 20% of aluminiun hydroxide, two other groups were vaccinated with two commercial bacterins against Strangles, other two groups were vaccinated with the same commercial vaccines containing 12 mg mL-1 of rSeM and the remaining group was inoculated with a bacterin produced with a field strain. The control group was inoculated the same dose of sterile saline. Blood samples were collected from the retro-orbital venous plexus on days 0, 21, 42. The antibodies were titrated by ELISA using rSeM as antigen. rSeM was immunogenic for mice with a protection index of 100%. For the standardization of an ELISA, groups of 20 negative, vaccinated and positive animals were used. Using as Cut-off the mean plus two SD of the Optical Densities of the negatives, the test showed 100% sensitivity and specificity.
A Adenite Eqüina é uma enfermidade contagiosa do trato respiratório superior dos eqüídeos causada por Streptococcus equi subesp. equi. Animais portadores assintomáticos responsáveis pela permanência da infecção nos rebanhos só podem ser detectados por métodos microbiológicos ou sorológicos e as vacinas utilizadas no controle da doença induzem níveis de proteção geralmente não superiores a 50 %. Considerando que a proteína SeM de S. equi é o antígeno mais promissor na proteção contra a doença, este trabalho objetivou produzir a proteína SeM recombinante de S. equi, visando sua utilização como antígeno em vacinas e em ELISA. Proteína SeM recombinante (rSeM) foi produzida mediante a clonagem e expressão em Escherichia coli e purificada por cromatografia de afinidade. Para testar sua capacidade imunogênica, vacinas elaboradas com rSeM foram aplicadas a camundongos. Fêmeas Balb/c isogênicas com 4-6 semanas foram divididas aleatoriamente e inoculadas por via SC com 1/20 da dose vacinal estimada para cavalos, nos dias 0 e 21 do experimento. Um grupo foi vacinado com 250 mL (12 mg mL-1) de proteína recombinante sem adjuvante, outro com 300 mL de vacina contendo 12 mg mL-1 rSeM adicionada de 20% de hidróxido de alumínio, outros dois grupos com duas bacterinas comerciais contra Adenite Eqüina; dois grupos com as vacinas comerciais, acrescidas de 12 mg mL-1 de rSeM e o grupo restante com uma bacterina contendo cepas de campo. O grupo controle foi inoculado com o mesmo volume de solução salina estéril. Coletou-se sangue por punção do plexo venoso retro-ocular nos dias 0, 21 e 42. Os anticorpos foram titulados por ELISA utilizando a proteína rSeM como antígeno. A rSeM foi imunogênica em camundongos com índices de proteção de 100%. Para a padronização de um ELISA, utilizaram-se grupos de 20 soros equinos de animais negativos, vacinados e positivos. Utilizando um ponto de corte de média das densidades ópticas dos soros negativos acrescidos de dois desvios padrão, o teste teve 100% de sensibilidade e especificidade.
Ikolo, Felicia. "Characterisation of the PrtM maturase of Streptococcus equi, a proven virulence factor in strangles." Thesis, Northumbria University, 2013. http://nrl.northumbria.ac.uk/15129/.
Full textOsičková, Jana. "Řízení molekulové hmotnosti kyseliny hyaluronové (HA) nastavením specifické rychlosti růstu kultury Streptococcus equi subsp. zooepidemicus." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-295654.
Full textRöhm, Albert. "Untersuchungen zur Wirksamkeit und Verträglichkeit eines Lebendimpfstoffes gegen die Druse - Equilis StrepE (Intervet International, Niederlande) - an trächtigen und laktierenden Stuten sowie an Absetzfohlen /." Berlin : Mbv, 2008. http://d-nb.info/993024130/04.
Full textRebello, Stacey Ann. "Estimation of trimethoprim, sulfamethoxazole, and pentoxifylline concentrations in allantoic fluid of pregnant pony mares with experimentally induced placentitis." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0007221.
Full textTypescript. Title from title page of source document. Document formatted into pages; contains 186 pages. Includes Vita. Includes bibliographical references.
Murchie, Tracy Ann. "Measuring gentamicin and penicillin concentrations in allantoic fluid of pregnant pony mares by in vivo microdialysis." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0004906.
Full textTypescript. Title from title page of source document. Document formatted into pages; contains 152 pages. Includes Vita. Includes bibliographical references.
Roger, François. "Recherches épidémiologiques et microbiologiques sur une maladie émergente du dromadaire (Camelus dromedarius) dans la Corne de l'Afrique : rôles possibles du virus de la peste des petits ruminants (Paramyxoviridae, Morbillivirus) et de "Streptococcus equi subsp. equi"." Montpellier 2, 2000. http://www.theses.fr/2000MON20216.
Full textHrudíková, Radka. "Vytipování a sledování exprese genů ovlivňujících syntézu kyseliny hyaluronové ve streptococcus equi subsp. zooepidemicus pomocí technologie dna čipů a real time PCR." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-432922.
Full textMandawe, John Verfasser], Ulrich [Akademischer Betreuer] [Schwaneberg, and Lars Mathias [Akademischer Betreuer] Blank. "Engineering of hyaluronic acid synthases from Streptococcus equi subsp. zooepidemicus and Pasteurella multocida towards improved HA chain length and titer / John Mandawe ; Ulrich Schwaneberg, Lars Mathias Blank." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1181335272/34.
Full textMandawe, John [Verfasser], Ulrich [Akademischer Betreuer] Schwaneberg, and Lars Mathias [Akademischer Betreuer] Blank. "Engineering of hyaluronic acid synthases from Streptococcus equi subsp. zooepidemicus and Pasteurella multocida towards improved HA chain length and titer / John Mandawe ; Ulrich Schwaneberg, Lars Mathias Blank." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1181335272/34.
Full textSpoerry, Christian. "Streptococcal immunoglobulin degrading enzymes of the IdeS and IgdE family." Doctoral thesis, Umeå universitet, Institutionen för molekylärbiologi (Medicinska fakulteten), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-134552.
Full textHarrington, Dean J., I. C. Sutcliffe, and N. Chanter. "The molecular basis of Streptococcus equi infection and disease." 2002. http://hdl.handle.net/10454/11587.
Full textStreptococcus equi is the aetiological agent of strangles, one of the most prevalent diseases of the horse. The animal suffering and economic burden associated with this disease necessitate effective treatment. Current antibiotic therapy is often ineffective and thus recent attention has focused on vaccine development. A systematic understanding of S. equi virulence, leading to the identification of targets to which protective immunity can be directed, is a prerequisite of the development of such a vaccine. Here, the virulence factors of S. equi are reviewed.
Harrington, Dean J., J. S. Greated, N. Chanter, and I. C. Sutcliffe. "Identification of lipoprotein homologues of pneumococcal PsaA in the equine pathogens Streptococcus equi and Streptococcus zooepidemicus." 2000. http://hdl.handle.net/10454/11589.
Full textStreptococcus equi and Streptococcus zooepidemicus are major etiological agents of upper and lower airway disease in horses. Despite the considerable animal suffering and economic burden associated with these diseases, the factors that contribute to the virulence of these equine pathogens have not been extensively investigated. Here we demonstrate the presence of a homologue of the Streptococcus pneumoniae PsaA protein in both of these equine pathogens. Inhibition of signal peptide processing by the antibiotic globomycin confirmed the lipoprotein nature of the mature proteins, and surface exposure was confirmed by their release from intact cells by mild trypsinolysis.
Project grant 056042 from The Wellcome Trust.
Sutcliffe, I. C., J. Trigg, and Dean J. Harrington. "Identification of methionine-processed HPr in the equine pathogen Streptococcus equi." 2000. http://hdl.handle.net/10454/11591.
Full textUsing preparative electrophoresis, a low molecular weight protein has been partially purified from a cell extract of the equine pathogen Streptococcus equi susp. equi. N-terminal sequence analysis and Western blotting revealed the protein to be HPr, a central component of the phosphoenolpyruvate:sugar phosphotransferase system (PTS). Interestingly, the only form of the HPr protein detected in S. equi was one with the amino-terminal methionine removed, a modification that has previously been associated with surface localization of streptococcal HPr proteins.
Harrington, Dean J., I. C. Sutcliffe, M. Haswell, and S. Dixon. "Surface immunolocalisation of HPr in the equine pathogen Streptococcus equi." 2001. http://hdl.handle.net/10454/3147.
Full textWe have investigated the surface localisation of the phosphotransferase system protein HPr in the equine pathogen Streptococcus equi subsp. equi using immunogold localisation and transmission electron microscopy. Like the LppC acid phosphatase lipoprotein, a reference surface antigen, the S. equi HPR could be clearly detected on the surfaces of intact cells. This study is consistent with previous reports that some streptococcal HPr is cell surface associated and suggests that the extracytoplasmic mobilisation and transfer of phosphate groups by streptococci warrant further investigation.
Dixon, S., M. Haswell, Dean J. Harrington, and I. C. Sutcliffe. "Surface Immunolocalisation of HPr in the Equine Pathogen Streptococcus equi." 2001. http://hdl.handle.net/10454/11588.
Full textWe have investigated the surface localisation of the phosphotransferase system protein HPr in the equine pathogen Streptococcus equi subsp. equi using immunogold localisation and transmission electron microscopy. Like the LppC acid phosphatase lipoprotein, a reference surface antigen, the S. equi HPR could be clearly detected on the surfaces of intact cells. This study is consistent with previous reports that some streptococcal HPr is cell surface associated and suggests that the extracytoplasmic mobilisation and transfer of phosphate groups by streptococci warrant further investigation.
Hamilton, A., Dean J. Harrington, and I. C. Sutcliffe. "Characterization of acid phosphatase activities in the equine pathogen Streptococcus equi." 2000. http://hdl.handle.net/10454/11590.
Full textAcid phosphatases hydrolyse phosphomonoesters at acidic pH in a variety of physiological contexts. The recently defined class C family of acid phosphatases includes the 32 kDa LppC lipoprotein of Streptococcus equisimilis. To define further the distribution of acid phosphatases in the genus Streptococcus we have examined the equine pathogens Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus. Whole cell assays indicated that these organisms possess two acid phosphatases with activity optima at pH 5.0 and pH 6.0-6.5 and that only the former of these was, like LppC, resistant to EDTA. Western blotting with a polyclonal anti-LppC antiserum revealed the presence of a cross-reactive 32 kDa protein in both organisms. The cross-reactive protein in S. equi was shown to be a surface accessible lipoprotein as its processing was inhibited by the antibiotic globomycin and it was released from whole cells by treatment with trypsin. The presence of DNA sequences homologous to the S. equisimilis lppC gene were confirmed by PCR. These data strongly suggest that Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus produce a lipoprotein acid phosphatase homologous to LppC of S. equisimilis.
Meyer-Hamme, Maria Barbara [Verfasser]. "Rhodococcus equi und Streptococcus equi subsp. zooepidemicus aus Nasentupfern und Tracheobronchialsekret von lungenkranken Fohlen / vorgelegt von Maria Barbara Meyer-Hamme." 2004. http://d-nb.info/972250387/34.
Full textFigueiredo, Lara Isabel Martins. "Avaliação da integridade e da actividade de antigénios de Streptococcus Equi encapsulados em lipossomas." Master's thesis, 2010. http://hdl.handle.net/10451/5628.
Full textStreptococcus equi subsp. equi é o agente infeccioso da gurma, doença que permanece como uma das mais dispendiosas e disseminadas por todo o mundo, afectando o tracto respiratório de equídeos. Embora S. equi apresente sensibilidade a alguns antibióticos, a prevenção continua a ser a melhor opção uma vez que este tipo de tratamento revela-se na maioria dos casos ineficaz. Durante o período de recobro os animais desenvolvem uma resposta imune protectora principalmente contra a proteína M-“like” (SeM) antifagocítica associada à parede celular. No entanto, a vacinação de cavalos com bacterinas, extractos de S. equi com adjuvantes e mais recentemente, SeM associada a diferentes adjuvantes, não protege eficazmente os animais da infecção por S. equi. Os antigénios produzidos localmente na nasofaringe desempenham um papel muito importante na resposta imune dos animais contra os antigénios de S. equi, fazendo da mucosa nasal uma via de imunização promissora. Os lipossomas foram já descritos como potentes estimuladores da resposta imune das mucosas. O principal objectivo deste trabalho foi o desenvolvimento e caracterização de lipossomas estáveis encapsulando antigénios de S. equi, e avaliar o seu potencial como veículos de entrega de antigénio pela via nasal através das respostas imunes celular, humoral e das mucosas. Os lipossomas encapsulando S. equi foram preparados pelo método de desidratação – reidratação seguido de extrusão e caracterizados quanto ao tamanho, carga superficial e eficácia de encapsulação. A manutenção da integridade dos antigénios após encapsulação foi confirmada por SDS-PAGE. Os lipossomas assim preparados possuíam potencial zeta positivo, diâmetros médios na ordem dos 0,20 μm e eficiência de encapsulação de cerca de 28%. Após administração intranasal estes lipossomas provocaram resposta imune sistémica, com componente humoral e celular assim como resposta imune ao nível da mucosas das mucosas. Este sistema de veiculação de antigénio é apropriado para imunização nasal uma vez que protege o antigénio de degradação e o apresenta de forma eficaz às células apresentadoras de antigénios. Como alternativa aos lipossomas carregados positivamente, lipossomas com carga superficial negativa foram revestidos com quitosano através de incubação. A influência do quitosano na carga superficial dos lipossomas foi também avaliada.
Streptococcus equi subsp. equi (S. equi) is the causative agent of strangles, which is one of the most costly and widespread infectious diseases, affecting the respiratory tract of Equidae. Although S. equi is sensitive to some antibiotics, prevention is still the best option because antibiotic therapy is often ineffective. During the recovery period, horses develop a protective immune response mostly against the antifagocytic cell wall associated M-like protein SeM. However, horse vaccination with bacterins, adjuvanted S. equi extracts and, more recently, SeM associated to different adjuvants, did not protect animals against infection with S. equi. Locally produced nasopharyngeal antibodies play an important role in the immune response of horses to protein antigens of S. equi, suggesting the nasal mucosa as a promising immunization route. Liposomes have been described as potent stimulators of mucosal immune response. The main purpose of the present work was to develop and characterize stable liposomes encapsulating S. equi antigens, and assess their potential as nasal vaccine delivery vehicle for eliciting specific humoral, mucosal and cellular immune responses. S. equi antigens encapsulated liposomes were prepared by dehydration— rehydration method followed by extrusion and fully characterized for their size, surface charge and encapsulation efficiency. Antigen integrity after encapsulation was confirmed by SDS-PAGE. The developed liposomes possessed +12mV zeta potential, an average vesicle size of 0,20 μm and encapsulation efficiency of ∼28%. Following intranasal administration, S. equi extract formulated in liposomes elicited humoral, mucosal and cellular immune responses. This antigen delivery system presents itself as a potential carrier for nasal immunization protecting the antigen from degradation and efficiently presenting it to the antigen presenting cells. As an alternative to positively charged liposomes, negatively charged liposomes were coated with chitosan by simple incubation method. The influence of mucoadhesive polymer chitosan on surface charge was also assessed.
Hamilton, A., C. Robinson, I. C. Sutcliffe, J. Slater, D. J. Maskell, N. Davis-Poynter, K. Smith, A. S. Waller, and Dean J. Harrington. "Mutation of the Maturase Lipoprotein Attenuates the Virulence of Streptococcus equi to a Greater Extent than Does Loss of General Lipoprotein Lipidation." 2006. http://hdl.handle.net/10454/11575.
Full textStreptococcus equi is the causative agent of strangles, a prevalent and highly contagious disease of horses. Despite the animal suffering and economic burden associated with strangles, little is known about the molecular basis of S. equi virulence. Here we have investigated the contributions of a specific lipoprotein and the general lipoprotein processing pathway to the abilities of S. equi to colonize equine epithelial tissues in vitro and to cause disease in both a mouse model and the natural host in vivo. Colonization of air interface organ cultures after they were inoculated with a mutant strain deficient in the maturase lipoprotein ( prtM138-213, with a deletion of nucleotides 138 to 213) was significantly less than that for cultures infected with wild-type S. equi strain 4047 or a mutant strain that was unable to lipidate preprolipoproteins ( lgt190-685). Moreover, mucus production was significantly greater in both wild-type-infected and lgt190-685-infected organ cultures. Both mutants were significantly attenuated compared with the wild-type strain in a mouse model of strangles, although 2 of 30 mice infected with the lgt190-685 mutant did still exhibit signs of disease. In contrast, only the prtM138-213 mutant was significantly attenuated in a pony infection study, with 0 of 5 infected ponies exhibiting pathological signs of strangles compared with 4 of 4 infected with the wild-type and 3 of 5 infected with the lgt190-685 mutant. We believe that this is the first study to evaluate the contribution of lipoproteins to the virulence of a gram-positive pathogen in its natural host. These data suggest that the PrtM lipoprotein is a potential vaccine candidate, and further investigation of its activity and its substrate(s) are warranted.
Matos, Sandra Cristina Machado de. "Distribuição de exotoxinas em estreptococos dos grupos C e G de Lancefield : comparação entre estirpes responsáveis por infeções no Homem e em animais." Master's thesis, 2013. http://hdl.handle.net/10451/11352.
Full textTem-se verificado que espécies de GCGS de origem animal e do Homem causam doenças semelhantes às observadas para Streptococcus pyogenes(GAS) e partilham alguns fatores de virulência. Um total de 430 estirpes isoladas de infeção no Homem em Portugal entre 1998 e 2010 [S.dysgalactiae subsp. equisimilis (n=418), S.canis (SC) (n=7) e S.equi subsp. zooepidemicus (SESZ) (n=3)] e de origem animal SDSE, SC, SESZ, S. equi subps. equi (SESE) e S. dysgalactiae subsp. dysgalactiae (SDSD) recolhidas em Portugal, Alemanha, Itália e Japão foram caraterizadas por electroforese em campo pulsado (PFGE), tipagem emm e presença de genes das exotoxinas. Os resultados de PFGE mostraram uma distinção entre estirpes de SDSE de origem animal e humana e entre SDSE e SDSD, sugerindo que a capacidade destas espécies causarem infeção em diferentes hospedeiros é limitada. Ao contrário do observado para SC, SESE e SESZ, as poucas estirpes de infeção no Homem foram indistiguiveis das de origem animal. O gene emm foi amplificado em 99,7% das estirpes SDSE de infeção no Homem, mas em apenas 79,6% das de origem animal. Nenhuma relação do tipo emm com a severidade da infeção foi encontrada. Poucas estirpes de SC também amplificaram o gene emm, mas nenhuma isolada do Homem foi tipável. Novos alelos dos genes das exotoxinas foram encontrados: speG, speA, speC, speI, speH, speL, speM, speF, speK, szeN, szeP e szeF. A maioria das estirpes de SDSE e SC amplificaram o speG, sugerindo uma proximidade genética entre estas espécies e GAS. Concluiu-se que os GCGS poderão ser reservatórios de genes de exotoxinas e estreptodornases que são codificados por profagos de GAS e que podem ser transferidos por transferência horizontal. Uma possível transferência de genes cromossomais também foi observada entre GAS e GCGS e entre estirpes de GCGS.
It has been found that both animal and human GCGS species cause similar diseases to those caused by Streptococcus pyogenes(GAS), as well sharing some virulence factors. A total of 430 strains isolated from Human infections in Portugal between 1998 and 2010 [S.dysgalactiae subsp. equisimilis (n=418), S. canis (SC) (n=7) and S.equi subsp. zooepidemicus (SESZ) (n=3)] and animal strains SDSE, SC, SESZ, S. equi subsp. equi (SESE) and S. dysgalactiae subsp. dysglactiae (SDSD) isolated from Portugal, Germany, Italy and Japan were characterized by pulsed-field gel electrophoresis (PFGE), emm typing and tested for the presence of exotoxin coding genes. The PFGE results showed distinction between animal and human SDSE strains, as well as between SDSE and SDSD, suggesting that the ability to cause infection in diferent hosts is limited. In contrast for SC as well as SESZ the few human infection strains were indistinguishable from those of animal infections. The emm gene was found in 99,7% of SDSE strains of Human infections, but only 79,6% of animal SDSE isolates amplified this gene. No relationship of emm type with infection severity was found. Few SC strains also amplified this gene, but none of the human isolates could be emm typed. New alleles of several exotoxin genes were found: speG, speA, speC, speI, speH, speL, speM, speF, speK, szeN, szeP and szeF. Most SDSE and SC strains amplified a speG-like gene, suggesting a genetic proximity between the two species and with GAS. It was concluded that GCGS species may be reservoirs of exotoxins and streptodornases genes, which are encoded by GAS prophages and that can be transferred by horizontal gene transfer. Possible chromosomal gene transfers were also identified between GAS and GCGS as well as between GCGS strains of animal and human origin.
Florindo. "Development of alternative micro and nanoparticulate polymeric systems for mucosal delivery of Streptococcus equi antigens." Doctoral thesis, 2008. http://hdl.handle.net/10451/262.
Full textS. equi is considered the causative agent of strangles, a very contagious disease of the upper respiratory tract of the Equidae. Although S. equi is sensitive to some antibiotics, most of the current treatments are ineffective. During the recovery period, horses develop a protective immune response mostly against the antiphagocytic cell wall-associated M-like protein SeM, which encourages the development of efficient vaccines. The main purpose of this thesis was to develop and characterise stable polymeric particles and study their potential as mucosal S. equi antigens adjuvant. Non-aggregated and easily dispersible micro and nanospheres based on poly-e-caprolactone (PCL) and poly(lactic acid) (PLA) polymers were formulated by the double emulsion (w/o/w) solvent evaporation method and fully characterised. BALB/c monocyte macrophages (cell line J774.1A) were used in toxicity tests and cellular uptake studies. The influence of mucoadhesive polymers (chitosan (CS), glycolchitosan (GCS) and alginate (ALG)) and absorption enhancers (spermine (SP) and oleic acid (OA)) in particle physicochemical characteristics and consequently in the humoral, mucosal and cellular immune responses was as well evaluated. The non-toxic cholera toxin B subunit (CTB) is a potent mucosal adjuvant, and the oligodeoxynuleotide with repeating C and G motives (CpG) can also be used to up-regulate mucosal and cellular immune responses, increasing preferentially the T helper type 1 (Th1) cell activity. Therefore, those adjuvants were co-administrated with soluble antigen and non-modified PLA and PCL particles, in order to assess their eventual synergic effect. Inspite of administration route (i.n. and i.m.), S. equi-loaded polymeric systems were able to significantly increase systemic and cellular immune responses, when compared with free antigens, isolated or co-admixed with CTB or CpG. PLA-loaded particles generally induced higher mucosal antibody levels when compared with the correspondent PCL. Similar results were attained when the immune responses induced by S. equi antigens-adsorbed particles were compared with those elicited by the correspondent entrapped ones. As per PCL nanospheres, those formulated with ALG and GCS, seem to induce a more balance Th1/Th2 immune response. This study also confirmed the potential adjuvant of S. equi antigen-loaded PLA nanospheres, and again the mucopolysaccharide GCS induced the most prominent immune response. SeM recombinant proteins were entrapped in PLA nanospheres and their adjuvant potential after i.m. administration in a mouse model was compared with that achieved with S. equi extract. In fact, it was possible to observe that PLA-GCS and PLA-OA nanospheres are alternative cost-effective preparations, able to induce a balanced IgG2a/IgG1 immune response. These studies bring new insights into the strangles prevention field as the particulate carriers developed during this PhD thesis, mainly those containing GCS, are promising adjuvants for a safe vaccine against strangles, with no toxicity issues associated to their utilisation, in contrast to other adjuvants that have been associated to S. equi antigens. Therefore, the main goal of this thesis was accomplished but challenge studies must be done in order to support their future utilisation.
Fundação para a Ciência e Tecnologia (FCT) e FEDER (SFRH/BD/14370/2003, POCI/BIO/59147/2004 e PPCDT/BIO/59147/2004)
Hou, Chien-meng, and 侯建蒙. "The Effect of Added Agents on Hyaluronic Acid Production by Streptococcus equi subsp. zooepidemicus HAWU." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/13167063671156050919.
Full text大葉大學
生物產業科技學系
98
Hyaluronic acid (HA) is a high molecular-weight polymer with repeating units of D-glucuronic acid and N-acetylglucosamine that are bound by alternating β-1,3 and β-1,4 bonds. Because of it’s special biocompatibility and moister-holding function. It has been used as biomedical, cosmetic industry and else relevance field. Commercially, HA is produced through extraction from rooster combs or by microbial fermentation, but problems with this material include the likelihood of it being contaminated by viruses. The main aim of the research was to determine the effect of added agents on hyaluronic acid production by streptococcus equi subsp. zooepidemicus HAWU. The description of this divided in to third sections. The first section is focused on the effect of added agents (lactic acid, Soya beans extract, H2O2) on the production of HA by S. equi subsp. zooepidemicus HAWU. in the flask and 5-L jas ferentor. In the flask, the optimal temperature was 37℃, which led to highest HA production (4.58 g/L). In a 5-L jar fermentor, we achieved maximum HA productivity (1.0 g/h/L) when the added agents. The second section is focused on the empirical kinetic model for the batch production of HA from S. equi subsp. zooepidemicus HAWU. By using Momod and Michaelis- Meten models, it was found that substrate inhibition for HA production when H2O2 was greater than 1 μmolg/L. Morevorer, a model involved with S. equi subsp. zooepidemicus HAWU growth, and HA accumulation combined non- growth- associated and growth- associated contributions, and consumprion of glucose on the logistic and Luedeking- piret equation was developed. The results predicted by the model were good agreement with the experimental observations. The third section is focused on the potential applications of HA as humectant was also study in this research and, the results show that HA has high moisture-absorption and moisture-retention capacities.
Ikolo, F., M. Zhang, Dean J. Harrington, C. Robinson, A. S. Waller, I. C. Sutcliffe, and G. W. Black. "Characterisation of SEQ0694 (PrsA/PrtM) of Streptococcus equi as a functional peptidyl-prolyl isomerase affecting multiple secreted protein substrates." 2015. http://hdl.handle.net/10454/10324.
Full textPeptidyl-prolyl isomerase (PPIase) lipoproteins have been shown to influence the virulence of a number of Gram-positive bacterial human and animal pathogens, most likely through facilitating the folding of cell envelope and secreted virulence factors. Here, we used a proteomic approach to demonstrate that the Streptococcus equi PPIase SEQ0694 alters the production of multiple secreted proteins, including at least two putative virulence factors (FNE and IdeE2). We demonstrate also that, despite some unusual sequence features, recombinant SEQ0694 and its central parvulin domain are functional PPIases. These data add to our knowledge of the mechanisms by which lipoprotein PPIases contribute to the virulence of streptococcal pathogens.
"Characterization and evaluation of cross reactivity of strains of Streptococcus equi recovered from horses in shouthern Rio Grande do Sul, Brazil." Tese, Biblioteca Digital da Universidade Federal de Pelotas, 2005. http://www.ufpel.edu.br/tede/tde_busca/arquivo.php?codArquivo=247.
Full textHamilton, A., C. Robinson, I. C. Sutcliffe, I. Slater, D. J. Maskell, K. Smith, A. Waller, and Dean J. Harrington. "Mutation of the maturase lipoprotein attenuates the virulence of Streptococcus equi to a greater extent than does loss of general lipoprotein lipidation." 2006. http://hdl.handle.net/10454/3806.
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