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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Příprava myších monoklonálních protilátek proti cyklin-dependentní kináze 13 / Preparation of mouse monoclonal antobodies against cyclin-dependent kinase

Šupák, Marek January 2019 (has links)
The aim of this master‘s thesis is to prepare a monoclonal antibody against cyclin-dependent kinase 13 (CDK13). The theoretical part focuses on antigen-antibody binding, which is essential for the use of monoclonal antibodies in the determination of CDK13 as well as the transcription that this kinase affects. This section is also devoted to Western blot and ELISA methods for detection of newly generated antibodies. Furthermore, the antibodies and the antigen definition are stated, which are later on discussed. The practical part is devoted to the preparation of antigen - its isolation and purification on a peristaltic pump. It also addresses immunization, its course, and the amount of antigen used to immunize mice. After immunization, the work focuses on fusion of sp-2 cells and splenocytes, which were first removed from the immunized mouse and purified. After the fusion alone, selection of hybridomas on HAT selection medium is mentioned, followed by detection first by ELISA and later by Western blotting. The resulting hybridomas with positive ELISA response are frozen for further testing at the Veterinary Research Institute in Brno, where the entire practical part of this thesis was carried out. These frozen hybridomas are further tested by immunoprecipitation to conclude this thesis.
22

Investigation of the auto-ubiquitination and ubiquitination potentials of Retinoblastoma binding protein 6 and its binding to p53

Simons, Taskeen January 2019 (has links)
>Magister Scientiae - MSc / Retinoblastoma Binding Protein 6 (RBBP6) is a 200 kDa human protein known to play an essential role in mRNA 3’-end processing, as well as functioning as an E3 ligase to catalyze ubiquitination and suppression of p53 and other cancer-associated proteins. A RBBP6 knockout mouse model previously suggested that RBBP6 cooperates with MDM2 in polyubiquitinating p53, but is not able to ubiquitinate p53 without the assistance of MDM2. However, unpublished studies from our laboratory suggest that the N-terminal 335 residues of RBBP6, known as R3, are able to ubiquitinate p53 in full in vitro assays, and that the isolated RING finger of RBBP6 is able to catalyse ubiquitination of itself, a phenomenon known as auto-ubiquitination. It is, however, possible that other domains within RBBP6, in particular the ubiquitin-like DWNN domain situated near to the RING finger, may modulate the autoubiquitination and substrate-ubiquitination potentials of the complete protein. / 2022
23

Application of pulse width modulation to a Western blotting device

TruongVo, ThucNhi January 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / One of the critical steps in a current Western blot technique is a blotting process, which in general requires one electrophoretic gel for every protein species to be analyzed. In most cases, multiple protein species are analyzed simultaneously and thus it is necessary for a scientist to run multiple gels. In order to make it possible to analyze multiple protein species from a single gel, a novel blotting device, BlotMan, was employed in this study. Designed by Dr. Chien’s group (YC Bioelectric), BlotMan uses pulse width modulation (PWM) for applying a protein size-dependent voltage during a blotting process. In this study, the differential average voltage profile, depending on protein size (e.g. 17 kDa to 140 kDa), was built and enabled BlotMan to transfer all protein species in equal efficiency regardless of the protein size. Furthermore, Blot- Man consists of a user-friendly, custom-made interface box, which can be remotely controlled by a smart phone. BlotMan’s capability was evaluated using standard protein markers, as well as protein samples that were isolated from chondrosarcoma cells (SW1353) and breast cancer cells (MDA-MB-213). The experimental results revealed that BlotMan was capable of generating 5 blotting membranes from a single gel simultaneously. Protein species such as c-Src, eukaryotic translation initiation factor 2 alpha (eIF2α) and its phosphorylated form (p-eIF2α), lamin B, and β-actin were successfully detected. It is also demonstrated that compared to a regular constant voltage, PWM signals improved transfer efficiency and a signal-to-noise ratio. In conclusion, this study demonstrated that BlotMan was able to facilitate Western blotting analysis by generating multiple blotting membranes from a single gel with an improved signal-to-noise ratio. Further analysis is recommended for understanding the mechanism of PWMts action on transfer efficiency and noise reduction.
24

Caracterização das proteínas do saco vitelínico de embriões bovinos Bos indicus / Characterization of the yolk sac proteins of the Bos indicus bovine embryos

Matsumoto, Fabiana Santos 16 March 2007 (has links)
O saco vitelínico é uma das membranas embrionárias que desempenham um papel importante para a sobrevivência inicial do embrião em muitas espécies de mamíferos, além de produzir proteínas necessárias para o desenvolvimento do mesmo. Foram coletados 17 embriões bovinos, em diferentes períodos gestacionais afim de identificar as proteínas alfafetoproteína, alfa- 1 antitripsina e transferrina, presentes no saco vitelínico destes,para tanto realizou-se a técnica de Western Blot com eletroforese em gel de poliacrilamida, SDS-PAGE a 6%. Os géis, após a corrida, foram corados com Comassie blue, e as membranas de nitrocelulose, após a transferência, com Ponceau. Utilizaram-se os anticorpos monoclonal para alfafetoproteína anti-camundongo, monoclonal, receptpr de transferrin anti-camundongo IgG1, e policlonal para alfa- 1 antitripsina anti-coelho como anticorpos primário e conjugado para peroxidase e fosfatase como secundários. A revelação foi do tipo colorimétrica-fosfatase alcalina e por ECL. O saco vitelínico apresentou-se bem desenvolvido até os 50 dias de gestação, onde, a partir desse período o processo de involução está bem caracterizado Em algumas amostras do saco vitelínico detectamos a presença da alfafetoproteina, alfa-1 antitripsina e da transferrina, porém em algumas amostras as bandas estavam fracas, mostrando assim, que os anticorpos reagem com as proteínas bovinas. O fato de aparecerem bandas fracas pode estar relacionado a uma fraca reação cruzada por se tratar de um anticorpo não específico. / In many species of mammals, the yolk sac is one of the embrionary membranes that plays an important role in the embryo´s initial survival, as well as, in the manufacturing of the necessary proteins for its development. In order to identify the proteins: alfafetoprotein, alfa 1 - antitrypsin, and transferrin present in the cow´s embryo´s yolk sac, 17 bovine embryos were collected in different pregnancy periods. This procedure was performed by Western Blot Technique with a polyacrylamide gel electrophoresis, SDS-PAGE, at 6%. Gels following the electrophoresis, where tainted with Comassie blue, and the membranes of Nitrocellulose, following their transference (the proteins that were present in the gel go to the membrane), with Ponceau. Monoclonal Antibody mouse anti human α-fetoprotein, alphafetoprotein mouse monoclonal antibody, transferrin receptor mouse IgG1, and rabbit polyclonal to alpha 1 antitrypsin were used as primary antibodies, and Peroxidase labelled antimouse e Peroxidase labelled antirabbit e anti-mouse IgG- Alkaline Fosfatase as secundary ones. The membrane´s revelation was of the alcaline fosfatase colormetric type and by ECL. The yolk sac was presented well developed until the 50 days of gestation, where to break of this period the involution process well it is characterized. In some of the yolk sac samples we detected the presence of alfafetoprotein, alfa 1- antitrypsin, and transferrin, however, the bands in some specimens (samples) were weak, demonstrating that the antibodies react with the bovine proteins. The fact that weak bands appeared might be related to a weak cross reaction since we are dealing with a non specific antibody.
25

Identificação de antígenos do carrapato Rhipicephalus (Boophilus) microplus por soros de bovinos geneticamente resistentes e suscetíveis ao parasita / Identification of antigens from the cattle tick, Rhipicephalus (Boophilus) microplus, by sera from genetically resistant and susceptible bovines.

Garcia, Gustavo Rocha 07 May 2009 (has links)
Carrapatos da espécie Rhipicephalus (Boophilus) microplus causam enormes prejuízos à saúde e à produção animal. Sendo um ectoparasita hematófago, o carrapato espolia seu hospedeiro e transmite doenças. Seu parasitismo é mediado por sua saliva, que inibe as reações homeostáticas do hospedeiro à injúria local causada por sua picada. Seus hospedeiros montam respostas imunes contra esse parasita, incluindo a resposta imune mediada por anticorpos, indicando que o controle imunobiológico é possível. Contudo, o complexo farmacológico da saliva do parasita é composto por proteínas solúveis que são sabidamente pouco ou nada imunogênicos se não forem introduzidos no hospedeiro com adjuvante ou na foram agregada. Assim, dificilmente induziriam imunidade nos hospedeiros. Bovinos apresentam fenótipos contrastantes e herdáveis quanto à intensidade de infestações com carrapatos. Carrapatos alimentados em bovinos resistentes não completam a refeição de sangue, apresentando menor eficiência reprodutiva. É possível que esse desfecho seja devido à capacidade do hospedeiro resistente, mas não do suscetível, de produzir anticorpos que neutralizam componentes salivares do carrapato cruciais para realize a hematofagia. É necessário, portanto, examinar essa possibilidade. Os resultados obtidos também podem ajudar a identificar antígenos úteis para formular uma vacina anti-carrapato. Para estabelecer quais componentes salivares são reconhecidos pelos dois fenótipos de hospedeiros empregamos uma soroteca composta por soros obtidos de bovinos resistentes e suscetíveis ao carrapato em diferentes estágios do ciclo do parasito (larva, ninfa e adulto) e após uma, duas ou três ciclos de infestações. Os soros foram empregados individualmente e em forma de pools para imunodetecção por western blot de proteínas presentes em extrato de larvas não-alimentadas, saliva e glândulas salivares de fêmeas de R. microplus e separadas em uma e duas dimensões. Os resultados obtidos nos western blots 1D de saliva e de extrato de larvas não alimentadas mostraram que houve um reconhecimento diferencial dos antígenos parasitários pelos soros dos animais resistentes e suscetíveis. Os soros dos animais resistentes quando ainda eram livres de infestações (i.e., naïve) ou quando infestados com a forma larval reconheceram com maior freqüência e/ou exclusivamente certas bandas de proteínas. Resultados semelhantes foram vistos nos western blots de géis 2D de saliva e glândulas salivares de fêmeas, onde os soros dos animais resistentes ainda não infestados (i.e., naïve) reconheceram vários spots presentes nessas amostras e soros de animais resistentes infestados reconhecerem spots de forma exclusiva. Também foi observado que, apesar dos hospedeiros suscetíveis estarem expostos a grande quantidade de saliva, os soros desses animais não reconhecem um número maior de spots que os hospedeiros infestados resistentes. Por outro lado, a maioria das proteínas salivares não é reconhecida pelos hospedeiros infestados, sejam resistentes ou suscetíveis. Esses resultados indicam que os hospedeiros bovinos resistentes reconhecem de forma mais precoce que os bovinos suscetíveis certos componentes parasitários. Essa capacidade pode estar relacionada ao fenótipo de resistência ao carrapato / The cattle tick, Rhipicephalus (Boophilus) microplus, causes enormous losses to animal health and production. Since it is a hematophagous parasite the tick expoliates its hosts and transmits diseases. Parasitism by the tick is mediated by its saliva, which inhibits the hosts local homeostatic reactions to its bite. Hosts mount immune responses against this parasite, including antibody-mediated responses, indicating that the immunobiological control of ticks is possible. However, the pharmacological complex of saliva is composed of soluble proteins, which are known to be incapable of eliciting antibody responses if they are not introduced into the host with adjuvant or in aggregated form. Thus, salivary proteins may not be able to induce immunity in hosts. Bovines present contrasting, heritable phenotypes for tick infestations. Ticks fed on resistant hosts are unable to complete a blood meal and present a decrease in reproductive immunity. It is possible that this outcome is caused by an ability of the resistant host to produce antibodies that neutralize salivary components that are crucial to blood feeding. It is necessary, therefore, to examine this possibility. The results will also assist in the identification of protective antigens to formulate an anti-tick vaccine. In order to establish which salivary components are recognized by the two types of host phenotypes, a collection of sera derived from resistant and susceptible bovines infested one, two and three times with different developmental stages of the parasite (larvae, nymphs and adults) was employed to detect which proteins were recognized in western blots of saliva and extracts of salivary glands and unfed larvae. Western blots of tick proteins (saliva and extracts of unfed larvae) separated in one dimension showed that antigens were differentially recognized by resistant and susceptible bovines. Sera from resistant bovines still naïve or infested with larvae recognized certain protein bands exclusively or more frequently than similar sera from susceptible bovines. Similar results were seen in western blots of proteins from saliva and extracts of salivary glands separated in two dimensions, where sera from naïve, resistant bovines recognized several spots and sera from infested, resistant bovines recognized several spots exclusively. In spite of the fac that susceptible hosts are exposed to greater amounts of tick saliva, sera from these animals did not recognize a greater amount of spots than those from resistant bovines. On the other hand, the great majority of spots is not recognized by any of the different sera, be they from resistant or susceptible hosts. These results indicate that resistant bovines are able to recognize parasitic proteins earlier than susceptible bovines. This ability may, in turn, affect expression of salivary components that are crucial for the tick and may explain the phenotypes of tick infestations in bovines.
26

Efeito do tempo de tratamento e da dose de fluoreto administrada cronicamente na expressão proteica em fígado de ratos

Pereira, Heloisa Aparecida Barbosa da Silva 18 December 2015 (has links)
Submitted by Luciana Sebin (lusebin@ufscar.br) on 2016-09-19T12:55:56Z No. of bitstreams: 1 TeseHABSP.pdf: 4918857 bytes, checksum: fde7822ef1d8c23c0e0c60d9ccaf8152 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-20T18:13:37Z (GMT) No. of bitstreams: 1 TeseHABSP.pdf: 4918857 bytes, checksum: fde7822ef1d8c23c0e0c60d9ccaf8152 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-20T18:13:44Z (GMT) No. of bitstreams: 1 TeseHABSP.pdf: 4918857 bytes, checksum: fde7822ef1d8c23c0e0c60d9ccaf8152 (MD5) / Made available in DSpace on 2016-09-20T18:13:53Z (GMT). No. of bitstreams: 1 TeseHABSP.pdf: 4918857 bytes, checksum: fde7822ef1d8c23c0e0c60d9ccaf8152 (MD5) Previous issue date: 2015-12-18 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / In a previous study conducted by our group, it was noticed that fluoride (F) can induce changes in the expression of several liver proteins. Reports in the literature suggest that the changes caused by F in the body are dose- and time-dependent. The objective of this study was to analyze the effect of different F concentrations, exposure time to this ion and concomitant exposure to a high calorie diet in the metabolism of lipids and protein expression in the liver of rats. The study was divided into 2 steps. The first step included 72 21-day-old male Wistar rats that were divided into 2 groups (n=36) according to the diet administered (AIN-93M and Presence). Each group was further divided according to the duration of the treatment (20 or 60 days). In addition, each these was divided into 3 subgroups (n=6), according to the concentration of F administrated in the drinking water, as follows: 0 mg/L (control), 15 mg/L or 50 mg/L. After the experimental period, the animals were anesthetized and the liver and blood were collected. F analysis in plasma and liver tissue was done. Part of the liver was fixed for histological analysis. Lipids were analyzed in plasma and triglycerides were analyzed in the liver. Expressions of proteins were evaluated in the liver by Western blotting. In the second step the only Presence diet were use and the groups experimental the same as previously described. At the end of experimental period, liver and plasma were collected. F concentration in plasma and liver were analyzed. Liver proteins were extracted and prepared for mass spectrometry analysis. Proteins were sequenced and identified. The analysis of F concentrations indicated a doseresponse increase in plasma, regardless the time of exposure to F and type of diet. F concentrations in the liver were higher in the groups receiving 50 ppm F in respect to control. Administration of F altered the lipid profile, with a reduction in TGA in plasma and increase in HDL when the hypercaloric diet was used. The expression of GRP78, ERP29 and SOD2 and Apo-E was altered by F, under the influence of time and type of diet administered. For the groups receiving 50 mgF/L, it was observed an increase in the concentration of proteins related to the defense against oxidative stress and ER stress. For the group that received the concentration of 15 mgF/L, changes in structural proteins, mitochondrial proteins and proteins related to cell proliferation were observed, depending on the time of administration. The results suggest an adaptive mechanism of liver upon exposure to F, which seems to be related to the activation of proteins related to maintenance of homeostasis and that fight against oxidative stress and ER stress caused by this ion. / Em trabalho prévio realizado pelo nosso grupo foi observado que o fluoreto (F) pode provocar alterações na expressão de várias proteínas hepáticas. Relatos na literatura sugerem que as alterações causadas pelo F no organismo são dose e tempo-dependentes. Assim, o objetivo deste trabalho foi analisar o efeito da administração de diferentes concentrações de F, do tempo de exposição a este íon e da exposição concomitante a uma dieta hipercalórica no metabolismo de lipídios e expressão de proteínas hepáticas em ratos. O trabalho foi realizado em 2 etapas. Na primeira, foram utilizados 72 ratos Wistar machos com 21 dias, que foram divididos em 2 grupos (n=36) de acordo com o tipo de dieta (AIN-93M ou Presence), então subdividido em 2 grupos (n=18) de acordo com o tempo de tratamento (20 ou 60 dias). Cada grupo foi dividido em 3 subgrupos (n=6), de acordo com a dose de fluoreto a ser administrada através da água de beber, a saber: 0 mg/L, 15 mg/L ou 50 mg/L. Decorridos os períodos experimentais o fígado e o sangue foram coletados. Foi realizada a análise de F no plasma e tecido hepático. Parte do fígado foi fixado para a confecção das lâminas para análise histológica. No plasma foi realizada a análise de perfil lipídico e no fígado, de triglicerídeos. Foi avaliada a expressão das proteínas hepáticas por Western Blotting. Na segunda etapa foi realizada apenas com a ração presence com os mesmos grupos experimentais da primeira etapa. Ao final do período experimental, o fígado e o plasma foram coletados. A concentração de F no plasma e no fígado foram analisada. Foi realizada a extração de proteínas e preparação das proteínas do fígado para espectrometria de massa, sendo então sequenciadas e identificadas. A análise das concentrações de F indicaram um aumento dose-resposta no plasma, independente do período administrado ou tipo de dieta. Já as concentrações de F no fígado foram maiores nos grupos que receberam 50 mg/L de F em relação ao controle. A administração de F alterou o perfil lipídico, com uma redução no TGA no plasma e aumento do HDL. As inclusões lipídicas no fígado foram reduzidas no grupo que recebeu 50 ppm F por 20 dias em conjunto com a dieta hipercalórica. A expressão da GRP78, ERP29, SOD2 e Apo-E foram alteradas pelo F, sob influência do tempo e dieta administrada. Para os grupos que receberam a concentração de 50 ppm F foi observado um aumento na concentração de proteínas relacionadas à a defesa contra o estresse oxidativo e do RE. Para o grupo que recebeu a concentração de 15 ppm F houve alterações estruturais, mitocondriais e relacionadas à proliferação, verificando-se um efeito depende do tempo. Desta forma, podemos concluir que o fígado possui um mecanismo de adaptação à ação do F e que o mesmo parece estar relacionado ao acionamento de proteínas referentes à homeostasia e contra o estresse oxidativo e do RE provocado por este íon. / FAPESP: 2011/17263-9
27

Identificação de antígenos do carrapato Rhipicephalus (Boophilus) microplus por soros de bovinos geneticamente resistentes e suscetíveis ao parasita / Identification of antigens from the cattle tick, Rhipicephalus (Boophilus) microplus, by sera from genetically resistant and susceptible bovines.

Gustavo Rocha Garcia 07 May 2009 (has links)
Carrapatos da espécie Rhipicephalus (Boophilus) microplus causam enormes prejuízos à saúde e à produção animal. Sendo um ectoparasita hematófago, o carrapato espolia seu hospedeiro e transmite doenças. Seu parasitismo é mediado por sua saliva, que inibe as reações homeostáticas do hospedeiro à injúria local causada por sua picada. Seus hospedeiros montam respostas imunes contra esse parasita, incluindo a resposta imune mediada por anticorpos, indicando que o controle imunobiológico é possível. Contudo, o complexo farmacológico da saliva do parasita é composto por proteínas solúveis que são sabidamente pouco ou nada imunogênicos se não forem introduzidos no hospedeiro com adjuvante ou na foram agregada. Assim, dificilmente induziriam imunidade nos hospedeiros. Bovinos apresentam fenótipos contrastantes e herdáveis quanto à intensidade de infestações com carrapatos. Carrapatos alimentados em bovinos resistentes não completam a refeição de sangue, apresentando menor eficiência reprodutiva. É possível que esse desfecho seja devido à capacidade do hospedeiro resistente, mas não do suscetível, de produzir anticorpos que neutralizam componentes salivares do carrapato cruciais para realize a hematofagia. É necessário, portanto, examinar essa possibilidade. Os resultados obtidos também podem ajudar a identificar antígenos úteis para formular uma vacina anti-carrapato. Para estabelecer quais componentes salivares são reconhecidos pelos dois fenótipos de hospedeiros empregamos uma soroteca composta por soros obtidos de bovinos resistentes e suscetíveis ao carrapato em diferentes estágios do ciclo do parasito (larva, ninfa e adulto) e após uma, duas ou três ciclos de infestações. Os soros foram empregados individualmente e em forma de pools para imunodetecção por western blot de proteínas presentes em extrato de larvas não-alimentadas, saliva e glândulas salivares de fêmeas de R. microplus e separadas em uma e duas dimensões. Os resultados obtidos nos western blots 1D de saliva e de extrato de larvas não alimentadas mostraram que houve um reconhecimento diferencial dos antígenos parasitários pelos soros dos animais resistentes e suscetíveis. Os soros dos animais resistentes quando ainda eram livres de infestações (i.e., naïve) ou quando infestados com a forma larval reconheceram com maior freqüência e/ou exclusivamente certas bandas de proteínas. Resultados semelhantes foram vistos nos western blots de géis 2D de saliva e glândulas salivares de fêmeas, onde os soros dos animais resistentes ainda não infestados (i.e., naïve) reconheceram vários spots presentes nessas amostras e soros de animais resistentes infestados reconhecerem spots de forma exclusiva. Também foi observado que, apesar dos hospedeiros suscetíveis estarem expostos a grande quantidade de saliva, os soros desses animais não reconhecem um número maior de spots que os hospedeiros infestados resistentes. Por outro lado, a maioria das proteínas salivares não é reconhecida pelos hospedeiros infestados, sejam resistentes ou suscetíveis. Esses resultados indicam que os hospedeiros bovinos resistentes reconhecem de forma mais precoce que os bovinos suscetíveis certos componentes parasitários. Essa capacidade pode estar relacionada ao fenótipo de resistência ao carrapato / The cattle tick, Rhipicephalus (Boophilus) microplus, causes enormous losses to animal health and production. Since it is a hematophagous parasite the tick expoliates its hosts and transmits diseases. Parasitism by the tick is mediated by its saliva, which inhibits the hosts local homeostatic reactions to its bite. Hosts mount immune responses against this parasite, including antibody-mediated responses, indicating that the immunobiological control of ticks is possible. However, the pharmacological complex of saliva is composed of soluble proteins, which are known to be incapable of eliciting antibody responses if they are not introduced into the host with adjuvant or in aggregated form. Thus, salivary proteins may not be able to induce immunity in hosts. Bovines present contrasting, heritable phenotypes for tick infestations. Ticks fed on resistant hosts are unable to complete a blood meal and present a decrease in reproductive immunity. It is possible that this outcome is caused by an ability of the resistant host to produce antibodies that neutralize salivary components that are crucial to blood feeding. It is necessary, therefore, to examine this possibility. The results will also assist in the identification of protective antigens to formulate an anti-tick vaccine. In order to establish which salivary components are recognized by the two types of host phenotypes, a collection of sera derived from resistant and susceptible bovines infested one, two and three times with different developmental stages of the parasite (larvae, nymphs and adults) was employed to detect which proteins were recognized in western blots of saliva and extracts of salivary glands and unfed larvae. Western blots of tick proteins (saliva and extracts of unfed larvae) separated in one dimension showed that antigens were differentially recognized by resistant and susceptible bovines. Sera from resistant bovines still naïve or infested with larvae recognized certain protein bands exclusively or more frequently than similar sera from susceptible bovines. Similar results were seen in western blots of proteins from saliva and extracts of salivary glands separated in two dimensions, where sera from naïve, resistant bovines recognized several spots and sera from infested, resistant bovines recognized several spots exclusively. In spite of the fac that susceptible hosts are exposed to greater amounts of tick saliva, sera from these animals did not recognize a greater amount of spots than those from resistant bovines. On the other hand, the great majority of spots is not recognized by any of the different sera, be they from resistant or susceptible hosts. These results indicate that resistant bovines are able to recognize parasitic proteins earlier than susceptible bovines. This ability may, in turn, affect expression of salivary components that are crucial for the tick and may explain the phenotypes of tick infestations in bovines.
28

Caracterização das proteínas do saco vitelínico de embriões bovinos Bos indicus / Characterization of the yolk sac proteins of the Bos indicus bovine embryos

Fabiana Santos Matsumoto 16 March 2007 (has links)
O saco vitelínico é uma das membranas embrionárias que desempenham um papel importante para a sobrevivência inicial do embrião em muitas espécies de mamíferos, além de produzir proteínas necessárias para o desenvolvimento do mesmo. Foram coletados 17 embriões bovinos, em diferentes períodos gestacionais afim de identificar as proteínas alfafetoproteína, alfa- 1 antitripsina e transferrina, presentes no saco vitelínico destes,para tanto realizou-se a técnica de Western Blot com eletroforese em gel de poliacrilamida, SDS-PAGE a 6%. Os géis, após a corrida, foram corados com Comassie blue, e as membranas de nitrocelulose, após a transferência, com Ponceau. Utilizaram-se os anticorpos monoclonal para alfafetoproteína anti-camundongo, monoclonal, receptpr de transferrin anti-camundongo IgG1, e policlonal para alfa- 1 antitripsina anti-coelho como anticorpos primário e conjugado para peroxidase e fosfatase como secundários. A revelação foi do tipo colorimétrica-fosfatase alcalina e por ECL. O saco vitelínico apresentou-se bem desenvolvido até os 50 dias de gestação, onde, a partir desse período o processo de involução está bem caracterizado Em algumas amostras do saco vitelínico detectamos a presença da alfafetoproteina, alfa-1 antitripsina e da transferrina, porém em algumas amostras as bandas estavam fracas, mostrando assim, que os anticorpos reagem com as proteínas bovinas. O fato de aparecerem bandas fracas pode estar relacionado a uma fraca reação cruzada por se tratar de um anticorpo não específico. / In many species of mammals, the yolk sac is one of the embrionary membranes that plays an important role in the embryo´s initial survival, as well as, in the manufacturing of the necessary proteins for its development. In order to identify the proteins: alfafetoprotein, alfa 1 - antitrypsin, and transferrin present in the cow´s embryo´s yolk sac, 17 bovine embryos were collected in different pregnancy periods. This procedure was performed by Western Blot Technique with a polyacrylamide gel electrophoresis, SDS-PAGE, at 6%. Gels following the electrophoresis, where tainted with Comassie blue, and the membranes of Nitrocellulose, following their transference (the proteins that were present in the gel go to the membrane), with Ponceau. Monoclonal Antibody mouse anti human α-fetoprotein, alphafetoprotein mouse monoclonal antibody, transferrin receptor mouse IgG1, and rabbit polyclonal to alpha 1 antitrypsin were used as primary antibodies, and Peroxidase labelled antimouse e Peroxidase labelled antirabbit e anti-mouse IgG- Alkaline Fosfatase as secundary ones. The membrane´s revelation was of the alcaline fosfatase colormetric type and by ECL. The yolk sac was presented well developed until the 50 days of gestation, where to break of this period the involution process well it is characterized. In some of the yolk sac samples we detected the presence of alfafetoprotein, alfa 1- antitrypsin, and transferrin, however, the bands in some specimens (samples) were weak, demonstrating that the antibodies react with the bovine proteins. The fact that weak bands appeared might be related to a weak cross reaction since we are dealing with a non specific antibody.
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Avaliação do uso de teste treponêmico imunoenzimático competitivo na triagem sorológica da sífilis em 23.531 soros de uma população de baixa prevalência / Assessment of a Treponemal Competitive Enzyme Immunoassay for Syphilis Antibody Screening in 23,531 Serum Samples from a Low Prevalence Population.

Bazzo, Maria Luiza 30 September 1999 (has links)
Foram testadas, com o teste não treponêmico VDRL e com o teste treponêmico imunoenzimático de competição, 23.531 amostras de soros, coletados em todas as regiões do Brasil, com o objetivo de verificar o comportamento do teste imunoenzimático treponêmico na triagem de amostras. A prevalência obtida foi de 0,63% com o VDRL e de 0,84% para o teste imunoenzimático. A análise dos dados foi feita comparando-se os resultados dos dois testes com os resultados do teste treponêmico de imunofluorescência indireta (FTA-ABS), considerado como teste de referência. No total, 1120 amostras foram submetidas ao teste FTA-ABS, incluindo todas as que foram reagentes em qualquer um dos testes de triagem e 872 amostras negativas. Amostras com resultados discordantes entre os testes foram submetidas a um teste imunoenzimático do tipo Western blot. Nas amostras por nós estudadas, o teste imunoenzimático apresentou sensibilidade de 89,95% e especificidade de 99,78%, muito superior aos 55,11% de sensibilidade e 97,43% de especificidade que encontramos para o VDRL. Os resultados dos testes detectaram positividade em amostras diferentes portanto, recomendamos utilizar a associação dos dois testes, como método de triagem, quando se trata de populações de baixa prevalência. Resultados preliminares do Western blot sugerem a participação doas proteínas de 43 kD, 17 kD e 15,5 kD na reação de ELISA treponêmico competitivo. / The VDRL, a non treponemal test, and a treponemal competitive ELISA were used to test 23,531 serum samples, collected from conscript men throughout Brazil, with the objective of assessing the performance of the competitive ELISA on the screening of serum samples. The VDRL showed a prevalence of 0.63% contrasting with a 0.84% prevalence showed by the competitive ELISA. The results obtained with the two tests were then compared to those obtained by fluorescent treponemal antibody absorption (FTA-ABS) test which is considered the gold standard method for detection of antibodies for syphilis. A total number of 1,120 samples, which included all that were reagent in at least one of the screening test plus 872 that were negative in both tests, were submitted to the FTA_ABS test. In addition, some of the samples that presented discrepant results between the two tests studied were also submitted to the Western blot test. The results of the screening tests showed an 89.95% sensitivity and a 99.78% specificity for the competitive ELISA, which are much higher than the 55.11% sensitivity and 97.43% specificity presented by the VDRL. Also, the tests detected positivity in different samples. In conclusion, we recommended the use in tandem of both tests as screening for syphilis antibodies in low prevalence populations. In addition, the results of the Western blot seemed to suggest the positivity of the ELISA becoming non reactive after treatment of the patient and that the 43 kD, 17 kD and 15 kD proteins are the main proteins involved in the ELISA competitive reaction.
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Caractérisation des agents infectieux responsables de deux maladies à prion : l'ESB atypique de type H chez les bovins et la tremblante de type "CH1641" chez les petits ruminants / Characterization of infectious agents responsible of two different prion disease : the CH1641 scrapie for small ruminants and the atypical H-type BSE for bovine

Vulin, Johann 02 November 2011 (has links)
Nous avons entrepris la caractérisation de la protéine prion pathologique par Western blot à partir d’isolats de petits ruminants et de bovins atteints d’Encéphalopathie Spongiforme Subaiguë Transmissible (ESST) afin d’identifier des signatures moléculaires divergeant de la signature associée à l’ESST affectant habituellement ces animaux ; la tremblante classique pour les petits ruminants et l’ESB classique (ESB-C) pour les bovins. Cette étude a permis d’évaluer la fréquence de phénotypes inhabituels et a contribué à envisager les formes d’ESB atypiques comme sporadiques. Ensuite la transmission des isolats de petits ruminants aux souris C57Bl/6 et TgOvPrP4 a permis d’une part de confirmer l’absence de contamination par l’agent de l’ESB, tout du moins pour les ovins, et d’autre part d’approfondir les connaissances sur la diversité des souches dans les isolats de tremblante. Les travaux de transmission aux souris C57Bl/6 des isolats bovins atteints d’ESB-H ont quant à eux conduit à la description de l’émergence d’une souche présentant les caractéristiques de l’ESB-C suggérant que la forme sporadique d’ESB-H puisse être à l’origine de la contamination initiale des bovins ayant conduit après recyclage par le biais des farines de viande et d’os à l’épizootie d’ESB-C / Molecular characterization using Western blot method has been carried out to identify unusual PrPres pattern from small ruminants and bovines TSE affected. Such analyse allow us to define the frequency of these unusual signature and contribute to consider BSE-H as sporadic form of ruminant TSE. Transmission studies from unusual sheep isolates in C57Bl/6 and TgovPrP4 mice firstly contribute to confirm that none of these sheep isolates was infected by BSE transmission. Secondly, strain characteristics observed through experimental transmission of unusual isolates and classical scrapie affected isolates show results that give some element about strain diversity in both scrapie types. Serial passages of H-BSE in C57Bl/6 mice show the emergence of a prion strain with features similar to classical BSE. Such findings might help to explain the origin of the classical BSE epizootic disease, which could have originated from this kind of sporadic form of BSE

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