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Di, Sarno Veronica. "Design and synthesis of modulators of apoptotic activity." Doctoral thesis, Universita degli studi di Salerno, 2016. http://hdl.handle.net/10556/2229.
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2014 - 2015<br>p53 is a transcription factor with tumour suppressor properties, which is able to induce mitochondrial apoptosis independently of its transcriptional activity. Analogues of the spiro[imidazo[1,5-c] thiazole-3,3′-indoline] -2′,5,7(6H,7aH) -trione, previously synthesized from my research group, as p53 modulators were synthesized during my PhD, aiming to explore new structural requirements at the thiazolidine domain to increase the antiproliferative activity and improve p53 modulation. Derivative 5-bromo-3′- (cyclohexane carbonyl) -1-methyl-2oxospiro[indoline-3,2′-thiazolidine] (SM13) emerged as the most potent compound of all series, inhibiting, in vitro, 30% of p53−MDM2 interaction at 5 μM and the cell growth of different human tumor cells at nanomolar concentrations... [edited by author]<br>XIV n.s.
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Lam, Wing See. "THE ISOLATION AND CHARACTERIZATION OF ARABIDOPSIS AtSMC1 AND AtSMC3." Miami University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=miami1092170063.
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Lopes, Wagner. "Estudo estrutural e funcional das proteínas ligadoras de ácidos graxos (FABP- Fatty Acid Binding Proteins) de Fasciola hepatica." Universidade do Estado do Rio de Janeiro, 2011. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=5921.
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As proteínas ligadoras de ácidos graxos (Fatty Acid Binding Proteins, FABPs) de parasitos têm um papel importante no processo de infecção por estes organismos. Por este motivo, estas proteínas são antígenos candidatos para vacina contra a infecção por Schistosoma mansoni e Fasciola hepatica. No presente trabalho foram caracterizadas FABPs de F. hepatica e comparadas com a proteína Sm14 de S. mansoni, a FABP de parasito melhor caracterizada, mediante análise de sequências e estruturas modeladas. Também foram clonadas, expressas e purificadas as FABPs tipo 1 e tipo 3 de F. hepatica. Os resultados do presente estudo indicam que a FABP tipo 3 de F. hepatica é relacionada estrutural, imunológica e funcionalmente com a Sm14, um candidato vacinal amplamente estudado. Devido à importância da Sm14 como alvo para o desenvolvimento de vacina para a esquistossomose, as características apresentadas pela FhFABP3 de F. hepatica apontam esta proteína como um candidato importante também para o desenvolvimento de uma vacina contra a fasciolose<br>Parasites fatty acid binding proteins (FABPs) have an important role in infection process by these organisms. For this reason, these proteins are candidates as vaccine antigens against Schistosoma mansoni and Fasciola hepatica infection. In the present study, FABPs from F. hepatica were characterized and compared with Sm14 protein from S. mansoni, the best characterized parasite FABP, by sequence analysis and modeled structure. Type 1 and type 3 FABPs from F. hepatica were also cloned, expressed and purified. The results of this study indicated that type 3 FABP from F. hepatica is structural, immunological and functionally related with Sm14, a vaccine candidate widely studied. Due to the importance of Sm14 as a target for vaccine development for schistosomiasis, the characteristics presented by the FhFABP3 from F. hepatica suggest this protein as a candidate also important for the development of a vaccine against fasciolosis
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Espíndola, Milena Sobral. "Avaliação de estratégias de vacinação \"prime-boost\" na infecção experimental por Schistosoma mansoni empregando vacinas de DNA." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/17/17147/tde-02062011-105929/.
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A esquistossomose é uma das mais relevantes doenças induzidas por helmintos, acometendo cerca de 207 milhões de pessoas em todo o mundo. O Praziquantel e o Oxamniquine são os fármacos empregados no tratamento, mas além de não impedirem re-infecções, não atuam nos estágios imaturos do verme. Portanto, o desenvolvimento de uma estratégia de vacinação eficaz representa um componente essencial para o controle e erradicação desta doença. Neste sentido, tivemos como objetivo estudar a resposta imunológica induzida pela imunização com a vacina DNA-Sm14 em associação com a DNA-Hsp65 utilizando protocolos de imunização prime-boost, sendo eles heterólogo ou homólogo. A utilização das vacinas em prime-boost heterólogo não alterou a produção de IgG2a, mas diminuiu a produção de IFN- e IL-10 dos animais quando comparados aos que receberam apenas DNA-Sm14. Após infecção, a estratégia prime-boost heterólogo não foi eficaz em reduzir a carga parasitária dos animais, enquanto a vacinação com DNA-Sm14 reduziu parcialmente o número de vermes. Na vacinação prime-boost homóloga utilizando as duas vacinas, observamos que a modificação da estratégia também não alterou a produção de IgG2a, mas reduziu a produção de IFN- pelas células recuperadas do espaço bronco-alveolar, quando comparada com os animais que receberam DNA-Sm14. Após infecção, a imunização com DNA-Sm14/DNA-Hsp65 não alterou a carga parasitária dos animais, mas sistemicamente reduziu o número de eosinófilos. Quando avaliado o perfil de células de memória dos animais vacinados, verificamos aumento do número de células T CD8+ e menor número de células T CD4+ no baço dos animais imunizados com as duas vacinas simultaneamente. Em suma, a utilização das vacinas DNA-Sm14 e DNA-Hsp65 nas estratégias prime-boost heterólogo ou homólogo não foi capaz de gerar proteção contra infecção experimental por S. mansoni, e sugerimos que em parte, a diminuição de IFN-, IL-10, aumento da razão IgG1/IgG2a e a estimulação de células T CD8+ ao invés de CD4+, podem ter contribuído para baixa eficácia dos protocolos vacinais testados.<br>Schistosomiasis is one of the most important diseases due to helminthes, affecting approximately 207 million people worldwide. The treatment is based on Praziquantel and Oxamniquine drugs, however these drugs do not avoid reinfections and are inefficient against worm immature stages. Therefore, the development of an efficient vaccination strategy is an essential component in the control of this disease. The aim of this work was to study the immune response induced by immunization with DNA-Sm14 vaccine in combination with DNA-Hsp65 using prime-boost protocols, which were heterologous or homologous. The heterologous prime-boost vaccination did not modify IgG2a production, but decreased IFN- and IL-10 production compared to animals that received only DNA-Sm14. After infection, this prime-boost strategy was not effective in reducing the worm burden of animals, while vaccination with DNA-Sm14 induced partial reduction. Using both vaccines in the homologous prime-boost model, we found that the modification of the strategy did not alter IgG2a production, although reduced IFN- production by cells recovered from the broncho-alveolar space compared to DNA-Sm14 immunized mice. After infection, immunization with DNA-Sm14/DNA-Hsp65 didnt modify the animals parasitic burden, however systemically, reduced eosinophils number. When the profile of memory cells in vaccinated animals was evaluated, we verified increased numbers of CD8+ T cells and lower numbers of CD4+ T cells in the spleen of animals immunized with both vaccines simultaneously. In conclusion, the vaccines DNA-Sm14 and DNA-Hsp65 in both strategies, prime-boost heterologous or homologous, were not able to generate protection against experimental infection with S. mansoni, and we propose that, partly, the decrease of IFN-, IL-10 levels, increase of IgG1/IgG2a ratio and the stimulation of CD8+ T cells rather than CD4+, may have contributed to the low efficacy of the vaccination protocols tested.
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Laugsch, Magdalena, Jochen Seebach, Hans Schnittler, and Rolf Jessberger. "Imbalance of SMC1 and SMC3 Cohesins Causes Specific and Distinct Effects." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-127228.
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SMC1 and SMC3 form a high-affinity heterodimer, which provides an open backbone of the cohesin ring, to be closed by a kleisin protein. RNAi mediated knock-down of either one heterodimer partner, SMC1 or SMC3, is expected to cause very similar if not identical phenotypes. However, we observed highly distinct, protein-specific phenotypes. Upon knock-down of human SMC1, much of SMC3 remains stable, accumulates in the cytoplasm and does not associate with other cohesin proteins. Most of the excess nuclear SMC3 is highly mobile and not or only weakly chromosome-associated. In contrast, human SMC3 knock-down rendered SMC1 instable without cytoplasmic accumulation. As observed by differential protein extraction and in FRAP experiments the remaining SMC1 or SMC3 proteins in the respective SMC1 or SMC3 knock-down experiments constituted a cohesin pool, which is associated with chromatin with highest affinity, likely the least expendable. Expression of bovine EGFP-SMC1 or mouse EGFP-SMC3 in human cells under conditions of human SMC1 or SMC3 knock-down rescued the respective phenotypes, but in untreated cells over-expressed exogenous SMC proteins mis-localized. Paucity of either one of the SMC proteins causes RAD21 degradation. These results argue for great caution in interpreting SMC1 and SMC3 RNAi or over-expression experiments. Under challenged conditions these two proteins unexpectedly behave differently, which may have biological consequences for regulation of cohesin-associated functions and for human cohesin pathologies.
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Peeples, Craig. "Implementation of the SM12 Solvation Model into ADF and ADF-BAND." Journal Of Chemical Theory and Computation, 2016. http://hdl.handle.net/1993/31781.
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Modeling systems in liquid is imperative to chemistry, as many reactions take place in liquid, and nearly all of biochemistry is in the liquid state. Solvation Model 12 (SM12) is the newest Generalized Born Approximation iteration of a series of solvation models from Minnesota, it shows great promise for accurate, description of solutions. Shown is the full implementation of SM12 in to the pure Slater Type Orbital code, the Amsterdam Density Functional (ADF) package in particular. The model performs as well as its Gaussian Type Orbital counterpart. The model has been extended to account for periodic boundary conditions, as presented by the ADF-BAND code. The extension to infinite boundaries creates interesting edge effects that need to be taken into consideration, and are accounted for through cut off approximations and a screening function to ensure the potential is well-behaved.<br>October 2016
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Laugsch, Magdalena, Jochen Seebach, Hans Schnittler, and Rolf Jessberger. "Imbalance of SMC1 and SMC3 Cohesins Causes Specific and Distinct Effects." Public Library of Science, 2013. https://tud.qucosa.de/id/qucosa%3A27288.
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SMC1 and SMC3 form a high-affinity heterodimer, which provides an open backbone of the cohesin ring, to be closed by a kleisin protein. RNAi mediated knock-down of either one heterodimer partner, SMC1 or SMC3, is expected to cause very similar if not identical phenotypes. However, we observed highly distinct, protein-specific phenotypes. Upon knock-down of human SMC1, much of SMC3 remains stable, accumulates in the cytoplasm and does not associate with other cohesin proteins. Most of the excess nuclear SMC3 is highly mobile and not or only weakly chromosome-associated. In contrast, human SMC3 knock-down rendered SMC1 instable without cytoplasmic accumulation. As observed by differential protein extraction and in FRAP experiments the remaining SMC1 or SMC3 proteins in the respective SMC1 or SMC3 knock-down experiments constituted a cohesin pool, which is associated with chromatin with highest affinity, likely the least expendable. Expression of bovine EGFP-SMC1 or mouse EGFP-SMC3 in human cells under conditions of human SMC1 or SMC3 knock-down rescued the respective phenotypes, but in untreated cells over-expressed exogenous SMC proteins mis-localized. Paucity of either one of the SMC proteins causes RAD21 degradation. These results argue for great caution in interpreting SMC1 and SMC3 RNAi or over-expression experiments. Under challenged conditions these two proteins unexpectedly behave differently, which may have biological consequences for regulation of cohesin-associated functions and for human cohesin pathologies.
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Queiroz, Maria Nayane de. "Síntese e caracterização dos vidros cálcio boroteluretos dopados com Sm2O3." Universidade Federal do Maranhão, 2016. http://tedebc.ufma.br:8080/jspui/handle/tede/1347.
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Previous issue date: 2016-11-25<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão (FAPEMA)<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ)<br>The Sm2O3-doped calcium borotellurite glasses studied in this research were synthesized by melt-quenching method, characterized according to their structural, thermal, spectroscopic and optical properties and analyzed as a function of TeO2 concentration. The analysis of the properties was performed by the following characterizations: X-ray diffraction, volumetric density, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), optical absorption spectroscopy, differential thermal analysis (DTA), specific heat, refractive index, photoluminescence and lifetime decay. In addition, molar volume, optical band gap, electronic polarizability, number of ions per cubic centimeter, interionic distance, chromaticity, DE/DM ratio and orange/red ratio values were also evaluated. The results have showed that the increase of TeO2 concentration increased the volumetric density (~41%). The X-Ray spectra confirmed the amorphous nature of the samples. The Raman and FTIR results indicated the presence of the following structures: TeO3, TeO3+1, TeO4, BO3 and BO4. Moreover, the increase of nonbridging oxygen was confirmed. The increase of the TeO2 concentration decreased the specific heat and the glass transition temperature of the samples. The refractive index increased, due to an increase of density and electronic polarizability. The insertion of the doping agent was confirmed by the optical absorption spectra, which presented peaks characteristic of Sm3+ ions (most intense peak at ~402 nm). The emission intensity of the Sm3+ ions decreased (~2.2%) with the increase of TeO2 concentration. The chromaticity of the samples analyzed by CIE diagram showed small variation at x and y positions. However, under visual inspection, the variation of the emitted color was not observed. The emission intensity as a function of temperature, showed a decrease for all samples. The lifetime for the emission at ~598 nm also presented a reduction with the increase of TeO2 content, due to the increase of NBOs. Therefore, the synthesized materials present good properties, and finds their applications as potential candidate for optical devices, such as solid state lasers, Light-emitting diodes (LEDs), among others.<br>Os vidros cálcio boroteluretos dopados com Sm2O3 estudados neste trabalho foram sintetizados pelo método de fusão/resfriamento e caracterizados quanto às suas propriedades estruturais, térmicas, espectroscópicas e ópticas. Essas propriedades foram analisadas em função da concentração de TeO2. A análise das propriedades foi feita por meio das seguintes caracterizações: densidade volumétrica (método de Arquimedes), difração de raios-X, espectroscopia Raman, espectroscopia no infravermelho via transformada de Fourier (FTIR), espectroscopia de absorção óptica, análise térmica diferencial (DTA), calor específico, índice de refração, fotoluminescência e tempo de vida, além do cálculo dos valores de energia de band gap óptico, polarizabilidade eletrônica, número de íons por centímetro cúbico, distância interiônica, cromaticidade, razão dipolo elétrico/dipolo magnético (DE/DM) e razão laranja/vermelho. A densidade e o volume molar tiveram um aumento simultâneo devido ao aumento da massa molar do vidro. Os espectros de difratometria de raios-X mostraram que todas as amostras são amorfas e sem a presença de cristalitos. A temperatura de transição vítrea e o calor específico das amostras diminuíram com o aumento da concentração de TeO2. Os resultados de Raman e FTIR mostraram a presença das estruturas TeO3, TeO3+1, TeO4, BO3 e BO4.O índice de refração também teve um aumento, devido ao aumento da densidade e da polarizabilidade eletrônica. Por meio dos espectros de absorção óptica foi comprovada a inserção do dopante nas amostras, pois apresentam picos de absorção característicos do Sm3+, sendo o pico mais intenso em ~402 nm. A intensidade de emissão teve uma redução (~2,2%) com o aumento de TeO2. O tempo de vida para a emissão em ~598 nm também teve uma redução com o aumento da concentração de TeO2, devido ao aumento de oxigênios não-ligados (NBOs). A cromaticidade das amostras analisadas pelo diagrama CIE, mostrou uma pequena variação nas posições x e y, no entanto, sob inspeção visual não houve variação da cor emitida. Os resultados mostraram que o material sintetizado apresenta boas propriedades, com potencial para ser aplicado em dispositivos fotônicos, como lasers de estado sólido, lasers emissores de luz (LEDs), dentre outros.
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Bergman, Martinkauppi Louise, and Qiuping He. "Performance Evaluation and Comparison of Standard Cryptographic Algorithms and Chinese Cryptographic Algorithms." Thesis, Blekinge Tekniska Högskola, Institutionen för datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-18234.
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Background. China is regulating the import, export, sale, and use of encryption technology in China. If any foreign company wants to develop or release a product in China, they need to report their use of any encryption technology to the Office of State Commercial Cryptography Administration (OSCCA) to gain approval. SM2, SM3, and SM4 are cryptographic standards published by OSCCA and are authorized to be used in China. To comply with Chinese cryptography laws organizations and companies may have to replace standard cryptographic algorithms in their systems with Chinese cryptographic algorithms, such as SM2, SM3, and SM4. It is important to know beforehand how the replacement of algorithms will impact performance to determine future system costs. Objectives. Perform a theoretical study and performance comparison of the standard cryptographic algorithms and Chinese Cryptographic algorithms. The standard cryptographic algorithms studied are RSA, ECDSA, SHA-256, and AES-128, and the Chinese cryptographic algorithms studied are SM2, SM3, and SM4. Methods. A literature analysis was conducted to gain knowledge and collect information about the selected cryptographic algorithms in order to make a theoretical comparison of the algorithms. An experiment was conducted to get measurements of how the algorithms perform and to be able to rate them. Results. The literature analysis provides a comparison that identifies design similarities and differences between the algorithms. The controlled experiment provides measurements of the metrics of the algorithms mentioned in objectives. Conclusions. The conclusions are that the digital signature algorithms SM2 and ECDSA have similar design and also similar performance. SM2 and RSA have fundamentally different designs, and SM2 performs better than RSA when generating keys and signatures. When verifying signatures, RSA shows comparable performance in some cases and worse performance in other cases. Hash algorithms SM3 and SHA-256 have many design similarities, but SHA-256 performs slightly better than SM3. AES-128 and SM4 have many similarities but also a few differences. In the controlled experiment, AES-128 outperforms SM4 with a significant margin.<br>Bakgrund. Kina reglerar import, export, försäljning och användning av krypteringsteknologi i Kina. Om ett utländskt företag vill utveckla eller släppa en produkt i Kina måste de rapportera sin användning av krypteringsteknologi till Office of State Commercial Cryptography Administration (OSCCA) för godkännande. SM2, SM3 och SM4 är kryptografiska standarder som lagligt får används i Kina. Organisationer och företag kan behöva byta ut krypteringsalgoritmerna i sina system till kinesiska krypteringsalgoritmer för att uppfylla kraven för de kinesiska lagarna. Det är därför viktigt att i förväg veta hur ersättningen av algoritmer kommer att påverka prestandan för att utvärdera framtida kostnader för systemet. Syfte. Genomföra en teoretisk studie och prestanda jämförelse av standard krypteringsalgoritmer och kinesiska krypteringsalgoritmer. De standard krypteringsalgoritmerna är RSA, ECDSA, SHA-256 och AES-128. De kinesiska krypteringsalgoritmerna är SM2, SM3 och SM4. Metod. En litteraturanalys har genomförts för att få en bättre förståelse av de valda algoritmerna. Ett experiment har genomförts för att samla mätvärden av de bestämda parametrarna och för att sedan kunna ranka mätvärdena. Resultat. Litteraturanalysen gav en jämförelse som identifierar likheter och skillnader mellan algoritmerna. Det kontrollerade experimentet gav mätvärden av parametrarna för algoritmerna nämnda i syftet. Slutsatser. Slutsatserna är att de digitala signatur-algoritmerna SM2 och ECDSA har liknade design och också liknade prestanda. SM2 och RSA har fundamentala skillnader i deras design, och SM2 har bättre prestanda vid nyckelgenerering samt signaturgenerering. Vid verifiering av signaturer så visar RSA likvärdig prestanda i vissa fall och sämre prestanda i andra fall. Hashfunktionerna SM3 och SHA-256 har också många likheter i sin design, men SHA-256 presterar lite bättre än SM3. AES-128 och SM3 har många design likheter men också några skillnader. I det kontrollerade experimentet så presterar AES-128 bättre än SM4 med stor marginal.
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James, Rosalina Dee. "Cohesin proteins SMC1 and SMC3 : roles in aneuploidy and in meiotic chromosome dynamics /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/6333.
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MAKHLOGA, ASHISH, and VIDESH KUMAR. "Sm3+ IONS DOPED BOROSILICATE GLASS FOR VISIBLE PHOTONIC DEVICE APPLICATIONS." Thesis, DELHI TECHNOLOGICAL UNIVERSITY, 2021. http://dspace.dtu.ac.in:8080/jspui/handle/repository/18625.
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An intense reddish-orange colour radiating Samarium doped Aluminium Calcium
borosilicate (BSACS) glasses were synthesized with the help of the melt-quench method to
analyze the photoluminescence properties using characterization methods like XRD, FT-IR,
photoluminescence (PL) excitation, PL emission, and PL decay. XRD and FT-IR reveal the
non-crystalline behavior along with the presence of numerous functional groups in BSACS
host glass correspondingly. Under 402 nm excitation, three major peaks were found in the
emission spectra which perfectly resembles to 4G5/2 → 6H5/2 (562 nm), 4G5/2 → 6H7/2 (599
nm), and 4G5/2 → 6H9/2 (646 nm) transitions of Samarium ions. 4G5/2 → 6H9/2 transition at 599
nm is comparatively more intense and noticeable. PL decay observed for 4G5/2 state reveals
the exponential nature in which curves are fitted by using bi-exponential and tri- exponential
fitting to assess the practically measured lifetimes (τexp). It is observed that the τexp values are
decreasing with increasing Samarium ion concentration due to the cross-relaxation energy
transference. All of the findings indicate that Sm3+ doped borosilicate glass is suitable for its
usage in visible reddish orange photonic devices.
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Ramos, Henrique Roman. "Desenvolvimento e caracterização de uma vacina antiesquistossomose composta pela proteína Sm14 de Schistosoma mansoni utilizando a subunidade B da toxina colérica (CTB) com adjuvante." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-30072009-092218/.
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Introdução: o desenvolvimento de uma vacina contra a esquistossomose será um importante avanço no controle desta doença crônica e muitas vezes debilitante, afetando milhões de pessoas em todo o mundo. Neste trabalho, descrevemos o uso da subunidade B da toxina colérica (CTB) geneticamente fusionada com Sm14 - uma proteína ligadora de ácidos graxos de Schistosoma mansoni - como uma tentativa de desenvolver uma vacina antiesquistossomose. Métodos: proteínas recombinantes foram expressas em um sistema procariótico, purificadas por diferentes métodos cromatográficos e caracterizadas tanto por métodos imunoquímicos como por métodos espectroscópicos. Experimentos de imunização foram realizados em camundongos fêmeas, da linhagem BALB/c e a eficácia da vacina determinada através da análise da carga parasitária após o desafio com cercárias de S. mansoni e através da análise histopatológica das reações granulomatosas ao redor dos ovos aprisionados no tecido hepático dos camundongos. Resultados: a administração subcutânea de Sm14 reduziu em 27% a carga parasitária nos animais vacinados. Por outro lado, a vacinação intranasal apenas demonstrou uma redução estatisticamente significativa quando CTB esteve presente na formulação. Além disso, a co-administração de CTB e Sm14 reduziu em média 30% a área das lesões granulomatosas hepáticas. Conclusão: o uso de CTB demonstrou ser um importante adjuvante de mucosas; contudo, quando utilizada juntamente com a proteína Sm14, esta molécula não resultou em níveis satisfatórios de redução parasitária em um modelo murino para infecção esquistossomótica.<br>Introduction: developing a vaccine against schistosomiasis would be an important advance on the control of this chronic and debilitating disease which afflicts millions of people worldwide. Herein we describe the use of the non-toxic B subunit of cholera toxin (CTB) genetically fused to Sm14 - a fatty-acid binding protein from Schistosoma mansoni - as an attempt to the development of an antischistosomiasis vaccine. Methods: recombinant proteins were expressed on a prokaryotic system, purified by different chromatographic methods and both immunochemically and spectroscopically characterized. Immunization experiments were made on females BALB/c mice and vaccines efficacy was assessed by analyzing the worm-burden after challenge infection with S. mansoni cercariae and by analyzing its effect on the hepatic granulomatous reactions around trapped eggs. Results: subcutaneous administration of Sm14 reduced in 27% the worm burden on animals. On the other hand, intranasally vaccination only displayed a statistically significant reduction when CTB was added to the formulation. Furthermore, coadministrating CTB and Sm14 reduces in 30% the area of hepatic granulomas. Conclusion: the use of CTB may be an important tool for mucosal adjuvanticity; however it did not provide, together with Sm14, satisfactory levels of protection on a murine model for Schistosomiasis infection.
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Brännström, Kristoffer. "Molecular dissection of established and proposed members of the Op18/Stathmin family of tubulin binding proteins." Doctoral thesis, Umeå universitet, Molekylärbiologi (Medicinska fakulteten), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1949.
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My initial aim was a functional analysis of the conserved Op18/stathmin family of microtubule-regulators, which includes the ubiquitous cytosolic Op18 protein and the neural membrane-attached RB3 and SCG10 proteins. The solved X-ray structure has shown that these proteins form a complex with tubulin -heterodimers via two imperfect helical repeats, which result in two head-to-tail aligned heterodimers in a tandem-tubulin complex. We have analyzed GTP exchange and GTP hydrolysis at the two exchangeable GTP-binding sites (E-site) within the tandem-tubulin complex. A comparison of Op18, RB3 and SCG10 proteins indicates that Op18/Stathmin family proteins have evolved to maintain the two heterodimers in a configuration that restrains the otherwise potent GTPase productive interactions facilitated by the head-to-head alignment of heterodimers in protofilaments. We concluded from these studies that tubulin heterodimers in complex with Op18/stathmin family members are subject to allosteric effects that prevent futile cycles of GTP hydrolysis. To understand the significance of the large differences in tubulin affinity of Op18, RB3 and SCG10, we have fused each of the heterodimer-binding regions of these three proteins with the CD2 cell-surface protein to generate confined plasma membrane localization of the resulting CD2 chimeras. We showed that, in contrast to CD2-Op18, both the CD2-SCG10 and CD2-RB3 chimeras sequester tubulin at the plasma membrane, which results in >35% reduction of cytosolic tubulin heterodimer levels. However, all three CD2-chimeras, including the tubulin sequestration-incompetent CD2-Op18, destabilize interphase microtubules. Given that microtubules are in extensive contact with the plasma membrane during the interphase, these findings indicate that Op18-like proteins have the potential to destabilize microtubules by both sequestration and direct interaction with microtubules. Sm16/SmSLP (Stathmin-Like Protein) has been identified as a protein released during skin penetration of the Schistosoma mansoni parasite. This protein has been ascribed both anti-inflammatory activities and a functional similarity with the conserved cytosolic tubulin-binding protein stathmin/Op18. However, our studies refuted any functional similarity with stathmin/Op18 and we found instead that Sm16/SmSLP is a lipid bilayer binding protein that is taken up by cells through endocytosis. To study immuno-modulatory properties of Sm16/SmSLP, we designed an engineered version with decreased aggregation propensity, thus facilitating expression and purification of a soluble Sm16 /SmSLP protein from the eukaryotic organism Pichia pastoris. Determination of the hydrodynamic parameters revealed that both the recombinant and native Sm16/SmSLP is a ~9-subunits oligomer. The recombinant protein was found to have no effect on T lymphocyte activation, cell proliferation or the basal level of cytokine production of whole human blood or monocytic cells. Interestingly, however, recombinant Sm16 was found to potently inhibit the cytokine response to the Toll-like receptor (TLR) ligands lipopolysaccharide (LPS) and Poly(I:C). Since Sm16 specifically inhibits degradation of the IRAK1 signaling protein in LPS stimulated monocytes, it seems likely that inhibition is exerted proximal to the TLR-complex.
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Bersweiler, Mathias. "From Sm1-xGdxAl2 electronic properties to magnetic tunnel junctions based on Sm1-xGdxAl2 and/or [Co/Pt] electrodes : Towards the integration of Zero Magnetization ferromagnets in spintronic devices." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0146/document.
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Le contexte général de ce travail est le développement et l'intégration de nouveaux matériaux magnétiques ayant des propriétés originales et d'intérêt potentiel pour la spintronique. En tant que matériau ferromagnétique d’aimantation nulle, le composé Sm1-xGdxAl2 (SGA) suscite un intérêt particulier, puisqu’il est capable, dans son état magnétique compensé, de polariser en spin un courant d’électrons. Dans un premier temps, des expériences de photoémission résolues en angle et en spin sur synchrotron ont permis d’effectuer une analyse précise de la structure électronique selon diverses directions de la zone de Brillouin et d’estimer de manière directe la polarisation de spin au niveau de Fermi du composé SGA. Dans un second temps, une attention particulière a été portée aux multicouches [Co/Pt] et aux JTMs à base de [Co/Pt]. Les multicouches [Co/Pt] constituent la seconde électrode des JTMs à base de SGA. Leurs propriétés magnétiques (en particulier l'anisotropie perpendiculaire et l'aimantation à saturation) ont été soigneusement étudiées en fonction de l'épaisseur de Pt et de la nature de la couche tampon (Pt, MgO ou Al2O3), et en liaison avec leurs caractéristiques structurales. Leur intégration dans des JTMs à base de [Co/Pt] a permis ensuite de remonter d’une part à la polarisation tunnel effective des multicouches [Co/Pt] et d’autre part aux configurations magnétiques des différentes électrodes, configurations parfaitement expliquées et reproduites par des simulations micro-magnétiques. Dans un troisième temps, les résultats de magnéto-transport au sein des JTMs SGA/MgO/[Co/Pt] sont présentés et discutés<br>The general context of this work is the development and integration of new magnetic materials with original properties of potential interest for spintronic applications. In this field, the Sm1-xGdxAl2 (SGA) compound drives a particular attention, as a zero-magnetization ferromagnet that can exhibit a spin polarization in its magnetic compensated state. In a first step, synchrotron-based angle and spin resolved photoemission spectroscopy experiments have permitted to perform an accurate analysis of the electronic structure along various directions of the Brillouin Zone and to get a direct estimation of the spin polarization at the Fermi level. In a second step, a special attention has been the paid to [Co/Pt] multilayers and to [Co/Pt]-based MTJs. The [Co/Pt] multilayers would constitute the second electrode in SGA-based MTJs. Their magnetic properties (especially the perpendicular anisotropy and the saturation magnetization) have been carefully investigated as a function of Pt thickness and nature of the buffer layer (Pt, MgO or Al2O3), and in close connection with structural characteristics. Their integration in [Co/Pt]-based MTJs has permitted to determine the [Co/Pt] effective tunnel polarization and to unravel the magnetic configurations of both electrodes which are perfectly explained and reproduced by micromagnetic simulations. In a third step, the results concerning the magneto-transport experiments in SGA/MgO/[Co/Pt] MTJs are presented and discussed
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Hora, Vanusa Pousada da. "Construção e avaliação da rLTB/SM14 : uma quimera recombinante candidata a uma vacina contra esquistossomose e fasciolose." Universidade Federal de Pelotas, 2006. http://guaiaca.ufpel.edu.br/handle/123456789/1241.
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Previous issue date: 2006-10-30<br>Schistosomiasis, caused by Schistosoma mansoni, is the second most prevalent parasitic
disease worldwide causing chronic disease in millions of people in developing countries.
Similarly, fascioliasis, caused by the trematode Fasciola hepatica, represents a recognized
unsolved agricultural problem responsible for economic losses as well as causing a
significant number of human infections worldwide. Although chemotherapy for both
parasites has been available, this approach has limitations, including high reinfection
rates in endemic areas. Vaccines represent the most attractive long-term alternative to
invert this scenario. Accordingly, the World Health Organization selected S. mansoni fatty
acid-binding protein 14kDa (Sm14) as one out of two anti-schistosome vaccine priority
candidates for human clinical trials. Furthermore, Sm14 is the only vaccine candidate to
have been shown to afford significant immune protection against both of the above-mentioned
helminthes. The objective of this study was to develop and evaluate in mice a
recombinant subunit vaccine containing the Sm14 fused to the B subunit of the heat-labile
enterotoxin of Escherichia coli (LTB), which is a potent immunoadjuvant; furthermore,
was describe the production and characterization of monoclonal antibodies (MAbs)
against the Sm14 for use as a tool to detect and characterize Sm14 and for
development of future diagnostic test. The ltb and sm14 gene were obtained by PCR
amplification from E. coli DNA and plasmid pAESm14, respectively, and fused by PCR.
The recombinant chimera was expressed in E. coli and purified by nickel affinity
chromatography. Groups of outbreed Swiss mice were immunized with three footpad
doses of either rLTB/Sm14, rLTB/Sm14 plus aluminum hydroxide (Al(OH)3), rSm14 plus
Al(OH)3, rLTB or Al(OH)3. Levels of protection were determined by number of worms
recovered after S. mansoni cercarial challenge. The pooled sera of immunized mice were
evaluated by ELISA and Western blot. The results showed that the chimera protein was
able to elicit specific antibody production to rSm14 and rLTB, however the use of LTB as
adjuvant to rSm14 immunization failed to enhance protection against challenge.
Furthermore, seven MAbs were obtained after immunization of BALB/c mice with
rLTB/Sm14. MAbs isotyping revealed that five were of the isotype IgG1, one belonged to
the IgG2b isotype and another to the IgM isotype. These MAbs will be usefull for
monitoring protein expression in recombinant systems, protein stability and may have
potential for developing diagnostic test.<br>A esquistossomose, causada por Schistosoma mansoni, é a segunda doença parasitária
mais prevalente no mundo causando doença crônica em milhões de pessoas em países
em desenvolvimento. Semelhantemente, a fasciolose, causada pelo trematódeo Fasciola
hepatica, representa um reconhecido problema agrícola responsável por perdas
econômicas assim como causa um significante número de infecções em humanos por
todo mundo. Embora a quimioterapia para ambos os parasitas esteja disponível, ela
tem apresentado limitações, incluindo altas taxas de reinfecção em áreas endêmicas.
Vacinas representam a alternativa mais atraente para inverter este cenário. Assim, a
Organização Mundial da Saúde selecionou a proteína ligadora de ácidos graxos 14kDa
de S. mansoni (Sm14) como uma de duas candidatas à vacina anti-esquistossomose
prioritárias para triagem clínica em humanos. Além disso, a Sm14 é a única proteína
candidata a vacina que induz imunidade protetora significativa contra ambos os
helmintos acima mencionados. O objetivo deste estudo foi desenvolver e avaliar em
camundongos uma vacina de subunidade contendo a Sm14 fusionada com a
subunidade B da enterotoxina termolábil de Escherichia coli (LTB), a qual é um potente
imunoadjuvante; além disso, foi descrever a produção e caracterização de anticorpos
monoclonais (MAbs) contra a Sm14 para usa-los como uma ferramenta para detectar e
caracterizar a Sm14 e para o desenvolvimento de futuro teste diagnóstico. Os genes ltb
e sm14 foram amplificados por PCR a partir do DNA de E. coli e do plasmídeo
pAESm14, respectivamente, e fusionados por PCR. A quimera recombinante foi
expressa em E. coli e purificada por cromatografia de afinidade em coluna com níquel.
Grupos de camundongos suíços não singênicos foram imunizados por via subcutânea
com três doses de rLTB/Sm14, rLTB/Sm14 mais hidróxido de alumínio (Al(OH)3), rSm14
plus Al(OH)3, rLTB ou Al(OH)3. Os níveis de proteção foram determinados através do
número de parasitas recuperados após desafio com cercárias de S. mansoni. O pool de
soros dos camundongos imunizados foi avaliado por ELISA e Western blot. Os
resultados mostraram que a proteína quimera foi capaz de estimular a produção de
anticorpos específicos para Sm14 e LTB, contudo o uso de LTB como adjuvante para
imunização de rSm14 falhou em aumentar a proteção contra o desafio. Além disso, sete
MAbs foram obtidos após imunização de um camundongo BALB/c com rLTB/Sm14. A
isotipagem dos MAbs revelou que cinco foram do isotipo IgG1, um pertencente ao
isotipo IgG2b e outro ao isotipo IgM. Estes MAbs serão úteis para monitorar a
expressão da proteína em sistemas recombinantes, a estabilidade protéica e pode ter
potencial para desenvolver teste diagnóstico.
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Khazzan, Salwa. "Systèmes nanocristallins Sm1-s(Fe,Mo)5+2s : étude des propriétés structurales et magnétiques." Phd thesis, Université Paris-Est, 2010. http://tel.archives-ouvertes.fr/tel-00600687.
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Ce travail se situe dans le cadre général de l'étude des nanostructures obtenues par mécanosynthèse qui font l'objet d'intenses recherches dans le domaine des aimants permanents de nouvelle génération et de l'enregistrement magnétique. L'objectif de l'étude du système Sm-Fe-Mo est de suivre l'effet de la substitut ion partielle du fer par le molybdène ainsi que l'effet de l'insertion d'un élément léger tel que le carbone sur leurs propriétés magnétiques afin d'établir une corrélation entre leur microstructure et leurs propriétés magnétiques. Nous avons montré que la mise en solution du molybdène est bien possible. La phase 2/17 ainsi obtenue possède une température de Curie (Tc) égale à 434K. Avec le taux de substitution croissant, on découvre un changement de phase vers une phase monoclinique 3/29 du type Nd3(Fe,Ti)29 de Tc égale à 459K, puis vers une structure quadratique (1/12 de Tc=551K). Ces phases d'équilibre, obtenues à haute température de recuit, dérivent toutes de la structure CaCu5. Elles correspondent à la substitution ordonnée des atomes de Sm par des haltères de Fe. A plus basse température de recuit, on découvre l'apparition de nouvelles phases, ne figurant pas dans les diagrammes d'équilibre. Nous avons déterminé les stchiométries respectives de ces phases par analyse des diagrammes de diffraction des RX par la technique de Rietveld. Ces phases hexagonales possèdent des propriétés magnétiques plus intéressantes que les phases d'équilibre. L'insertion du carbone change drastiquement les propriétés magnétiques des différentes phases
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Avisou, Aymeric Dufour Catherine. "Croissance épitaxiale et propriétés magnétiques de films de Sm1-xGdxAl2 un ferromagnétique sans moment /." [S.l.] : [s.n.], 2006. http://www.scd.uhp-nancy.fr/docnum/SCD_T_2006_0141_AVISOU.pdf.
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Cardoso, Luciana Santos. "Avaliação da resposta imune in vitro induzida por antígeno de Schistosoma mansoni em indivíduos asmáticos." Instituto de Ciências da Saúde, 2005. http://repositorio.ufba.br/ri/handle/ri/22556.
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Dissertação_ISC_Luciana Santos Cardoso.pdf: 4791824 bytes, checksum: adeea3b3d364d4f4df9afdcb3f7f0a53 (MD5)<br>Estudos vêm demonstrando diminuição da reatividade aos testes cutâneos para
alérgenos e menor gravidade da asma em indivíduos infectados por helmintos,
principalmente Schistosoma mansoni. A inibição da resposta inflamatória na asma
em indivíduos infectados pelo S. mansoni parece ser mediada pela IL-10, desde
que tem sido observada maior produção desta citocina por células de asmáticos
infectados pelo S. mansoni estimuladas com o antígeno 1 do Dermatophagoides
pteronyssinus (Der p1) quando comparado a asmáticos não infectados. A IL-10 é
capaz de inibir a produção de citocinas do tipo Th2 e a degranulação de
mastócitos e liberação de mediadores inflamatórios, fatores envolvidos na
patogênese das doenças alérgicas. O principal objetivo deste estudo foi avaliar a
capacidade dos antígenos de S. mansoni Sm22.6, Sm14, PIII, P24 e Sm29 de
estimular a produção de IL-10 in vitro, por células mononucleares de sangue
periférico de asmáticos infectados e não infectados pelo S. mansoni. Foram
também avaliadas as produções de IL-5, IL-13 e IFN-g. Foi adicionado Sulfato de
Polimixina B às culturas estimuladas com os antígenos recombinantes para
bloquear a ação da endotoxina em induzir a síntese de citocinas, desde que as
proteínas recombinantes foram clonadas em Escherichia coli. As concentrações
das citocinas foram medidas nos sobrenadantes das culturas de células
utilizando-se a técnica ELISA sanduiche. Foi demonstrado que todos os antígenos
de S. mansoni avaliados neste estudo induziram a produção de IL-10 por células
de indivíduos infectados e de asmáticos não infectados. Nas culturas de 24 horas
de células de asmáticos não infectados, os antígenos P24 e Sm 29 induziram as
mais altas concentrações de IL-10 (828 ± 415 pg/mL e 891 ± 213 pg/mL,respectivamente). Em todos os grupos avaliados e para todos os antígenos
usados, foi baixa a produção de IFN-g (valores em torno de 100 pg/mL) e os
níveis de IL-5 foram abaixo do limite de detecção (15,6 pg/mL). A produção de IL-
13 induzida pelos antígenos Sm22.6, P24 e PIII foi avaliada no grupo de
asmáticos não infectados, e foram observadas concentrações de 68 ± 60 pg/mL,
55 ± 49 pg/mL e 81 ± 67 pg/mL, para os respectivos antígenos. A adição dos
antígenos de S. mansoni Sm22.6, P24 e PIII às culturas de asmáticos não
infectados estimuladas com o Der p1 resultou em aumento na produção de IL-10.
O fato dos antígenos de S. mansoni avaliados neste estudo terem induzido a
produção de IL-10 e baixas concentrações de IL-5, IL-13 e IFN-g por células de
asmáticos não infectados sugere que os mesmos pode ser futuramente utilizados
como vacina para prevenir doenças alérgicas.
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Santos, Tatiane dos. "Teste toxicológico pré-clínico para o desenvolvimento da vacina anti-helmíntica baseada no antígeno r-Sm14 de Schistosoma mansoni." reponame:Repositório Institucional da FIOCRUZ, 2012. https://www.arca.fiocruz.br/handle/icict/7898.
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Previous issue date: 2014<br>Fundação Oswaldo Cruz. Instituto Oswaldo Cruz<br>Para avaliação dos parâmetros de segurança do preparado vacinal r-Sm14 contra a esquistossomose, testes pré-clínicos e clínicos devem ser realizados. O presente estudo tem por objetivo avaliar a segurança do antígeno recombinante Sm14 e do adjuvante LIPID-A (GLA) quando administrado em coelhos subcutaneamente utilizando múltiplas doses. O teste toxicológico do antígeno vacinal r-Sm14 foi realizado de acordo com o protocolo toxicológico adotado e desenvolvido por BAS Evansville e Corixa Corporation (2002), segundo as normas do FDA Good Laboratory Practice Regulations (21CFR Part 58) e CPMP guidance documents (CPMP/SWP/465/95 E CPMP/ICH302/95). Neste estudo, 24 coelhos (Oryctolagus cuniculus) da raça Nova Zelândia, sendo 12 machos e 12 fêmeas foram distribuídos em 4 grupos. Cada grupo foi composto por três coelhos machos e três fêmeas imunizados com antígeno r-Sm14 expresso em Pichia pastoris (Grupo A/Sm14Pp+GLA), antígeno r-Sm14 expresso em Escherichia coli (Grupo B/Sm14Ec + GLA), adjuvante GLA-SE (Grupo C) e PBS (Grupo D/controle). Foram avaliados diariamente o aspecto físico dos animais, o nível de estresse, consumo de alimentos e água; semanalmente, variação da evolução ponderal; e, antes e após as inoculações, por meio de sangrias, parâmetros bioquímicos e hematológicos. Ao final do teste todos os animais foram eutanasiados para investigação anatomopatológica. Os animais não apresentaram mudanças significativas no aspecto físico e no nível de estresse. Não houve diferença de peso estatisticamente significativa entre os grupos e todos os resultados encontrados estão de acordo com os dados fisiológicos esperados para coelhos. Os pesos de todos os órgãos e estruturas e a maioria dos parâmetros bioquímicos e hematológicos analisados se encontravam dentro da normalidade. A análise anatomopatológica evidenciou ausência de alterações macroscópicas e histopatológicas significativas na pele do local das imunizações e em todos os órgãos analisados. Alguns animais, inclusive do grupo controle, apresentaram pequenos focos de calcificação nos rins, comuns em coelhos, associados às condições nutricionais. Portanto, nenhum dado indicativo de qualquer ação tóxica provocada pela imunização com diferentes formulações da proteína r-Sm14 e/ou adjuvante foi encontrado, demonstrando uma completa segurança do preparado vacinal, dentro das condições experimentais apresentadas.<br>To assess the safety parameters for preparing a vaccine against schistosomiasis from recombinant r-Sm14, pre-clinical and clinical tests must be carried out. The aim of this study was to evaluate the safety of the r-Sm14 antigen and the adjuvant LIPID-A (GLA) when administered subcutaneously to rabbits in multiple doses. The toxicological test of the vaccine antigen r-Sm14 was performed according to the protocol developed and adopted by BAS Evansville and Corixa Corporation (2002), according to the standards of the FDA Good Laboratory Practice Regulations (21CFR Part 58) and the CPMP guidance documents (CPMP/SWP/465/95 and CPMP/ICH302/95). A total of 24 rabbits (Oryctolagus cuniculus) of the New Zealand breed were used (12 males and 12 females), distributed in four groups. Each group was composed of three males and three females, immunized with the r-Sm14 antigen expressed in Pichia pastoris (Group A/Sm14Pp+GLA), the r-Sm14 antigen expressed in Escherichia coli (Group B/Sm14Ec + GLA), the adjuvant GLA-SE (Group C) and PBS (Group D/control). The animals’ physical appearance, stress level and food and water consumption were assessed daily, while the weight evolution was measured weekly. Finally, the biochemical and hematological parameters were analyzed by means of blood tests before and after the inoculations. At the end of the test, all the animals were euthanized for anatompathological examination. The animals did not show significant changes in physical appearance and stress level. There also was no significant weight difference among the groups and all the data were in accordance with the physiological data expected for rabbits. The weights of all the organs and structures and the majority of the biochemical and hematological parameters analyzed were within the normal range. The anatomopathological examination revealed the absence of macroscopic and histopathological changes in the skin at the vaccination site and in all the organs analyzed. Some animals, including in the control group, presented small calcification foci in the kidneys, common in rabbits, associated with the nutritional conditions. Therefore, no signs of any toxic action caused by the immunization with the different formulations of the protein r-Sm14 and/or adjuvant were found, demonstrating the complete safety of the vaccine preparation, under the described experimental conditions.
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Garcia, Teresa Cristina Melo. "Avaliação da imunogenicidade de epitopos de células T das proteínas Sm14 e paramiosina do schistosoma mansoni em modelo murino." Universidade Federal de Minas Gerais, 2008. http://hdl.handle.net/1843/CMFC-7LLN2M.
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Sm14 and paramyosin are S. mansoni antigens able to induce partial protection in the murine model, and are recognized by individuals resistant to S. mansoni. Recently our group has identified Sm14 and paramyosin epitopes preferentially recognized by PBMC of S. mansoni resistant individuals [Sm14 (32-48), Sm14 (53-69), Para (6-22), Para (210-226), Para (355-371)]. In order to investigate the protective potential of these synthetic epitopes peptide-based vaccines formulations were prepared using a mixture of Sm14 and paramyosin peptides or Sm14 or paramyosin separately. Immunization of mice with peptide total mixture or Sm14 peptides were able to induce a Th1 type of immune response, that was associated respectively with a significant reduction on worm burden [(29%; 28%) and (26%; 36.7%)]; reduction in the number of viable eggs/female worms (46% and 67%); reduction in the number of granuloma (52% an 61%) and granuloma area (43% and 54%). On the other hand, paramyosin peptide immunization did not engender protective immunity or pathology reduction and it was associated with a Th2 type of immune response. Since eggs in host tissues are the major cause of pathology, and schistosomes do not replicate within their mammalian hosts, an anti-fecundity vaccine, could decrease human pathology and disease transmission. Here we observed that immunization with Sm14 T cell epitopes previous recognized by resistant individuals seems to be able to induce reduction in fecundity and pathology, and therefore are potential candidates to compose a subunit vaccine against schistosomiasis.<br>A Sm14 e paramiosina são antígenos vacinais do S. mansoni capazes de induzir proteção em modelo murino e são reconhecidos por indivíduos resistentes à infecção pelo S. mansoni. Recentemente nosso grupo identificou epitopos da Sm14 e paramiosina preferencialmente reconhecidos por PBMCs de indivíduos resistentes a infecção e reinfecção por S. mansoni [Sm14 (32-48), Sm14 (53-69), Para (6-22), Para (210-226), Para (355-371)]. A fim de investigar o potencial protetor destes epitopos sintéticos, formulações vacinas baseadas em peptídeos foram preparadas usando uma mistura de peptídeos da Sm14 e paramiosina ou Sm14 ou paramiosina separadamente. Imunização de camundongos com mistura total de peptídeos ou peptídeos da Sm14 foi capaz de induzir uma resposta imune do tipo Th1 que foi associada respectivamente a uma redução na carga de vermes de {(29%, 28%) e (26%, 36.7%)}; redução do número de ovos viáveis/fêmea de 46% e 67%; redução no número de granulomas de 52% e 61% e na área dos granulomas de 43% e 54%. Por outro lado, imunização com peptídeos da paramiosina não induziu imunidade protetora ou redução da patologia e foi associada a uma resposta imune do tipo Th2. Uma vez que os ovos nos tecidos são a principal causa da patologia e os vermes adultos não se replicam dentro do hospedeiro mamífero, uma vacina anti-fecundidade poderia reduzir a patologia humana e transmissão da doença. Aqui nós observamos que imunização com epitopos de células T da Sm14 previamente reconhecidos por indivíduos resistentes parece ser capaz de induzir redução na fecundidade e redução da patologia e, portanto são candidatos em potencial a compor uma vacina de subunidades contra esquistossomose.
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Ara?jo, Roberto C?mara de. "Estudo das propriedades magn?ticas e estruturais do composto (Sm1 - xMMx)2Fe17 e seus nitretos." Universidade Federal do Rio Grande do Norte, 1994. http://repositorio.ufrn.br:8080/jspui/handle/123456789/16632.
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Previous issue date: 1994-08-20<br>Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico<br>A substitui??o parcial do Sm por um Mischmetal( M M ) rico em Cc, no composto Sm2FC17 e seus nitretos foi estudada atrav?s da metalografia ?tica, An?lisa Termomagn?tica, Espectroscopia Mossbauer, Difratometria de raio-x e Medidas de Magnetiza??o.
Um sistema de fase ?nica ? encontrado para uma substitui??o at? 50% at. de Mischmetal. Esses intermet?licos na forma Fe17(Sm1- xMMx)2 absorvem um substancial quantidade de nitrog?nio.
Ap?s a nitrogena??o h? um aumento no volume da c?lula unit?ria. Uma mudan?a espetacular ? observada nas propriedades magn?ticas dos nitretos em rela??o ao composto de origem, Fe17(Sm1 xMMx)2. A temperatura de Curie sofre uma varia??o da ordem de 350? C. como mais importante, a Anisotropia basal do composto de origem muda para uma dire??o uniaxial. Um campo de Anisotropia (HA) de 7.2 T e Magnetiza??o de Satura??o MS de 100 emu/g, foi registrada para o nitreto com o maior percentual de mischmetal
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Luu, Magnus, and Johan Karlsson. "Server Message Block : En undersökning av potentiella prestandavinster mellan SMB 2.1 och SMB 3.0 i ett befintligt nätverk." Thesis, Linnéuniversitetet, Institutionen för datavetenskap (DV), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-34008.
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Examensarbetet behandlar en jämförelse av Server Message Block 3.0 och föregångaren 2.1 i ett befintligt nätverk. Jämförelsen utfördes i fyra laborationsmiljöer bestående av fyra operativsystem: Windows Server 2008 R2, Windows Server 2012, Windows 7 ochWindows 8. Sammanlagt har fyra tester utförts: Förstudie, Test 1, Test 2 och Test 3. Förstudien utfördes för att testa nätverksprestanda mellan två datorer. De andra testerna satte SMB 2.1 och SMB 3.0 på prov. I Test 1 ansågs SMB 3.0 prestera sämre än SMB 2.1, för att bekräfta resultaten kontaktades Jose Barreto på Microsoft. Barreto påstod att programvarorna Windows Defender och Windows Firewall kunde ge upphov till störningar och prestandaminskningar. Test 2 och Test 3 utfördes därför med tidigare nämnda programvaror avaktiverade. Resultaten var som tidigare varierande men kan mycket väl bero på andra faktorer som exempelvis dåligt uppdaterade nätverkskortsdrivrutiner.<br>The dissertation addresses the comparison of Server Message Block 3.0 and its predecessor SMB 2.1 on an existing network. The comparison was performed in four laboratory environments consisting of four operating systems: Windows Server 2008R2, Windows Server 2012, Windows 7 and Windows 8. A total of four tests were performed: Feasibility Study, Test 1, Test 2 and Test 3. The feasibility study was conducted to test the network performance between two computers while the other tests put SMB 2.1 and 3.0 to the test. In Test 1 SMB 3.0 was considered to underperform in difference to SMB 2.1, to confirm the results Jose Barreto at Microsoft were contacted. Barreto stated that the two software applications Windows Defender and Windows Firewall could cause interference and performance reductions. Test 2 and Test 3 was therefore performed with the previously mentioned software disabled. The results were as previously varied but may well be due to other factors such as poorly updated network card drivers.
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Silva, Tarcio de Castro. "Síntese e Espectroscopia Óptica das fases estáveis do sistema Y2O3-Al2O3 dopadas com Nd3+ e Sm3+." Universidade Federal de Goiás, 2013. http://repositorio.bc.ufg.br/tede/handle/tede/3844.
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Previous issue date: 2013-11-28<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>The development of rare earths luminescent materials has been
subject of many research works searching for technological applications in
the manufacture of solid-state lasers, photonic and biomedical devices,
manufacturing of displays, and others. The system Y2O3-Al2O3 has three
stable crystalline phases: Y3Al5O12 (YAG), YAlO3 (YAP) and Y4Al2O9 (YAM).
Among them, YAP and YAG are widely studied and used in the manufacture
of solid-state lasers. In this work, we used the modified polymeric precursor
method to synthesize YAG, YAP, and YAM doped with 0.5 and 1% of Nd3+
and Sm3+ ions replacing Y3+. Analysis of X ray diffraction and vibrational
spectroscopy confirmed the achievement of crystalline single phases.
Transmission electron images show grain sizes ranging from 80 to 300 nm.
We verified a strong influence of the different matrices symmetries on the
optical emission of these rare earths photoluminescent ions.<br>O desenvolvimento de materiais luminescentes dopados com terras
raras tem sido alvo de muitas pesquisas para aplicações em diversas áreas
como na fabricação de lasers de estado sólido, em fotônica, fabricação de
displays, aplicações médicas e outros. Matrizes no sistema Y2O3-Al2O3 têm
se mostrado interessantes para hospedar centros luminescentes. Este
sistema possui três fases cristalinas estáveis: Y3Al5O12 (YAG), YAlO3 (YAP)
e Y4Al2O9 (YAM); dentre elas, o YAP e YAG são amplamente estudadas e
utilizadas para fabricação de lasers do estado sólido. Neste trabalho,
utilizando o método de precursores poliméricos, sintetizamos essas três
fases dopadas com os terras raras Nd3+ e Sm3+ em concentrações de 0,5 e
1% de substituição de átomos de Y3+. Análises de difrações de raios X e
absorção no infravermelho confirmaram a obtenção das fases cristalinas.
Imagens de microscopia eletrônica de transmissão mostram tamanho de
grãos entre 80 e 300nm. Através das análises de fotoluminescência,
verificamos forte dependência dos espectros de emissão com as simetrias
dos sítios cristalinos das três matrizes.
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Bessat, Mohamed Said Nooh. "Functional characterisation of cohesin subunit SMC3 and separase and their roles in the segregation of large and minichromosomes in Trypanosoma brucei." Thesis, University of Hull, 2009. http://hydra.hull.ac.uk/resources/hull:2179.
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The genome of the African trypanosome, Trypanosoma brucei, presents an unusual karyotype in which two main classes of chromosomes, large and small minichromosomes, need to be faithfully replicated and segregated during the cell cycle. Although the large and minichromosomes are colocalised and segregated by association with the mitotic spindle, minichromosomes exhibit segregation patterns that differ from those observed for large chromosomes. To address whether this difference is reflected at a molecular level, two different proteins that have highly conserved functions in eukaryotic chromosomes segregation were characterised in this study. The first protein, SMC3, is a component of the chromosome cohesion apparatus that holds sister chromatids together after their replication until segregation at anaphase. The second protein, separase, is a cysteine protease that resolves sister chromatid cohesion at the onset of anaphase and has, in other organisms, additional functions during mitosis. The T. brucei cohesin subunit, TbSMC3, localised to the nucleus as a chromatin-bound protein from G1 phase until metaphase and dissociated from chromatin during anaphase until the completion of cell division. On the other hand, cytoplasmic localisation of separase with nuclear exclusion was prevalent until the onset of metaphase when the protein re-localised to the nucleus, thus providing a potential control mechanism to prevent premature cohesin cleavage. Interference with the normal expression of SMC3 and separase by RNA interference resulted in defects in growth rate, cell cycle progression and chromosomes segregation. TbSMC3 depletion produced a lethal phenotype and inhibition of cell cycle progression. Similarly, lethality with severe inhibition of cell cycle progression was the main feature of separase depletion. Using fluorescence in situ hybridisation (FISH), it was shown that SMC3 depletion had no visible effect on the symmetric segregation of the minichromosome population, but interferes with the faithful mitotic segregation of large chromosomes. In contrast, separase depletion blocks the segregation of both large and minichromosomes. In separase-depleted mitotic cells, cohesins remained bound to chromatin, which is in contrast to rapid dissociation of cohesins from chromatin in wild-type mitotic cells. The severity of segregation phenotypes after separase depletion was additionally explained by defects in the mitotic spindle assembly. In both SMC3 and separase depleted cells, cytokinesis in the absence of mitosis/karyokinesis was not inhibited in procyclic cells, resulting in the generation of anucleate 'zoid' cells. The lethality imposed on trypanosome cells after depletion of both SMC3 and separase proteins indicate that they can serve as potential drug targets for anti-parasite chemotherapy.
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Parenti, I. "CORNELIA DE LANGE SYNDROME AND RELATED DISORDERS: NEW INSIGHTS INTO GLOBAL TRANSCRIPTIONAL DISTURBANCES DUE TO MUTATIONS IN CHROMATIN-ASSOCIATED FACTORS." Doctoral thesis, Università degli Studi di Milano, 2016. http://hdl.handle.net/2434/352028.
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Cornelia de Lange syndrome (CdLS) is a rare disorder characterized by an extensive clinical heterogeneity. The main features of the syndrome are characteristic facial dysmorphisms and a variable level of intellectual disability, growth retardation and developmental delay. Though, the number and severity of the clinical signs vary among patients. An extensive genetic heterogeneity partially accounts for the reported clinical variability. Mutations in different cohesin-associated proteins are in fact responsible for the onset of the syndrome. The known CdLS-genes include NIPBL, SMC1A, SMC3, RAD21 and HDAC8. Alterations in the cohesin loader NIPBL are found in more than half of CdLS cases and are associated with a classical phenotype and with a high frequency of limb malformations. In addition, mosaicism has been proven to play an important role in association with NIPBL. Mutations in the structural elements SMC1A, SMC3 and RAD21 and in the regulator HDAC8 account for about 10-15% of CdLS cases. The phenotype of those patients who harbor mutations in these genes is usually milder or atypical. The five genes all together, also taking into account the role of mosaicism, can explain about 70% of CdLS cases.
In an internationally assembled cohort of patients we were able to identify 109 mutations in NIPBL, 8 mutations in SMC1A, 15 mutations in SMC3 and 11 mutations in HDAC8, thus increasing the total number of mutations so far described for CdLS. In addition, by the use of next generation sequencing techniques we were able to identify mutations in five genes different from cohesin in six unrelated patients with a clinical diagnosis of CdLS. The five genes include those encoding for different subunits of the chromatin remodeling complex named SWI/SNF and for the transcriptional repressor ANKRD11. Mutations in these genes have been so far associated to Coffin-Siris syndrome and KBG syndrome, respectively. Protein-protein interaction experiments also showed a direct interaction of the SWI/SNF subunit SMARCB1 with the cohesin-related proteins NIPBL and SMC3. These direct link between cohesin and SWI/SNF subunits indicate that mutations affecting the two protein complexes might determine the deregulation of overlapping sets of genes.
Our newly identified variants contribute to a better understanding of the correlation between genotype and phenotype in the presence of mutations in the known-CdLS genes. Notwithstanding, different pehotypes have been observed in patients carrying the same DNA alteration, hence suggesting that environmental factors may play an important role in the delineation of the observed clinical features. Additionally, the identification of mutations in chromatin-associated factors responsible for syndromes different from CdLS indicate the existence of a broad pleiotropy that should be taken into account while assessing the clinical and molecular diagnosis.
Furthermore, we investigated the molecular mechanisms underlying the syndrome in the presence of missense substitutions or small in-frame deletions in SMC1A, a X-linked gene that localizes in a region of the X-chromosome that partially escapes X-inactivation in humans. Our expression analysis revealed that the transcript is expressed at higher levels in females as compared to males, and that there are no differences in the expression of the SMC1A protein between healthy and affected females. In addition, pyrosequencing analysis showed that CdLS female patients harboring mutations in SMC1A tend to express the wild type allele at higher levels as compared to the mutant allele. All together, these data suggests that the pathogenesis of the syndrome in the presence of mutations affecting SMC1A which do not disrupt the reading frame might be linked to a dominant negative effect exerted by the mutant protein on the wild type.
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Pezo, Altamirano Rosa Mercedes. "Diseño del ramal de alimentación de 1460 sm3/h de gas natural para la compañía minera Luren." Universidad Nacional de Ingeniería. Programa Cybertesis PERÚ, 2010. http://cybertesis.uni.edu.pe/uni/2010/pezo_ar/html/index-frames.html.
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Sudoh, K., Y. Ichino, Y. Yoshida, et al. "Magnetic field dependence of critical current density in Sm/sub 1+x/Ba/sub 2-x/Cu/sub 3/O/sub 6+/spl delta// films prepared by pulsed laser deposition." IEEE, 2003. http://hdl.handle.net/2237/6742.
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Ramos, Celso Raul Romero. "A proteína ligadora dos ácidos graxos Sm14 de Schistosoma mansoni: estrutura gênica, polimorfismo, expressão heteróloga em E. coli e significado estrutural e funcional das suas formas polimórficas e mutantes." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-08072009-155141/.
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A esquistossomose é a mais importante das doenças helmínticas humanas em termos de morbidez e mortalidade. A proteína Sm14 de Schistosoma mansoni, que pertence à família de proteínas ligadoras de ácidos graxos (fatty acid-binding proteins, FABPs) (Moser et al., 1991), mostrou um bom nível de proteção (65%) contra a esquistossomose em animais experimentais (Tendler et al., 1996). No presente trabalho foram desenvolvidos sistemas de expressão que possibilitará a produção da proteína Sm14 em larga escala em E.coli. Com o intuito de conhecer a estrutura do gene da proteína Sm14, foi clonado um fragmento de DNA genômico de S. mansoni que contém a seqüência codificante da proteína Sm14. Como os outros membros da família gênica das FABP, o gene para a proteína Sm14 contém quatro \"exons\" separados por três \"introns\" de 674, 585 e 42 bp. Esta é a primeira descrição da estrutura gênica de um membro das FABP correspondente a um helminto. A Sm14 é uma proteína que pode ser potencialmente usada como vacina. Estudamos a existência de polimorfismo em duas linhagens de S. mansoni endêmicas do Brasil: LE e BH. Para a análise de polimorfismo, a ORF correspondente à proteína Sm14 foi amplificada por RT-PCR do RNA total de vermes adultos de S. mansoni. Os produtos de amplificação independentes foram clonados no vetor pGEM-T e seqüenciados. As análises de seqüências mostraram duas isoformas principais para a proteína Sm14: Sm14-M20, com seqüência idêntica a proteína Sm14 previamente reportada para a linhagem de Puerto Rico de S. mansoni (Moser et AL., 1991), e Sm14-T20, onde o códon da Met20 (ATG) mudou para o códon de Thr (ACG) (polimorfismo M20T). Dois clones mostraram uma deleção de seqüência de aminoácidos correspondente ao \"exon\" 3 inteiro (clones ΔExon3), gerada por \"splicing\" alternativo. As outras trocas observadas acontecem em posições onde os aminoácidos são menos conservados e estão representados apenas por um único clone que podem ter sido obtidas por mutagênese na PCR. A metionina correspondente à posição 20 na Sm14 é altamente conservada nas FABP dos mais diversos organismos,e não se tem nenhuma outra proteína com treonina nesta posição. Para o estudo da estrutura e função destas isoformas, os cDNAs correspondentes foram subclonados no vetor pAE (desenvolvido no nosso laboratório), assim como o mutante M20A (Sm14-A20) construído para efeitos de comparação. A estabilidade e estrutura das proteínas recombinantes purificadas foram caracterizadas por dicroísmo circular (CD). A comparação da estrutura e termoestabilidade mostrou que as formas Sm14-T20 e Sm14-A20 são menos termoestáveis do que a Sm14-M20 (um ΔTm de aproximadamente 10°C). Porém, todas as formas de Sm14 foram capazes de ligar o DAUDA [ácido 11-(dansylamino) undecanoico] com a mesma afinidade. Para poder diferenciar as propriedades de ligação de ácidos graxos pelas isoformas, experiências de competição do deslocamento do DAUDA por ácidos graxos naturais, foram realizadas. A partir destes dados podemos assumir que a forma Sm14-M20 liga melhor todos os ácidos graxos naturais testados do que a forma Sm14-T20. Porém esta forma mantém a capacidade de ligar ácidos graxos, ao contrario do mutante Sm14-A20. Pode-se deduzir como resultado destas experiências que a proteína Sm14-M20 é mais estável e liga com maior afinidade os ácidos graxos naturais do que a forma Sm14-T20. Pelo visto, a proteína Sm14-T20 tem menos estrutura-β, porém, mantém a capacidade de ligar moléculas hidrofóbicas. Ainda é desconhecido o papel funcional do polimorfismo da proteína Sm14 no metabolismo dos vermes de S. mansoni. Problemas de estabilidade da proteína Sm14 recombinante, durante seu transporte e armazenamento, comprometem sua viabilidade como vacina. Com o intuito de melhorar a estabilidade desta proteína, foi feita uma mutagênese no único resíduo de cisteína presente na Sm14 na posição 62. Este resíduo é responsável pela formação de dímeros, o que é relacionado a estabilização da perda de estrutura-β e precipitação da proteína. Esta cisteína foi trocada por serina (C62S) e por valina (C62V) por mutagênese sítio dirigida, resultando nas proteínas Sm14-M20S62 e Sm14-M20V62. As formas mutantes não apresentaram maior termoestabilidade, mas a renaturação após o aquecimento a 80°C atingiu quase 100%, diferentemente das proteínas com Cys62. As proteínas com o resíduo de cisteina trocado foram as únicas formas que conservaram a estrutura de β-barril após 3 meses de armazenamento a 4°C, como mostram as análises de dicroísmo circular, sendo a forma mais estável a proteína Sm14-M20V62. Após estes estudos, a isoforma Sm14-M20 com a mutação C62V (Sm14-M20V62) mostrou-se como a melhor alternativa ao antígeno Sm14-T20 usado até agora como modelo de vacina experimental para S. mansoni. Esta indicação deve ser confirmada em ensaios de imunização e posterior desafio com cercárias de S. mansoni.<br>The schistosomiasis is the most important human helmintic disease in terms of morbidity and mortality. The Sm14 protein of Schistosoma mansoni belongs to the family of fatty acid-binding proteins (FABPs) (Moser et aI. , 1991) and showed a good protection level as vaccine antigen against the schistosomiasis in experimental animals (Tendler et al., 1996). In the present work were developed systems for the expression of Sm14 protein that will facilitate its large scale production in E.coli.. In order to know the gene structure of the Sm14 protein, we amplified by PCR a genomic DNA fragment of S. mansoni that contains the coding sequence for the Sm14 protein. As the other members of the FABP family, the Sm14 gene contains four exons separated by three introns of 674,585 and 42 bp, respectively. This is the first detailed description of the genomic structure for a member of FABPs corresponding to a helmint. We also studied the existence of polymorphisms within two Brazilian endemic strains of S.mansoni: LE and BH. For the polymorphism analysis, the ORF corresponding to the Sm14 protein was amplified by RT-PCR from total RNA of S. mansoni adult worms. The independent amplified products were cloned into pGEM-T vector and sequenced. The sequence analyses showed two main isoforms: Sm14-M20, with identical sequence to that previously reported Sm14 protein from the Puerto Rican strain of S. mansoni (Moser et al., 1991), and Sm14-T20, where the codon for Met20 (ATG) was changed for the Thr codon (ACG) (M20T polymorphism). Two clones showed the same amino acid sequence deletion corresponding to the whole third exon (ΔExon3 clones), generated by alternative splicing. The other observed changes occurred in positions where the amino acids were less conserved and were just represented by only one clone that could be obtained by PCR mutagenesis. The methionine corresponding to the position 20 in Sm14 is highly conserved among FABPs and no other related protein has threonin in this position. To study the structure and function of these amino acid in the isoforms, the corresponding cDNAs were subcloned in to the pAE vector (developed in our laboratory), as well as the mutant M20A (Sm14-A20). The stability and structure of the purified recombinant proteins were characterized by circular dicroism (CD). The comparison of their structure and thermo stability showed that the forms Sm14-T20 and Sm14-A20 are less thermostable than Sm14-M20 (ΔTm around 10ºC). However, all of the Sm14 forms were capable to bind the DAUDA [11- (dansylamine) undecanoic acid] with similar affinities. To differentiate the fatty acid binding properties of Sm14 isoforms, displacement experiments of DAUDA with natural fatty acid were performed. From these data we can assume that the Sm14-M20 form binds better than the Sm14-T20 and Sm14-A20 forms of all natural fatty acid assayed. This suggests that the Sm14-20 protein is most stable and binds better the natural fatty acids than the Sm14-T20 form. Although the Sm14-T20 protein has less structure, it maintains the capacity to bind fatty acids. It is still unknown the functional role of this Sm14 protein polymorphism in the metabolism of S. mansoni worms. Stability problems of the recombinant Sm14 protein during its transport and storage, could hamper its use as vaccine. With the aim to improve the stability of this protein, it was made a mutagenese at the unique cysteine residue present in Sm14 at the position 62. This residue is responsible for the dimer formation and is related the loss of the terciary structure and precipitation of the protein. This cysteine was changed by serine (C62S) and for valine (C62V) by site directed mutagenesis, resulting in the proteins Sm14-M20S62 and Sm14-M20V62. The mutant forms did not present a higher thermal stability but the renaturation after heating at 80°C almost reached 100%, in contrast to Sm14 proteins with Cys62. These mutants conserved the β-barrel structure after 3 months of storage at 4°C, in contrast to proteins with Cys62, as shown by circular dicroism analyses. After these studies, the Sm14-M20 isoform with the C62V mutation (Sm14-M20V62) was considered the best alternative to the antigen Sm14-T20 used up to now as the model for an experimental vaccine for S. mansoni. This indication should be confirmed by immunization and posterior challenge with S. mansoni cercaria.
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Fan, Cuibai. "L'influence de la lactoferrine, de probiotiques et du SM3 (extrait enrichi en sphingolipides) sur des fonctions immunitaires de la souris." Phd thesis, AgroParisTech, 2008. http://pastel.archives-ouvertes.fr/pastel-00005539.
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Certains aliments ou composants des aliments ont des effets physiologiques et psychologiques bénéfiques en plus de leur rôle de base de couverture des besoins nutritionnels. Leur identification dans les produits alimentaires est un axe d'étude et de développement important des industriels de l'agroalimentaire. L'objectif de ce travail était de caractériser les effets induits par la consommation de lactoferrine, de deux souches de bactéries probiotiques (Lactobacillus acidophilus NCFM et Bifidobacterium animalis Bb12) et du SM3 (extrait enrichi en sphingolipides) sur le système immunitaire digestif et périphérique de souris BALB/c. Les ingrédients ont été inclus dans des régimes, seuls ou en association. Nos résultats montrent que les deux souches de bactéries se retrouvent viables en nombre suffisant dans les fèces pour effectuer les fonctions bénéfiques revendiquées. Le SM3 joue un rôle « positif » sur la flore lactobacille. Les différents régimes ont modulé des paramètres immunitaires innés (phagocytose) et adaptatifs (immunoglobulines et la répartition des cellules T et DCs). Notamment, les résultats sur le recrutement des DCs de type Th1 sont originaux par rapport aux travaux déjà publiés. Ces modifications ont été observées aux niveaux local et systémique. Le ratio NON-HDLch/HDLch a été amélioré par les régimes contenant des bactéries et/ou du SM3. Nous avons mis en évidence un effet dose pour le SM3 et un phénomène d'interaction entre le SM3 et les probiotiques. Nos résultats apportent des arguments pour classer ces trois ingrédients parmi les ingrédients fonctionnels mais des travaux supplémentaires sont nécessaires pour comprendre les mécanismes sous-jacents.
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Matos, Israel Roger Montoya. "Efeito de altas pressões nas propriedades estruturais e espectroscópicas de vidros silicatos alcalinos dopados com íons terras raras (Nd3+, Sm3+, Pr3+)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/169536.
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O objetivo deste trabalho foi sintetizar matrizes vítreas homogêneas à base de óxido de silício e óxidos alcalinos (lítio, sódio e potássio) dopados com íons terras raras (Nd3+, Sm3+, Pr3+) que serviram como sondas locais, para investigar o efeito da densificação induzida por altas pressões (7,7 GPa) destas matrizes nas propriedades estruturais e espectroscópicas. Para a caracterização estrutural foram realizadas medidas de espectroscopia de absorção no infravermelho e Raman dos vidros produzidos revelando o efeito de cada íon alcalino na matriz de sílica. Para avaliar o efeito da densificação em alta pressão nos vidros, as medidas espectroscópicas foram realizadas antes e após o processamento em 7,7 GPa. Foi possível observar alterações no perfil da banda vibracional da sílica em torno de ~1050 cm-1 e ~1100 cm-1 nos espectros infravermelhos e Raman relacionadas a cada íon alcalino e à densificação. Estas alterações tornaram-se mais pronunciadas à medida que o tamanho do íon modificador aumentava. As propriedades espectroscópicas foram avaliadas através de medidas de absorção óptica e luminescência sob excitação em 488 nm. Os espectros de absorção dos três sistemas estudados foram avaliados antes e após terem sido submetidas à pressão 7,7 GPa, apresentando picos de absorção referentes às transições eletrônicas entre níveis 4f-4f características dos íons neodímio, samário e praseodímio. Observou-se mudanças na intensidade das bandas de absorção e desdobramentos de algumas transições pelo efeito da adição do íon alcalino na matriz e da densificação, sendo mais evidente para o silicato contendo potássio e dopado com neodímio. Para as amostras dopadas com samário os espectros de absorção mostraram uma forte intensidade para a transição 6H15/2, não observada em outros sistemas vítreos, o que poderia estar associado à presença dos íons alcalinos na matriz. Entretanto, a intensidade desta transição diminuiu pelo efeito da pressão. As amostras dopadas com praseodímio apresentaram todas as transições características na região do visível e o desdobramento da banda 3P1 foi mais evidente para o vidro silicato contendo potássio após ter sido submetido a 7,7 GPa. Na região do infravermelho foi observado o desdobramento da banda hipersensível 3F2 para o silicato de potássio antes e após a densificação em alta pressão. Com os espectros de absorção dos três sistemas estudados foram calculados os parâmetros de intensidade de Judd-Ofelt, Ωk (k=2,4,6) antes e após de terem submetidos ao tratamento de altas pressões, com os quais se calculou a probabilidade de transição radiativa de cada íon de terra rara utilizado como sonda e se verificou o caráter covalente das ligações presentes na matriz. Os respectivos espectros de luminescência também foram avaliados antes e após a densificação em alta pressão. Os vidros silicatos dopados com neodímio mostraram desdobramento na transição 4F3/2→4I9/2, o qual se manteve após a densificação. Os vidros silicatos com íons alcalinos e dopados com samário apresentaram uma forte luminescência no laranja/vermelho, cuja intensidade diminuiu após a densificação. Para os vidros dopados com praseodímio foi observada uma intensa emissão na região do vermelho. Foi possível identificar alterações irreversíveis induzidas pela pressão nos valores de densidade, índice de refração e nos parâmetros radiativos dos íons terras raras. Os resultados obtidos indicam que as propriedades espectroscópicas dos íons terras raras podem ser utilizadas como sondas locais para investigar alterações induzidas pela densificação de materiais vítreos em altas pressões. A alta pressão induz alterações irreversíveis nas distâncias e ângulos de ligação entre os íons terras raras e os íons ligantes que alteram o campo cristalino e, portanto, as propriedades espectroscópicas medidas.<br>The main goal of this work was to synthesize homogeneous vitreous matrices of silicon oxide and alkaline oxides (lithium, sodium and potassium) doped with rare earth ions (Nd3+, Sm3+, Pr3+) that served as local probes to investigate the effect of the densification induced by high pressure into their structural and spectroscopic properties. Raman and infrared spectroscopy were used for structural characterization of the glasses revealing the effect of each alkaline ion. To evaluate the effect of the densification induced by high pressure, the vibrational spectroscopy measurements were performed before and after processing the glasses at 7.7GPa during 15 min. It was possible to observe variations in the shape of the bands around ~1050 cm-1 and ~1100 cm-1 related to silica in the infrared and Raman spectra. These variations depended on the alkaline ion and densification and they were more pronounced as the size of the alkaline ion increased. The spectroscopic properties were evaluated by optical absorption and photoluminescence under excitation at 488 nm. The absorption spectra of the three systems studied were evaluated before and after processing at 7.7 GPa and the absorption peaks were related to electronic transitions between 4f-4f levels of neodymium, samarium and praseodymium ions. Changes were observed in the intensity of the absorption bands and on the splitting of some transitions. These changes depended on the alkali ion and on densification, being more evident for the silicate glass containing potassium and doped with neodymium. For samples doped with samarium the absorption spectra showed a strong intensity for the transition 6H15/2 not observed in other systems which might be associated with the presence of the alkali ions in the matrix. However, the strength of the transition decreased after densification under pressure. The samples doped with praseodymium showed all the characteristics transitions in the visible region and the unfolding 3P1 band was more evident for glass containing potassium silicate after densification. In the infrared region it was observed the splitting of the hypersensitive band 3F2 for potassium silicate before and after the high pressure densification. With the absorption spectra of the three systems studied, the intensity parameters of Judd-Ofelt, Ωk (k = 2,4,6) were calculated before and after having submitted to high pressure treatment, with which the probability of radiative transition of each rare earth ion used as a probe and the covalent character of the bonds present in the matrix was verified. The correspondent photoluminescence spectra were also evaluated before and after the high pressure densification. It was observed the splitting of the transition 4F3/2 → 4I9/2, for the glasses doped with Nd, which remained after densification Alkaline silicates glasses doped with Sm ions showed a strong luminescence in the orange/red, whose intensity decreased after densification. For glasses doped with Pr it was observed an intense emission in the red region. It was possible to identify irreversible changes induced by pressure on values of density, index of refraction and radiative parameters of the rare earths ions. The results indicated that the spectroscopic properties of the rare earth ions can be used as local probes to investigate changes induced by densification of glassy materials at high pressures. The high pressure induces irreversible changes in distances and bond angles between the rare earth ions and ligands that modify the crystal field and, therefore, the spectroscopic properties.
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Machado, Marco Antonio Cunha. "Estudo por espalhamento Raman de efeitos anarmônicos e transição de fase do PbTiO3 : Sm3+ induzidos por pressão hidrostática e variação de temperatura." Universidade Federal de São Carlos, 2007. https://repositorio.ufscar.br/handle/ufscar/4898.
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Previous issue date: 2007-10-05<br>Financiadora de Estudos e Projetos<br>In this work it was investigated, by using Raman spectroscopy, the effect of
the substitucional disorder on the vibrational properties of the ferroelectric
ceramics PbTiO3 doped with Samarium, at different temperatures and hydrostatic
pressures. This material is interesting from the technological point of view because
it is a combination between a material with intense ferroelectric properties and a
rare earth ion, with very well known optical properties. From the academic point of
view, the main purpose was to study qualitatively and quantitatively the combined
chemical and structural effects on the phonon spectrum, which was achieved
through measurements of the frequency shifts and broadenings of the vibrational
modes, that is, the anharmonic effects. It was also investigated the changes in the
Curie temperature, the critical transition pressure values and frequency pressure
and temperature coefficients generated by substitucional disorder. A special
attention was done to the behavior of the lower frequency mode, the so called soft
mode, which plays an important role, whose frequency tends to zero with the
approach of the ferroelectric-paraelectric transition. The Raman scattering, due to
its sensitivity to short range order, to the character nondestructive, noninvasive is
a technique well adapted to the purpose of the present study. The importance of
the material and the choice of the technique are justified by the great number and
quality of publications related to both in the international literature.<br>Neste trabalho foram investigados, com o auxílio da Espectroscopia
Raman, os efeitos de desordem substitucional nas propriedades vibracionais da
cerâmica ferroelétrica PbTiO3, dopado com Samário, com variações de
temperatura e pressão. Esse material é interessante do ponto de vista de
aplicações tecnológicas, pois é uma combinação entre um material com
propriedades ferroelétricas intensas e um íon terra rara com propriedades ópticas
muito bem conhecidas. O objetivo deste trabalho foi estudar qualitativa e
quantitativamente os efeitos combinados de desordem química e estrutural sobre
o espectro de fônons, o que foi feito através de medidas da variação das
freqüências dos modos vibracionais em função de pressão hidrostática e
temperatura, ou seja, os efeitos anarmônicos. Investigou-se também as possíveis
variações no valor da temperatura de Curie (Tc), pressão crítica de transição (Pc).
O comportamento do modo de mais baixa freqüência, chamado soft mode,
desempenha um papel importante, pois, através de seu comportamento, cuja
freqüência tendendo a zero com aproximação da transição ferroelétricaparaelétrica,
pode-se avaliar as propriedades ferroelétricas. O espalhamento
Raman, devido o seu caráter não destrutivo, não invasivo e pela sua sensibilidade
a uma grande variedade dessas características, é uma técnica perfeitamente
adaptada a esse propósito. A importância do material e a escolha da técnica são
justificadas pelo grande número e qualidade de publicações relacionadas a
ambos. Some-se o fato da grande variedade de materiais aos quais a técnica tem
sido usada para estudo assim como a inovação nas áreas de aplicação.
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Frand, Geneviève. "Synthèse et caractérisation de couches minces obtenues à partir d'oxydes d'antimoineSynthèse et caractérisation des propriétés métal/isolant de la solution solide Sm1-xNdxNiO3." Le Mans, 1995. http://www.theses.fr/1995LEMA1008.
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Ce travail de these est consacre a la recherche de nouveaux materiaux possedant des proprietes optiques modulables lorsqu'ils sont mis sous forme de couches minces. Le memoire comporte deux grandes parties, l'une est consacree a la realisation, la caracterisation et l'evaluation des proprietes electro-optiques de couches minces d'oxydes d'antimoine, et l'autre a l'etude de la transition metal-isolant intervenant dans des materiaux appartenant a une solution solide d'oxyde de nickel et de terres rares. Dans la premiere partie, le chapitre i concerne la preparation et la determination structurale de materiaux massifs de composition msbo#3 (m = li, na, k, ag). Les parametres structuraux sont precises grace aux affinements des diagrammes de diffraction des rayons x sur poudre pour chaque phase etudiee. L'elaboration de couches minces par evaporation sous vide de ces oxydes et la caracterisation de ces couches fait l'objet d'un deuxieme chapitre. De nombreuses techniques de caracterisation ont ete mises en uvre, chacune apportant des renseignements complementaires sur la composition des depots d'oxydes d'antimoine. Il apparait alors que les couches minces obtenues a partir de msbo#3 sont constituees de deux phases, l'une etant sb#2o#3 et l'autre etant une phase amorphe riche en materiau m (li, na, ag). Des couches minces de sb#2o#3 ont alors ete preparees. Le troisieme chapitre presente une etude du comportement electro-optique des differentes couches minces et de la nature de la reaction electrochimique mise en jeu. Tous les depots presentent un phenomene electrochimique s'accompagnant d'une variation de leur pouvoir de reflexion et de transmission. Bien que toutes les couches minces soient constituees d'oxydes d'antimoine iii, il existe une difference de comportement optique vis-a-vis de la reflexion suivant qu'elles contiennent ou non un alcalin. Ce comportement optique est lie a l'insertion electrochimique du lithium au sein du materiau en couche mince. La seconde partie de ce travail de these concerne la preparation et la caracterisation structurale et electrique de la solution solide sm#1#-#xnd#xnio#3. Tous les materiaux de la solution solide presentent une structure perovskite orthorhombique. La propriete remarquable de ces composes est une transition de phase metal-isolant, elle est etudiee par des mesures d'analyse thermique (dsc) et de conductibilite electrique (mesure a l'aide d'hyperfrequences). Ces mesures ont permis de determiner d'une part la temperature a laquelle intervient le phenomene de transition metal-isolant et d'autre part l'enthalpie de transformation et la conductivite metallique des differentes compositions de la solution solide. En accord avec la litterature, la transition metal-isolant de la solution solide s'interprete naturellement dans le cadre d'un modele mettant en jeu les orbitales de valence et de conduction de l'oxygene et du nickel. Le regime metallique trouve son origine dans la suppression du gap de transfert de charge entre les orbitales pleines et vides de l'oxygene et du nickel
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Brooks, Lisa. "Replacing the "Raise Your Hand to Speak" Rule with New Social and Sociomathematical Norms in an Elementary Mathematics Classroom." Doctoral diss., University of Central Florida, 2014. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/6249.
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This qualitative study documents the establishment of new social and sociomathematical norms in a second grade classroom. The teacher allowed students to speak directly to one another without having to raise their hands first during whole group mathematics instruction. Reform efforts in mathematics and the standards for mathematical practice contained in the Common Core State Standards call for students to discuss their reasoning with each other.
Data were collected through interviews with the teacher and students, field notes, and video-recorded lessons over the course of 23 days. An online survey tool was utilized to share selected video of the teacher's instruction. Initial professional development topics were chosen from research in mathematics education related to the social construction of understanding. Ongoing professional development was responsive to what occurred during instruction.
The literature suggests that teachers often utilize traditional teaching methods and struggle to deviate from established patterns regardless of their desire to implement change. The teacher in this study learned that allowing students to talk openly provided him with insight into their mathematical conceptions and misconceptions. The students initially viewed mathematics as a set of rules to follow and exhibited the role of passive recipients of information. This changed as students were provided opportunities to participate in discussions and in doing so developed a new understanding of their role during mathematics lessons. Mathematical errors became a catalyst for communication and were viewed by students as opportunities for assisting their peers.<br>Ed.D.<br>Doctorate<br>Education and Human Performance<br>Education
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Herrera, Carrillo Alvaro. "Propriedades espectroscópicas e estruturais de vidros de óxido de metais pesados dopados com íons Sm3+ e Pr3+ : efeito de altas pressões e da incorporação de nanopartículas de ouro." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/150259.
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Neste trabalho foram sintetizados vidros à base de óxidos de metais pesados dopados com os íons terras raras Sm3+ e Pr3+ e foi realizado um estudo das propriedades espectroscópicas e estruturais sobre a influência da incorporação de nanopartículas de ouro e de altas pressões. As diferentes famílias vítreas foram sintetizadas a partir de precursores óxidos em pó devidamente pesados tendo em conta o balanço estequiométrico. As nanopartículas metálicas de ouro foram produzidas via implantação iônica e via incorporação de Au2O3 na mistura dos óxidos de partida dos vidros sintetizados, seguida de tratamentos térmicos apropriados. As propriedades estruturais e espectrais foram investigadas através de análise térmica diferencial (ATD), difração de raios X (DRX), espectroscopia Raman, espectroscopia de absorção UV-VIS-NIR, fotoluminescência, microscopia eletrônica de varredura (MEV) e microscopia eletrônica de transmissão (MET). Os resultados obtidos demonstram que os sistemas vítreos sintetizados possuem excelentes propriedades térmicas e canais eficientes de emissão nas regiões do visível e infravermelho próximo. A presença das nanopartículas de ouro induz mudanças nos espectros de emissão dos íons terras raras devido às oscilações coletivas dos elétrons livres do metal interatuando com o campo eletromagnético ao redor dos íons Sm3+ e Pr3. Altas pressões causam uma densificação na matriz hospedeira. A consequente diminuição da distância interatômica entre íons seria responsável pelo decréscimo observado na intensidade dos espectros de emissão provavelmente devido à diminuição na população dos níveis 4G5/2 para o íon Sm3+ e 3P0-1D2 para o íon Pr3+ através de mecanismos não radiativos.<br>In this work heavy metal oxide glasses doped with Sm3+ and Pr3+ were synthesized. The spectroscopic and structural properties were investigated under the influence of gold nanoparticles and high pressure. The glass families were synthesized from the powder of the oxide precursors weighed properly considering the stoichiometric balance. The metallic gold nanoparticles were produced via ion implantation and through the incorporation of Au2O3 in the mixture of starting oxides in glasses synthesized, followed by appropriate heat treatments. The structural and spectral properties were investigated by differential thermal analysis (DTA), X diffraction rays (XRD), Raman spectroscopy, UV-VIS-NIR absorption, photoluminescence, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results demonstrated that the synthesized vitreous systems have excellent thermal properties and efficient emission channel in the visible and near infrared regions. The presence of gold nanoparticles induced changes in the rare earth emission spectra due to the collective oscillations of free electrons of the metal interacting with the electromagnetic field around the Sm3+ and Pr3+ ions. High pressure causes a densification in the host matrix. The consequent decrease in the interatomic distance between ions would be responsible for the decrease of the emission intensities observed probably due to a depopulation of 4G5/2 level to Sm3+ ion and 3P0-1D2 for the Pr3+ ion.
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BOATENG, KINGSLEY A. "STUDIES ON ARABIDOPSIS PROTEINS REQUIRED FOR THE ESTABLISHMENT AND RELEASE OF SISTER CHROMATID COHESION." Miami University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=miami1185209243.
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Del, Giudice Carmine. "SM13 regola l'interazione MDM2 – P53: effetti sul cancro e sul danno vascolare." Tesi di dottorato, 2015. http://www.fedoa.unina.it/10388/1/Del%20Giudice%20Carmine.pdf.
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Background: p53 è un noto soppressore tumorale che agisce regolando l'apoptosi in risposta al danno cellulare, regolando diversi meccanismi all'interno della cellula, come l'arresto del ciclo cellulare e l'apoptosi mitocondriale indipendentemente dalla sua attività trascrizionale. Recentemente sono stati sintetizzati due nuovi composti (ISA27 e SM13), che bloccano l'interazione MDM2-p53 e sono in grado di indurre apoptosi in cellule tumorali p53 wild-type (wt). Inoltre è noto che p53 è attivo nelle lesioni iperplastiche vascolari, nelle quali induce l'apoptosi delle cellule muscolari lisce (VSMC). Lo scopo di questo studio è stato quello di verificare l'efficacia di questi composti in tumori generati da una forma mutata del gene p53 senza attività trascrizionale (p53mt), e se p53 possa essere un target terapeutico per il trattamento di malattie vascolari, alla base delle quali vi è una iperproliferazione delle cellule vascolari
lisce.
Metodi: in vitro è stata valutata l'efficacia dei peptidi in linee cellulari tumorali con il gene p53wt, p53 mutato (p53mt) e p53 knock out (p53ko), e nella linea cellulare
VSMC. Lo studio in vivo è stato eseguito in topi nudi Balb/c.
Risultati: Sia ISA27 che SM13 riducono la proliferazione cellulare ed inducono apoptosi in vitro in cellule p53wt e p53mt, suggerendo che il meccanismo d'azione è p53 dipendente, non avendo alcun effetto nella linea tumorale p53ko, ma è indipendente dall'attività trascrizionale di p53. In vivo, ISA27 e SM13 inducono morte cellulare in
maniera dose dipendente attraverso l'attivazione della via apoptotica mitocondriale. In partiolare SM13 è più efficace di ISA27 nel ridurre la crescita del tumore. Nelle VSMC, il trattamento con SM13 è risultato efficace nel ridurre l'interazione p53/MDM2 ed aumentare i livelli di p53. Inoltre, in queste cellule SM13 inibisce la proliferazione cellulare e la sintesi del DNA ed è in grado in vitro, di indurre apoptosi p53 – dipendente.
Conclusione: Il nostro studio propone SM13 come composto anti-tumorale da utilizzare per il trattamento di tumori p53 dipendenti, anche in assenza di attività trascrizionale p53, e dimostra l'efficacia di SM13 nel ridurre la proliferazione delle VSMC, attraverso l'attivazione di un pathway apoptotico p53-dipendente, suggerendo il suo impiego in malattie vascolari iperproliferative, quali aterosclerosi e restenosi.
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Hu, Chien-Chiang, and 胡建強. "Research on Drosophila melanogaster smt3 P Element Disrupted Mutant." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/65298974037634798138.
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碩士<br>國立中山大學<br>生物醫學科學研究所<br>89<br>Yeast SMT3 (Suppressor of Mif2 temperature sensitive mutant 3) is a Mif-related prortein, and is first found in suppression Mif2 (Mitotic fidelity of chromosome transmission protein 2) mutant. So far, among animals of higher level, we have found the existence of 3 SMT3 isozymes (A,B,C). It’s known that SMT3A is located on chromosome 21. And smt3 sequence of Drosophila is similar to those of yeast or human in a percentage of 55%, 73%, and 52%.
We analyze 10 strains of flies with p element inserted into position 27C6-8 on chromosome 21 and found a p element mutant, P997, near the position of smt3 gene. Then we built fly’s smt3 mutation stock by using P element technology, and by using PCR, we can sieve out mutant fly fast and massively. Thus we can observe the expression of smt3 during the development of fly.
The P element of stock 11378 is inserted 300bp before smt3 start codon. After stock 11378’s crossing with W1118, we get smt3-null mutation. Then we found that smt3-null mutation is a recessive lethal mutant, fly will die in the forth period of embryo development. At that time, the cell nucleus has divided for about 10 to 13 times, also means 90 to 120 minutes after the embryo is produced. We also found two important characteristics about dead embryo of smt3-null mutation: (1) The DNA in the embryo is scattered and couldn’t be condensed in the nucleus. (2) Huge and abnormally-dispersed vacuoles are observed in the embryo.
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Chang, Hsiao-Chuan, and 張曉娟. "Isolation and characterization of Stenotrophomonas maltophilia phages SMA5 and SMT13." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/15553928879939073934.
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碩士<br>國立中興大學<br>分子生物學研究所<br>92<br>Eight strains of lytic phages, including SMA1 ~ SMA8, were isolated from 87 strains of S. maltophilia that were isolated from wastewater and catheter-related devices. SMA2, SMA5, and SMA6 could lyse most clinical isolates of S. maltophilia. These phages contain a double-strained DNA genome with a similar restriction pattern. Electron microscopy shows that SMA5 belonges to the family of Myoviridae. Pulsed-field gel electrophoresis shows that SMA5 has a genome of about 250 kb. N-terminal sequencing of four virion proteins reveals that SMA5 is a novel phage. Various S. maltophilia isolates were used for infection with SMA5, and varied degrees of growth inhibition were observed. No significant loss of phage infectivity was observed after storage of crude lysates of SMA5 at 4℃ for 16 months, indicating that SMA5 is stable. In the other way, it was found that 46 out of 87 collected S. maltophilia strains were able to release infective phage particles. DNA sequencing reveals that the genome of SMT13 is circular, with 33,525 nt in size. Forty-three open reading frames (ORFs) were identified on the SMT13 genome. Based on comparative the analysis of sequence conservation, genome organization, and morphology it is believed that SMT13 is similar to P2 and P2-like phages. Electron microscopy of SMT13 confirmed that this phage belonges to Myoviridae. In order to illustrate the phylogenetic relatedness, SMT13, prophage XccP1, prophage XacP1, P2 and P2-like phages were analyzed with programs BLAST, ClustalX, TreeView, TMHMM, Dot plot, SignalP, and GCG. The part of SMT13 genome containing genes coding for structural proteins, assembly proteins, and terminase is highly related to the P2 and P2-like phages. The other part of the SMT13 genome containing genes coding for lysis related proteins, DNA replication related proteins, lysogeny regulators is far related to the P2 and P2-like phages. The phylogenetic relatedness between SMT13 and prophages on the gamma Proteobacteria genome, including Xylella, Xanthomonas, Stenotrophomonas, and Pseudomonas, was further analyzed.
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Dhal, S. "Synthesis and Characterization of Sm3+ Doped CeO2 Nanoparticles." Thesis, 2010. http://ethesis.nitrkl.ac.in/1593/1/ethesis.pdf.
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Samaria-doped ceria powders were prepared with varying doping concentrations (0.05, 0.5, 1.0, and 2.0). The nanopowders were synthesized using inorganic salts of cerium ammonium nitrate and samarium nitrate. Cerium ammonium nitrate was used as the precursor for ceria and samarium nitrate as the precursor for Sm3+. Dodecylamine was used as surfactant. The characteristics of the sample were investigated by X-ray diffraction studies, DSC-TG analysis, UV, IR, SEM images and BET surface area measurement. From the thermal studies the mass loss was found to be 16 %. XRD data showed the as-prepared sample has cubic fluorite structure and the broad peaks implied that the crystallite size is small (~ 8 nm). 2 mol% Sm3+ doped CeO2 sample heated at 500C possesses high BET surface area of 75 m2/g. FT-IR results showed that the nanopowders heated at 500oC was free from surfactant
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Yang, Ming-Chang, and 楊明昌. "Identification 、Characterization and Sequence Analysis of smt3 Related Genes fo Caenorhabditis elegans." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/28751825823213314324.
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碩士<br>國立中山大學<br>生物學系<br>87<br>Caenorhabditis elegans is a 1-mm long, cylinder shape, soil-living nematode. It has been used as a model organism for biological research since 1963. Its life cycle take about 3 ~ 4 days, and consists of six stages include eggs, embryo, first-stage larvae (L1), second-stage larvae (L2), third-stage larvae (L3), fourth-stage larvae (L4), adults and dauer larvae. The size of genomic DNA of C. elegans is approximately 97 Mega base pair nucelotides within its six chromosomes. We used C. elegans as an experimental organism and try to identify hsmt3 family gene homologues. Using RT-PCR strategy, we obtained a hsmt3b homologue of C. elegans and termed cesmt3b. There were 3 different residues between hsmt3b and cesmt3b through alignment of the amino acid sequence. The different amino acids are threonine , glutamic acid 69, and leucine 84 instead of Ala12, Asp69, and Leu84, respectively. The smt3b protein was identical in human, bovine, porcine, mouse and rat. The residued difference between hsmt3b and cesmt3b revealed that this gene highly conserved. The situation is the same as ubiquitin. The protein-coding region of cesmt3b was 285 bp and deduced 95 amino acids. The amino acid identity of cesmt3b with hsmt3a, hsmt3b, hsmt3c were 91%, 96%, 45%, respectively. The transcribed size was 2.0 kb and was expressed in L2, L3, adult, dauer larvae stages. Northern blotting data showed additional 3.4, 8.0 kb hybridization signals were that supposed to be mRNA expression signals of cesmt3b fusion genes. The molecular weight of cesmt3b expressed fusion protein was 14 kDa. The expression of cesmt3b was inhibited by 12 hours taxol treatment at dauer larvae stage. This 3.4 kb signal also was disappeared after DMSO, heat shock, taxol, PAsO, nocodazole, vinblastine treatment. Another fragment was amplified by PCR method based on the sequence data of hsmt3a. The DNA sequence was submitted to BLAST search program and shown identity to a gene that is similar to ETS family oncoprotein DNA binding domain. Both cesmt3b and ETS-like fragment might play important roles in mitosis, microtubule integrity, centromere / kinetochore structure maintenance mechanisms.
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Chou, Yu-Huai, and 周玉懷. "The interactions between Human SMT3 families and Daxx detected by yeast two-hybrid assay." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/94896531474525857457.
Full textAbstract:
碩士<br>國立中山大學<br>生物醫學科學研究所<br>89<br>Abstract
SMT3 (Suppressor of MIF2 3 protein) was identified as a mutation
suppressor in yeast centromere protein MIF2. It is also known as an
ubiquitin-like protein due to the smilarities of their primary structures that
is very conserved during the eukaryotic evolution. Although only one
SMT3 was found in low eukaryotes such as in yeast, three members of
SMT3 (SMT3A, SMT3B and SMT3C) have been identified in high
eukaryotes. It has been known that SMT3C plays an important role in post-translational modification. However, the functions of SMT3A and SMT3B are not well studied yet and the relationship among the SMT3 families remains unclear.
In the present study, Daxx, a Fas binding protein, was demonstrated to bind to SMT3B using yeast two-hybrid assay. It was found that the
N-terminal domain of Daxx (Daxx 1) and the C-terminal domain of Daxx
(Daxx 4), respecifitively, bound to all members of human SMT3
families (including SMT3A, SMT3B and SMT3C). Neverthless,
mechanisms of interactions between the SMT3 families and Daxx
domains remined unclear. Studies on truncated human SMT3 families
have shown that two glycines on the C-terminal end of human SMT3
families were required in the interaction between SMT3 and Daxx
domains, for example, SMT3A and SMT3B required C-terminal two glycines on the Daxx 4 domain where as SMT3C required C-terminal two glycines on the Daxx 1 domain. Morever, truncated SMT3C and Daxx 1 domain point mutations have also indicated that the the linkage of
glycine97 of SMT3C and the lysine60 of Daxx 1, in which the SMT3C/
SUMO-1 consensus sequence ΨKXE was found. Further, SMT3C was
the only member of the SMT3 families capable of self-reacting.
Results also suggested that similar mechanism of interaction
between SMT3A/B and Daxx 1, which is not in accordance with the model proposed in this study regarding the interaction mechanism between SMT3C and Daxx 1. Although two glycines on the C-terminal end of SMT3A/B were necessary for the interactions with Daxx 4 domains, the SMT3C/SUMO-1-consensus sequence ΨKXE was not detected in the Daxx 4 domain. It is therefore, suggested that the mechanism of the interaction between SMT3A/B and Daxx 4 is similar to that of SMT3C and Daxx 1, that may required different binding sequences that is specific for SMT3A/B.
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WU, Chun-Sen, and 吳春森. "Study on luminescent and packaging properties of Sm3+ doped phosphate phosphor." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/02830397808865659237.
Full textAbstract:
博士<br>國立高雄第一科技大學<br>工程科技研究所<br>102<br>Considering blue LEDs emit light with a wavelength is shorter than the green ones, it is possible to excite a suitable and intense yellow light-emitting phosphor which is complemented into the blue emission, and then a yield ideal white light is created. Out of all the phosphor LEDs involved, Ce doped yttrium-aluminate-garnet phosphor was found to be the most suitable satisfactorily tested on GaN LEDs for the production of white light. Recently, because of the high power LED growth, its driving current is increased, therefore heat problem is become a main issue, and will affect luminous efficiency. In order to overcome the above shortcomings, it is necessary to take a way to improve the conversion efficiency and thermal stability simultaneously. Regarding the heat problem, the phosphate oxide compound ( ABPO4，A=Li+, Na+, K+, Rb+, Cs+，B=Mg2+, Ca2+, Sr2+, Ba2+ ) as the host lattice of covalent nature of the phosphor with three dimensional rigid structure. The phosphate oxide is very suitable for carrier transport, and the thermal stability of the phosphate series is quite outstanding. Using phosphate as host lattice in the phosphor material can solve the thermal problem of the high power of white LED in effective way.
In this study, KSrPO4’s phosphate structure is selected as the host lattice and Sm is chosen as the flux. Instead of the traditional sintering method, KSrPO4:Sm3 phosphate is made by using microwave assisted sintering technique, and then the microstructure, material and photo-luminescent properties of phosphate are investigated. The experiment results show that KSrPO4:Sm3+ phosphors have a uniform particle size distribution, and the excitation and emission spectra of the KSrPO4:Sm3+ phosphors indicate that they can be effectively excited by a NUV LED chip, and emit mainly at the 599 nm red wavelength, when sintering temperatures was increased to 1200°C from 1000°C, significant change in the morphologies and increase in particle size. When the sintering temperature was increased to 1300°C, a liquid phase sintering results in abnormal grain growth.
Moreover, several fluxes were used to improve the sintering process and to enhance the photo-luminescent properties in phosphor. In this study, NH4Cl is also adopted as fluxes to synthesis KSrPO4:Sm3+ phosphors. The experiment result shows that the emission intensity of KSr0.99PO4:0.01Sm3+ phosphors with 2 wt. % NH4Cl flux is also enhanced when the sintering temperature climbed to 1150°C from 1050°C and the maximum degree is at 1150°C, but the photo-luminescent is decreased dramatically when the sintering temperature was increased to 1200°C.
In the last part of this study, the optimal parameter for phosphor of KSrPO4:Sm3+ red phosphate is chosen and packaged it into the LED. The experimental results presented that the thermal quenching temperature T50 of the prepared KSr0.99PO4:0.01Sm3+ phosphor is 300°C and the phosphor could be successfully applied in LED.
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楊適存. "The preparation and photoluminescence of Y2O3 phosphors doped Eu3+ and Sm3+ ions." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/90331068833081839777.
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SINGH, SARVJEET. "SYNTHESIS AND PHOTOLUMINESCENCE PROPERTIES OF SM3+DOPED KMGPO4 PHOSPHORS FOR WHITE LIGHT EMITTING DIODES." Thesis, 2017. http://dspace.dtu.ac.in:8080/jspui/handle/repository/16059.
Full textAbstract:
Sm3+- doped KMgPO4 was prepared by high-temperature solid-state reaction having exceptionally bright and stable photoluminescence in the orange (602 nm) region of the electromagnetic spectrum. The X-ray powder diffraction, photoluminescence (PL) emission, and excitation spectra were thoroughly measured. The PL spectra of prepared KMgPO4 phosphor showed characteristic Orange emission when excited by 402 nm under UV excitation. The highest emission intensity was found for KMgPO4:xSm3+ with a composition of x=0.0075 Sm3+ ions and this phosphor used for remaining studies. The photoluminescence at room temperature shows broad orange 5d-4f emission bands are peaked at 602 nm and only two weak Sm3+ emission band is observed at 565 nm and 652 nm respectively. The phosphor was found to be superior in terms of integrated PL intensity, degradation resistant and markedly superior properties as compared to its counterparts. The objective of this dissertation is to synthesize the KMgPO4 phosphor and study the photoluminescence properties of the KMgPO4 phosphor doped with Sm3+ ions. These results can be used in the white LED for improved performance and stability. Further different characterization techniques used in the study of KMgPO4 such as photoluminescence, SEM, XRD and FTIR. The thesis has been divided into the various chapters. In chapter 1, Introduction for the research have been explained in brief. In chapter 2, different instrumentation used in the experimental work and synthesis of KMgPO4 phosphor have been discussed. In chapter 3, the characterization of the prepared samples have been explained. The conclusion and future
iv
work have been explained in chapter 4. Finally, all the references used in the research have been mentioned in the last.
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"Part I. Coordination chemistry of SmI3 with donor solvents: Part II. Synthesis and structural characterization of lanthanacarboranes." 1997. http://library.cuhk.edu.hk/record=b5889217.
Full textAbstract:
by Ka-yue Chiu.<br>The "3" in the title is subscript.<br>Thesis (M.Phil.)--Chinese University of Hong Kong, 1996.<br>Includes bibliographical references (leaves 103-110).<br>ACKNOWLEDGEMENTS --- p.3<br>ABBREVIATIONS --- p.4<br>ABSTRACT --- p.5<br>Chapter I. --- COORDINATION CHEMISTRY OF SmI3 WITH DONOR SOLVENTS --- p.7<br>Chapter 1.1. --- Introduction --- p.7<br>Chapter 1.2 --- Results and Discussion --- p.21<br>Chapter 1.2.A --- Synthesis and Structural Characterization of [trans-SmI2(THF)5][trans- SmI4(THF)2] (1) --- p.21<br>Chapter 1.2.B --- Synthesis and Structural Characterization of SmI3(DME)2 (2) --- p.26<br>Chapter 1.2.C --- Synthesis and Structural Characterization of [{Sm(H20)3}2{Sm(CH3CN) (H20)3}2{Sm(CH3CN)3(H20)}2(μ3-OH)8(μ6-0)]I8-2H20 (3) --- p.30<br>Chapter 1.3 --- Conclusion --- p.38<br>Chapter 1.4 --- Experimental Section --- p.39<br>Chapter II. --- SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF LANTHANACARBORANES --- p.45<br>Chapter II.1 --- Introduction --- p.45<br>Chapter II.2 --- Results and Discussion --- p.51<br>Chapter II.2.A --- Synthesis and Characterization of closo-Lanthanacarboranes --- p.51<br>Chapter II.2.A.i --- Sandwich Type Complexes --- p.51<br>Chapter II.2.A.ii. --- Half-Sandwich Type Complexes --- p.62<br>Chapter II.2.B --- Synthesis and Characterization of an exo-nido-Samaracarborane --- p.71<br>Chapter II.2.B.i. --- Synthesis and Characterization of an exo-nido-[{(C6H5CH2)2C2B9H9} Sm(DME)2]2.DME(18) --- p.77<br>Chapter II.3 --- Conclusion --- p.84<br>Chapter II.4 --- Experimental Section --- p.85<br>REFERENCES --- p.99
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Kao, Wei-jung, and 高瑋嶸. "Investigation on structure and photoluminescence of ZrO2:Sm3+ produced by RF sputtering deposition." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/33734916556974523588.
Full textAbstract:
碩士<br>國立成功大學<br>材料科學及工程學系碩博士班<br>97<br>There is a global energy shortage problem, so we must try to invent a
energy-saving and environment friendly lighting product. LED is a ideal one.
White light LED is composed of different color light. The presupposition of
high luminescence efficiency is a host with low phonon energy, just like ZrO2.
Sm is a rare-earth element and its emission wavelength range is from yellow
to red light. We’re looking for a great procedure for high efficiency.
According to previous research, we use RF-sputtering because of less process
of RF sputtering.
The best oxygen concentration for experiment was 2%. We used 0.33at%
0.46% 1.48% 2.19% of Sm3+ as model. The highest luminescence efficiency
concentration was 0.33at%.
When the dopant concentration was changed, Monoclinic and Tetragonal
had different effect on 574nm、575nm、622nm. The rest of emission peak
were contributed to Monoclinic.
Key word：RF sputtering、Sm、Monoclinic
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Cheng, Tzu-Chieh, and 鄭資頡. "Study of High-Brightness White Light Point SourceUsing Ce3+,Sm3+:YAG Crystal Fiber." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/73386989906862473278.
Full textAbstract:
碩士<br>臺灣大學<br>光電工程學研究所<br>98<br>In 2009, the newly inaugurated U.S president Barack Obama has proposed an energy-environment strategic plan focusing on the development of “inexpensive, clean, and highly-efficient energy.” At the same time, the leading countries worldwide are also rising the importance of solid-state lighting research to a national military strategic level, which is aimed at creating an eco-friendly and highly-efficient lighting business. It is estimated that by the 2020, solid-state lighting will be able to save 11% of global energy plus 259 million tons of carbon dioxide emission each year, which is equivalent to saving an expenditure of US$112 billion yearly. Therefore, the field of high-brightness solid-state lighting research has gradually evolved as a mainstream subject of the green-energy industry.
This thesis studies the thin-layers-coating of CeO2 and Sm2O3 on the circumference of pure YAG crystal fiber, and the regrow of coated samples into Ce3+,Sm3+:YAG crystal fibers with 10 μm-diameter core by LHPG method. Referring to present mechanism regarding the color blending of high-brightness white LED, which is formed by combining blue LED with yellow phosphors, this study uses blue laser diode of 446 nm center wavelength as exciting light source, and uses objective lens to focus the laser on crystal-fiber. By the core-excited method, the mechanism can excite Ce3+ and Sm3+ ions and generate yellow broad-band ASE light of 98 nm 3dB bandwidth, which on the one side serve as the light source for high-resolution low Optical Coherence Tomography (OCT) with its axial resolution up to 1.5 μm, and is expected to have great contribution on cell-pathological-changes detection as well as LCD’s pretilt angle measurement; and on the other side will blend with residuary blue light and turn into white light with its brightness close to Ultra-high-Pressure (UHP) mercury lamp at highest brightness level of 100M~1G cd/m2 and chromaticity coordinates of (0.3022,0.3335) nearly at the center of the chromaticity diagram. In addition, according to the measurement results of small-signal gain experiment, Ce3+,Sm3+:YAG crystal fiber can create 5.47 dB gain of -29.33 dBm signal at 100 mW exciting power. For future research perspective, by using AR coating for exciting light source and HR coating at wavelength near 532 nm, it is possible to form laser resonator, which can achieve the development of Ce:YAG crystal fiber laser, or the development of green-band optical amplifier.
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Lin, Yu-De, and 林育德. "Expressing the SM1 gene of Trichoderma in tobacco and studying its antimicrobial activity." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/61095395824420428911.
Full textAbstract:
碩士<br>國立東華大學<br>生命科學系<br>100<br>Trichoderma spp. has been widely used as a biocontrol agent. Recent studies showed that Trichoderma spp. produce a small protein (SM1) that acts as an elicitor to trigger the resistance reactions of the colonized plants. Past studies have shown that SM1 is essential to trigger ISR (systemic resistance induced systemic resistance) in cotton, purified SM1 can induce cotton performance of the defense system against the pathogen of Colletotrichum graminicola and SM1 for the defense system to stimulate the corn is very effective. We believe that ThSM1 protein may have the activity of elicitor to trigger resistance reaction of colonized plants against pathogen infection. The purpose of this study is to elucidate the antimicrobial activity of ThSM1 protein in transgenic tobacco. The ThSM1 cDNA was constructed into the pCAMBIA vector and transformed into tobacco by Agrobacterium-mediated transformation. The N-terminus of the ThSM1 was fused to a signal peptide of thaumatin-like protein (TLP). Expression of the transgenes in transgenic tobacco was examined by PCR analysis and Real-time RT-PCR analysis. After antibiotic selection and regeneration, four transgenic tobacco plants were obtained. PCR analysis displayed the existence of transgenic gene TLPThSM1 in all the transgenic tobacco. Real-time PCR analysis of transgenic plants revealed differential expression levels of the transgene in transgenic tobacco. However, the transgenic tobacco plants showed no obvious antimicrobial activity against pathogenic bacterium, Ralstonia solanacearum, or pathogenic fungi, Rhizoctonia solani and Sclerotinia sclerotiorum. We speculated that it might be due to different post-translational modification of the transgenic protein or formation of ThSM1 dimers.
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Ajam, Tahereh. "Investigation of Structure and Function of Esco1 and Esco2 Acetyltransferases." Doctoral thesis, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E522-F.
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Casey, Aaron Edward. "Investigating the organisation of the platypus sex chromosome chain during meiotic prophase I." Thesis, 2015. http://hdl.handle.net/2440/96834.
Full textAbstract:
Meiosis is a specialised form of cell division that occurs specifically in the gonads of sexually reproducing species. It comprises a round of DNA replication followed by two successive rounds of cell division to produce haploid gametes. Each stage is divided into four substages of prophase, metaphase, anaphase and telophase. Prophase I is the longest and most complex stage of meiosis during which homologous chromosomes pair and recombine. The evolution of heteromorphic sex chromosomes has led to a number of changes in meiotic organisation. This includes the non-pairing of sex specific parts of the heteromorphic sex chromosomes and their inactivation in many species. The platypus has a unique set of 10 sex chromosomes with homology to bird sex chromosomes that exist as a chain during meiotic metaphase I. Questions of mode and extent of pairing and the existence of meiotic silencing remained unknown but can inform our understanding of the evolution and mechanisms of meiotic prophase I. Work presented in this thesis provides novel insights into evolution and meiotic organisation of the monotreme sex chromosome complex. The platypus sex chromosome chain forms during zygotene in stepwise manner, with remarkable consistency beginning at the Y5 end of the chain and ending with the X1 (Chapter 1). Synapsis generally relies on 3 main proteins; SYCP1, SYCP2 and SYCP3. Surprisingly platypuses express three different copies of SYCP3 (including a multicopy version on a Y chromosome), genes that generally exist as single isoforms in most other species. Particularly given the SYCP3Y isoform is male specific, this raises the possibility that SYCP3 paralogs may have evolved in relation to the sex chromosome chain during prophase I (Chapter 2). During pachytene, the asynaptic regions of the sex chromosomes adopt a state of folding, similar to that of the avian Z and W chromosomes during synaptic adjustment, albeit without the formation of a central element. During this time the cohesin complex is heavily loaded onto the axial elements of the asynaptic regions of the X and Y regions of the chain. Furthermore at mid-pachytene the asynaptic regions of the chain are pulled to a giant nucleolus at which time the cohesin appears to spread onto the chromosome loops of the asynaptic regions of the chain that are also coincident with DNA condensation (Chapter 3). During platypus pachytene there is global transcriptional downregulation. We observe no localised phosphorylation of the histone H2AX, a hallmark of MSCI but we do observe localised patterns of H2AFY, H3K27me3 and H3K9me3 at a paranucleolar location, however the H2AFY and H3K27me3 showed some colocalisation with sex chromosomes, there was not consistent pattern and H3K9me3 was always associated with a section of chromosome 6 (Chapter 4). Together these results provide novel insights into the meiotic organisation of the monotreme sex chromosome complex and the evolution of MSCI in mammals.<br>Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2015