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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Expressão dos genes codificadores de canais de sódio Nav 1.7, Nav 1.8 e Nav 1.9 em portadores da Síndrome de Ardência Bucal / Expression of coding genes sodium channel Nav 1.7, Nav 1.8 and Nav 1.9 in patients with Burning Mouth Syndrome

Vanessa Juliana Gomes Carvalho 20 January 2016 (has links)
A síndrome de ardência bucal (SAB) é uma condição caracterizada pelo sintoma de ardência na mucosa oral, na ausência de qualquer sinal clínico. Sua etiologia é desconhecida e, até o momento, não dispõe de tratamento efetivo. Há entretanto características de doença neuropática que justificam investigações nesse sentido. O objetivo desse estudo foi mensurar a expressão gênica dos receptores de canais de sódio, Nav 1.7, Nav 1.8 e Nav 1.9, nos pacientes portadores de SAB. A casuística foi composta por dois grupos sendo o grupo de estudo composto por 12 pacientes portadores de SAB, selecionados através do critério estabelecido pela International Headache Society, em 2013 e o grupo controle composto por 4 pacientes não portadores de SAB. As amostras analisadas foram coletadas do dorso lingual, por meio de biópsia realizada com punch de 3 mm e profundidade de 3 mm, estas foram submetidas ao método de análise RT-PCR em tempo real. A expressividade dos genes de canais de sódio foi avaliada nos indivíduos portadores de SAB em relação aos do grupo controle, sendo esta calculada a partir da normalização dos dados da quantificação destes com os da expressão do gene constitutivo (GAPDH), pelo método de Cicle Threshold comparativo e analisados estatisticamente por meio do teste estatístico Mann-Whitnney. Observou-se o aumento da expressão gênica do Nav 1.7 (fold-change = 38.70) e diminuição da expressão gênica do Nav 1.9 (fold-change = 0.89), porém sem diferenças estatisticamente significativas entre os grupos analisados. O gene Nav 1.8 não foi expresso em nenhuma das amostras analisadas. O Nav 1.7 expressa-se tanto em neurônios nociceptivos quanto no sistema nervoso autônomo e mutações no Nav 1.9 tem sido associada a perda de percepção dolorosa. Os resultados obtidos embora não estatisticamente significativos são compatíveis com as características da doença, justificando a extensão dos estudos na linha expressão de genes codificadores dos canais de sódio em pacientes com SAB. / Burning mouth syndrome (BMS) is a condition characterized by symptoms of burning in the oral mucosa, in the absence of any clinical signs. Its etiology is unknown and so far, it has no effective treatment. It is important to mention that BMS exhibits some traits of a neuropathic disease, what justifies a thorough investigation of this subject.The objective of this study was to measure the gene expression of the sodium channel receptors, Nav 1.7, Nav 1.8 and Nav 1.9, in patients with BMS.The sample was composed of two groups, being the study group formed by 12 patients with SAB, selected according to the criteria established by the International Headache Society in 2013, while the compound control group had 4 patients without SAB. The analyzed samples were collected from the tongue, by the biopsy technique with a 3 mm punch and 3mm depth. These samples were processed in real time, following the guidelines set forth by the RT-PCR method. The expressiveness of the sodium channels was evaluated in the individuals with BMS in relation to control group, which was calculated from the normalization of these data with the quantification of the expression of a constitutive gene (GAPDH) by the Cycle Threshold comparative methods and statistically compared by Man-Whitnney test. We observed an increased gene expression of Nav 1.7 (fold-change = 38.70) and a decreased gene expression of Nav 1.9 (fold-change = 0.89), but no statistically significant differences between the groups. Nav 1.8 gene was not expressed in any of the samples. Nav 1.7 is expressed in both nociceptive neurons as the autonomic nervous system and changes in Nav 1.9 has been associated with loss of pain perception. The results although not statistically significant are consistent with the disease characteristics, justifying the extension line of the studies on the expression of genes encoding the sodium channel in patients with SAB.
222

Detecção e caracterização molecular do gene 3 e 5 do coronavírus de perus (TCOV) isolados de perus com severa enterite no Brasil. / Detection and molecular characterization of gene 3 and 5 of turkey coronavirus (TCoV) from turkeys with severe enteritis in Brazil.

Amarilis Novaes D'Elboux Bünger 26 August 2009 (has links)
O coronavírus de perus (TCoV) é o agente etiológico associado a síndrome de mortalidade entérica das aves (PEMS). PEMS é uma enfermidade entérica, aguda e altamente contagiosa dos perus caracterizada por depressão, anorexia, diarréia e alta mortalidade em lotes de perus comerciais. A presença do coronavírus de perus (TCov) foi pesquisada em 29 amostras de conteúdo intestinal de perus entre 10 e 104 dias de idade que apresentaram enterite severa no período de 2004 a 2006. A detecção do TcoV foi realizada realizada através da técnica da transcriptase reversa e da reação em cadeia pela polimerase (RT-PCR), mediante a amplificação da região 3 UTR, seguida pela amplificação dos genes 3 e 5. A caracterização molecular dos vírus foi realizada mediante a amplificação dos genes 3 e 5, que mostrou similaridade genética entre as amostras, mas diferenças com as sequencias dos outros TCoVs publicados previamente. Em relação ao gene 3, as amostras apresentaram maior relação com o vírus da bronquite infecciosa das aves (IBV), enquanto que com o gene 5 houve maior identidade com os cronavírus de faisão (PhCoV). Nossos resultados sugerem que a estratégia de amplificação da região 3 UTR provou ser uma estratégia eficaz para a detecção do TcoV em conteúdo intestinal. / Turkey coronavirus (TCoV) is causative agent associated to Poult Enteritis and Mortality Syndrome (PEMS) in turkeys wideworld. The disease is characterized by an acute highly contagious enteric disease of turkeys characterized by depression, anorexia, diarrhea and high mortality in co mMercial turkey flocks. The presence of turkey coronavirus (TCoV) in 29 intestinal content samples from turkey flocks aged between 10 and 104 days with severe enteritis was monitored in the period of 2004 to 2006. TCoV detection was accomplished by the reverse transcriptase-polymerase chain reaction (RT-PCR), through amplification of the 3´UTR region, followed by amplification of genes 3 and 5. Molecular characterization of the viruses was done through amplification of genes 3 and 5, and showed evidence of genetic similarity between them, although they differed of sequences of other TCoVs described in the literature. In relation to gene 3, samples showed greater relationship with chicken infectious bronchitis virus (IBV), and while gene 5 showed greater identity with pheasant coronavirus (PhCoV). Our results suggest that the strategy of amplification of the 3´UTR region has proved to an effective means of detection of TCoV in intestinal contents.
223

Effect of plant growth regulator applications on phenolic quality of red grape berry skin and wine Vitis vinifera L., cvs Cabernet Sauvignon and Carmenère / Effet de l'application des régulateurs de croissance végétale sur la qualité phénolique de la pellicule du raisin et du vin rouge Vitis vinifera L., cépages Cabernet Sauvignon et Carmenère

Gonzalez Rojas, Alvaro 30 May 2012 (has links)
La composition phénolique du vin rouge détermine fortement sa qualité: couleur, goût, texture et la plupart des bienfaits pour la santé. Les conditions ambiantes de la vigne modulent l'équilibre hormonal endogène et l'expression de gènes qui contrôlent la voie de synthèse des composés flavonoïdes, en déterminant la composition phénolique finale du raisin. Même s'ils ont été étudiés, les effets des applications des régulateurs de croissance végétale sur l'équilibre hormonal endogène et la qualité du raisin, les effets de ces substances sur la composition et la qualité du vin sont pauvrement documentés. Le traitement des raisins destinés à la vinification avec des régulateurs de croissance végétale est un outil potentiel pour modifier la qualité des raisins et du vin rouge. Ce projet de thèse a pour objectif d’étudier l’impact d'applications de régulateur de croissance végétale sur la composition phénolique des raisins de Vitis vinifera L. cépages Cabernet Sauvignon et Carménère. L’acide abscissique, l’acide indole-3-acétique et l'acide 2-chloroethilphosphonique ont été appliqués à divers stades phénologiques du raisin, doses et conditions environnementales: Les essais ont été menés à Maipo et Cachapoal au Chili et à Bordeaux en France, dans des vignobles commerciaux et expérimentaux ainsi que sur des plantes cultivées en pots. Il a été examiné l'effet de ces traitements sur le contenu interne d'hormones, sur l'expression de gènes structuraux et régulateurs de la synthèse de composés flavonoides et sur la qualité des raisins, en particulier la composition phénolique de sa pellicule. De plus, des vinifications ont été réalisées à partir de raisins traités pour déterminer l'effet des traitements sur la composition chimique et phénolique du vin, ainsi que sur des attributs qualitatifs tels que les arômes et la texture des vins, jugés par un panel d'évaluation sensorielle. / Phenolic composition strongly determines red wine quality: color, taste, texture and most health benefits. Vineyard environmental conditions modulate endogenous hormonal balance and gene expression which control the flavonoid biosynthetic pathway leading to final grape phenolic composition. Even when the effects of plant growth regulator applications on grape endogenous hormonal balance and quality have been studied, the effect of these substances on wine composition and quality is poorly documented. The treatment of wine grapes with plant growth regulators is a potential tool in order to modify red wine phenolic composition and quality. This thesis project describes six experiments on plant growth regulator applications on developing grapes of Vitis vinifera L., cvs Cabernet Sauvignon and Carménère. Abscisic acid, Indole-3-acetic acid and 2-chloroethylphosphonic acid were applied in different phenological stages, doses and environmental conditions: Maipo and Cachapoal regions in Chile and Bordeaux region in France, commercial and experimental vineyards and plants in containers. The effect on changes in the internal hormonal content, expression of flavonoid biosynthetic and regulatory genes and grape quality, in particular grape skin phenolic composition were examined. In addition, winemaking was performed in order to assess the effect of treatments on wine chemical and phenolic composition and on wine aroma and texture attributes judged by a sensory panel.
224

Diversidade genética da neuraminidase de vírus Influenza A, isolados de crianças internadas na cidade de São Paulo, de 1995 a 2006. / Genetic diversity of Neuraminidase of Influenza A virus, isolated from children hospitalized in São Paulo city, from 1995 to 2006.

Patricia Rossi do Sacramento 14 May 2010 (has links)
O presente estudo teve por objetivos caracterizar os vírus Influenza circulantes na cidade de São Paulo e verificar a variabilidade genética do gene da neuraminidase (NA) dos Influenzavírus A. Um total de 3009 amostras de crianças internadas no Hospital Universitário da USP, no período de 1995 a 2006, foram submetidas à duplex RT-PCR para detecção dos Influenzavírus A e B (IA e IB). As amostras positivas para IA foram submetidas à subtipagem pela multiplex RT-PCR. Cento e trinta e três amostras (4,4%) foram positivas, sendo 88,0% (117/133) IA e 12,0% (16/133) IB. Entre as amostras IA, 94 eram H3N2, 7 H1N1 e 16 não foram subtipadas pela multiplex. Um total de 74 amostras (71 H3N2 e 3 H1N1) tiveram o gene da neuraminidase sequenciado (total ou parcialmente). As sequências obtidas foram submetidas à análise filogenética, sendo verificado o agrupamento das cepas circulantes em clusters por ano de isolamento, demonstrando sua evolução temporal. Quando comparadas com as cepas vacinais utilizadas no período, foi verificada uma boa similaridade. / The aim of this study was to characterize Influenza virus circulating in São Paulo city and the neuraminidase (NA) gene sequence of Influenzavirus A in 3009 samples from children hospitalized at USP University Hospital, from 1995 to 2006. Samples underwent duplex RT-PCR for detection and typing of Influenza virus A and B (IA and IB) and also were submitted to multiplex PCR for subtyping of IA. Among 3009 samples, 4.4% were Influenza virus, being 88.0% IA (117/133) and 12.0% IB (16/133). Among samples of IA, 94 were characterized as H3N2, 7 H1N1 and 16 were not subtyped. A total of 74 samples (71 H3N2 and 3 H1N1) had the NA gene sequenced (total or partially). Sequences obtained were compared to sequences of the world and sequences of vaccine strains. Brazilian samples were grouped in clusters with samples isolated in the same year. It was also found a good similarity between circulating strains and vaccine strains.
225

Prisustvo i raširenost virusa životinja i ljudi u površinskim vodama Vojvodine / Presence and prevalence of animal and human viruses in surface water in Vojvodina Province

Lazić Gospava 22 November 2016 (has links)
<p>Vi&scaron;e od 100 vrsta virusa ljudi i životinja se izlučuje u spolja&scaron;nju sredinu. Prisustvo ovih virusa u povr&scaron;inskim vodama reflektuje fekalnu kontaminaciju i ukazuje na<br />opasnost za zdravlje ljudi i životinja. Na području Srbije se ne prati prisustvo patogenih virusa u povr&scaron;inskim vodama, pa&nbsp; čak ni u vodama za piće, a nije uspostavljena&nbsp; ni&nbsp; metodologija ovih ispitivanja. Shodno tome, cilj disertacije je da se utvrdi i analizira prisustvo animalnih i humanih virusa u povr&scaron;inskim vodama primenom najsavremenijih metoda koncentrovanja i detekcije virusa. U okviru disertacije ispitano je prisustvo sledećih virusa u povr&scaron;inskim vodama na teritoriji Vojvodine: humanih adenovirusa (HAdV); norovirusa (NoV) i hepatitis A virusa (HAV), adenovirusa svinja (PAdV),&nbsp; poliomavirusa goveda (BPyV) i hepatitis E virus (HEV).</p><p>Ispitano je ukupno 108 uzoraka povr&scaron;inskih i otpadnih voda koji su prikupljani od oktobra 2012. godine do juna 2014. godine. U radu su primenjene najsavremenije metode koncentrovanja i detekcije virusa u vodi, koje se u Srbiji nisu koristile za ovu namenu. Sprovedenim ispitivanjima dokazano je da su animalni i humani virusi prisutni u povr&scaron;inskim vodama na području Vojvodine. Najče&scaron;će detektovan&nbsp; virus u povr&scaron;inskim vodama je humani adenovirus (42,4%), a potom norovirusi GII i GI (40,4% i 15,2%), adenovirus svinja (11,1%), poliomavirus goveda (7,1%) i hepatitis E virus (3,0%). U ukupno 9 testiranih uzoraka gradske kanalizacione vode najče&scaron;će je detektovan HAdV (44,4%), NoV GII i GI&nbsp; (66,7% i 22,2%), BPyV je detektovan u samo jednom od 9 uzoraka, a niti u jednom nisu detektovani PAdV i HEV. Hepatitis A virus nije detektovan u uzorcima, a eksperimentalno je potvrđeno da su metode primenljive i za detekciju ovog virusa. Na osnovu rezultata prinosa procesne kontrole i utvrđenog prisustva virusa u uzorcima,&nbsp; zaključeno&nbsp; je da se ove metode mogu veoma uspe&scaron;no koristiti za detekciju virusne kontaminacije&nbsp; povr&scaron;inskih voda. Izvr&scaron;ena je igenotipizacija virusa iz odabranih uzoraka metodom sekvenciranja dela virusnog genoma. Indirektno je potvrđeno da su infekcije&nbsp;&nbsp; detektovanim virusima prisutne u populaciji životinja i ljudi. Prisustvo virusa u&nbsp;&nbsp; povr&scaron;inskim vodama i uzorcima gradske kanalizacije odražava infektivni status stanovni&scaron;tva, ali predstavlja i značajan rizik za zdravlje životinja i ljudi na području koje gravitira ispitanim vodama.&nbsp;</p> / <p>Over 100 types of pathogenic viruses are excreted in human and animal wastes. The presence of human and animal pathogenic enteric viruses in water environments reflects fecal contamination and indicates a risk to public health.&nbsp; Republic of Serbia does not implement surveillance for the presence of pathogenic human and animal viruses in surface waters and even in drinking water, neither is the established methodology of these studies in any institution in Serbia.&nbsp; Accordingly, the aim of the study was to determine and analyze the presence of human and animal viruses in surface water,&nbsp; using the latest methods&nbsp; of&nbsp; concentration and detection of the viruses.&nbsp; Within the dissertation examined the presence of the following viruses in surface waters in Vojvodina:&nbsp; Human adenoviruses&nbsp; (HAdV), noroviruses (NoV)&nbsp; and hepatitis A virus), Porcine adenovirus (PAdV) and Bovine polyomavirus (BPyV)&nbsp; and&nbsp; Hepatitis E virus (HEV).<br />A total of 108 samples of surface water and waste water were collected from October 2012 to June 2014. The paper are applied the most advanced methods and the concentration of virus detection in water, which in Serbia are not used for this purpose. The conducted tests have proven that the animal and human viruses present in surface waters in Vojvodina. The most commonly detected virus in surface water was human adenovirus (42.4%), followed by Norovirus GI&nbsp; and GII (40.4% and 15.2%),&nbsp; Porcine adenovirus&nbsp; (11,1%),&nbsp; Bovine polyomavirus&nbsp; (7.07%) and hepatitis E virus (3,0%).<br />In total of&nbsp; nine analysed sewage samples human adenovirus was detected in 44,4%&nbsp; of&nbsp; samples. The prevalence of norovirus GII and GI in sewage&nbsp; samples was&nbsp; 66,7%&nbsp; and 22,2%. Bovine&nbsp; polyomavirus was detected in one of nine samples while porcine adenovirus and hepatitis E virus were not detected in any of analyzed samples.&nbsp; Hepatitis A virus was not detected in samples, but&nbsp; it has been experimentally confirmed that the methods applicable for detection of the virus. Based on the results of process control and yield determined the presence of virus insamples, it was found that these methods can be successfully used to detect viral contamination of surface waters. Also, in these study was performed genotyping of viruses from selected samples by sequencing a part of the viral genome. Indirectly it is confirmed that the infection detected viruses present in a population of animals and humans. The presence of virus in samples of surface water and urban sewage reflects the infectious status of the population, but also constitutes a significant risk to the health of animals and people in the area that gravitates with tested waters.</p><p>&nbsp;</p>
226

DEVELOPMENT OF MOLECULAR DIAGNOSTIC ASSAYS FOR EQUINE RESPIRATORY VIRUSES AND ANALYSIS OF THE ROLE OF EQUINE ARTERITIS VIRUS ENVELOPE PROTEINS IN THE EARLY EVENTS OF VIRUS ENTRY

Lu, Zhengchun 01 January 2012 (has links)
There is an urgent need for detection of viral respiratory pathogens to identify the causal agent(s) involved and to prevent the spread of related diseases. The first part of this dissertation focuses on development, optimization and validation of Real-time reverse transcription polymerase chain reaction (rRT-PCR) assays for the detection of several common equine viral pathogens: equine arteritis virus (EAV), equine influenza virus and equine rhinitis viruses A and B. Emphasis of the second part of this dissertation is on studying the role of EAV envelope proteins in virus attachment and entry. Using an infectious cDNA clone of EAV and reverse genetics, a panel of chimeric viruses was generated by swapping the N-terminal ectodomains and full-lengths of the two major envelope proteins (GP5 and M) from porcine reproductive and respiratory syndrome virus (PRRSV). The recombinant viruses expressing the N-terminal ectodomain of PRRSV GP5 or M or both (GP5ecto, Mecto, and GP5&Mecto, respectively) in an EAV backbone were viable and genetically stable. Compared to the parental virus, these three chimeric viruses produced lower titers and smaller plaque sizes indicating that they have a crippled phenotype. Interestingly, the three chimeric viruses could only infect EAV susceptible cell lines but not the PRRSV susceptible cell line. Therefore, the exchange of GP5 and/or M protein N-terminal ectodomains from PRRSV did not alter the cellular tropism of the chimeric viruses. We also investigated the role of one of the minor envelope proteins (E) of EAV in virus attachment and entry. The results showed that EAV infection of equine endothelial cells is heparin-dependent and the Cterminus of the E protein contains a putative heparin-binding domain. We generated a panel of arginine to glycine mutations in the conserved region of both the full-length EAV infectious cDNA clone and individual E protein expression vectors. The triple mutation R52,60,65G construct grew significantly slower and produced much smaller plaques. The double mutant R52,60G completely blocked the interaction between E protein and heparin. Taken together, these data indicated that E protein interacts with heparin to facilitate virus attachment and plays a major role in EAV infection.
227

The neuroanatomical  expression profile of novel  membrane proteins. : The effect of macronutrients on gene expression.

Malmberg, Jennie January 2008 (has links)
<p>Worldwide obesity is an increasing problem. Apart from the fact that obesity greatly  impairs the health, quality and length of life for the affected individuals, it is also has the  potential to become a major socioeconomic problem in a near future. However preventive  actions require an understanding of the cause. Before the psychological influence on  eating can be evaluated a profound understanding of the biological regulatory system and  how this interacts with the food consumed is required. On the assumption that food  consumption is regulated by interplay between food and genes, the food itself may  influence the genes that regulate consumption, hence change the expression levels of the  genes regulating food intake.     To evaluate the interplay between food and gene expression, the project contained several  parts, reflecting different aspects of the area of research. The feeding studies had in  common that they were initial trials in a larger project. The results of these will be  evaluated and used in combination with further studies.     The mice typed for food preference illustrate the complexity of the feeding regulatory  system by pointing out the differences between individuals even in a relatively small  group of animals. Mice in general like food high in fat and here the animals that showed a  preference for sugar also showed a significant increase in their intake of chow. Since  chow consists mainly of carbohydrates the results might indicate a preference not for  sucrose in particular but for carbohydrates in general. The effect this may have on other  studies is still unclear as further studies are needed to determine whether the difference  may be the result of an innate genetic difference.      Leucine has been previously shown to reduce the total caloric intake. When given in  combination with palatable food the addition of Leucine primarily reduced the intake of  chow. From a dietary perspective this would translate to a preference to sweets and fast  food at the expense of food with more nutritious content.     The RT-PCR analysis’s gives clues to how the energy regulatory circuitry responds to the  intake of selected macronutrients. When it comes to gene expression there is a significant  effect of macronutrients on the gene expression levels. The common theme for many of  the genes tested seems to be down regulation of satiety signals, as if to support over  feeding on palatable diets and in many cases sucrose in particular.     The intake of macronutrients such as sugar or fat has been showed to have an effect on  the feeding regulatory circuitry, demonstrated by the change in gene expression levels.   The response to said macronutrients is site specific which is clearly shown both by RTPCR analysis of samples from different parts of the brain, such as the brainstem or  hypothalamus, and by immunohistochemistry of selected areas. The  immunohistochemistry also confirms that the novel Oxytocin receptor-antagonist, who is  injected IP, actually passes over the blood-brain barrier and has an actual affect on the  regions of interest. The areas affected by the antagonist can be visualized and identified  through the staining of active sites.</p>
228

SYNTHESIS AND BIOLOGICAL EVALUATION OF CCR5 ANTAGONISTS AS NOVEL ANTI-PROSTATE CANCER AGENTS

Adams, Joanna Lee 01 January 2007 (has links)
The chemokine receptor CCR5 has been implicated in the pathogenesis of prostate cancer (PCa). A novel series of piperazine derivatives have been designed and synthesized as CCR5 antagonists and their activity as inhibitors of PCa cell lines proliferation was explored. A lead compound has been identified which induced 100% inhibition of PCa cell proliferation at micromolar concentrations. Anibamine, the only natural product CCR5 antagonist, was also examined for its anti-proliferative activity and was found to inhibit proliferation of PCa cells at micromolar concentrations as well. The expression of RANTES mRNA was observed in DU-145, M12 and P69 cells via RT-PCR, while the expression of CCR5 mRNA was observed only in M12 cells. A CHO-CCR5 stable cell line was prepared for the CCR5 ligand competition binding assays. Both anibamine and the newly identified lead compound will serve as leads in the development of novel CCR5 antagonists as anti-prostate cancer agents.
229

Sequenciamento parcial do vírus da pinta verde do maracujazeiro (Passion fruit green spot virus-PFGSV), desenvolvimento de métodos para sua detecção e estudos sobre sua variabilidade genética / Partial sequencing of the Passion fruit green spot virus (PFGSV), development of methods for the molecular detection and evaluation of the genetic variability of this virus

Luizon, Renata Antonioli 26 January 2010 (has links)
A cultura do maracujazeiro tem sido afetada por um grande número de pragas e doenças, que exigem dedicação e esforços urgentes, no sentido de minimizar as perdas e evitar sua disseminação. O vírus da pinta verde do maracujazeiro (PVM) (Passion fruit green spot virus PFGSV) caracteriza-se por induzir a formação de pequenas manchas verdes em frutos e em folhas, e lesões necróticas em ramos. Exames de secções ultrafinas de tecidos infectados ao microscópio eletrônico de transmissão consistentemente revelam a presença de partículas baciliformes em cisternas do retículo endoplasmático e viroplasma denso no citoplasma. Os efeitos citopáticos encontrados, a relação com o ácaro vetor, Brevipalpus phoenicis, e a comparação com outros vírus transmitidos por Brevipalpus (VTB), como o da leprose dos citros, classifica o vírus como sendo do tipo citoplasmático. Seu relato inicial deu-se há cerca de 10 anos em Vera Cruz-SP, mas em 1994 foi relatada uma doença no Estado da Bahia chamada de definhamento precoce do maracujazeiro (DPM), que apresenta sintomas, efeitos citopáticos e vetor semelhantes ao da pinta verde, tendo sido sugerida a possibilidade de serem duas denominações para uma mesma doença. Atualmente a PVM/DPM encontra-se em vários outros Estados como Minas Gerais, Rio de Janeiro, Sergipe, Rondônia, Maranhão, Rio Grande do Norte, Paraíba e Pará, além do Distrito Federal. Sua diagnose ainda depende dos sintomas observados, infestação por ácaros Brevipalpus e microscopia eletrônica. Para se desenvolver um método de diagnose molecular, que permita detectar o vírus causador da PVM/DPM de maneira rápida e confiável, em grande número de amostras, foi feita uma Biblioteca de cDNA a partir do RNA dupla fita do vírus, extraído de tecidos sintomáticos de maracujazeiros infectados com um isolado do PFGSV encontrado em Limeira-SP. Com o sequenciamento parcial do genoma viral, foram desenhados primers específicos que amplificam partes dos genes putativos da p24 e aqueles que codificam a proteína de movimento (MP) e a Replicase (Rep) de diferentes isolados do PFGSV. Primers do PFGSV e de dois outros VTBs do tipo citoplasmático (VTB-C) para os quais se dispõe de primers para sua detecção por RT-PCR (vírus da leprose dos citros C - CiLV-C; mancha anelar de Solanum violaefolium - SvRSV) foram testados em reações homólogas e heterólogas. Ocorreram amplificações por RT-PCR gerando fragmentos de tamanho esperados apenas para os vírus homológos, mas não nas reações heterólogas, indicando que PFGSV deve diferir do CiLV-C e SvRSV. Assim, tem-se agora uma ferramenta molecular que detecta especificamente o PFGSV. Um estudo inicial sobre a variabilidade genética do PFGSV foi feito a partir da extração do RNA total, seguido de RT-PCR utilizando os primers específicos, purificação dos fragmentos obtidos e uso da técnica de Single Strand Conformational Polymorphism (SSCP). Foram analisados isolados procedentes de diferentes regiões brasileiras e em geral a variabilidade foi maior para as amostras do Estado de São Paulo. Logrou-se transmitir experimentalmente o PFGSV com ácaros para uma espécie silvestre de maracujá (Passiflora morifolia). / In Brazil, passion fruits are affected by several diseases and pests which affect their yield. Among them, a recently recognized viral disease, caused by Passion fruit green spot virus (PFGSV), is characterized by the presence of green spots on fruits and senescent leaves, and necrotic lesions on branches. When the infection is early, stem lesions may coalesce, girdling the branch resulting in the subsequent death of the plant. Electron microscopic examination of the thin sections of infected tissues revealed the presence of short, bacilliform particles in the cistern of the endoplasmic reticulum and dense, vacuolated viroplasma in the cytoplasm. The disease was shown to be transmitted by the mite Brevipalpus phoenicis (Acari: Tenuipalpidae). The localized symptoms, transmission by Brevipalpus mite and the observed cytopathic effect are considered evidences to demonstrate the viral nature of the disease and place it among the socalled cytoplasmic type of Brevipalpus-transmitted viruses (C-BTV), whose prototype is the Citrus leprosis virus C (CiLV-C). Though the first report of the disease occurred more than 10 years ago at Vera Cruz-SP, little is known about PFGSV, though it has been found in several passion flower growing areas in Brazil. In 1994 was report a disease named of DPM (definhamento precoce do maracujazeiro) was reported state of Bahia, with characteristics similar to that of the PVM and it has been suggested that DPM and PVM are the same disease. Subsequently the PVM/DPM has been found in several others Brazilian States as Minas Gerais, Rio de Janeiro, Sergipe, Rondônia, Maranhão, Rio Grande do Norte, Paraíba, Pará and Distrito Federal. Diagnosis has been made by symptoms, association with Brevipalpus mites and the time consuming transmission electron microscopy. This work reports the results of efforts to generate a quick and precise method to detect the virus for the diagnosis of the disease, evaluate the variability of the PFGSV isolates from different regions of the country and determine the taxonomic position of this virus. From the dsRNA present in extracts of the PFGSV-infected passion flower plant tissues, a cDNA library was obtained and its sequencing permitted to identify part of the viral genome. Based on these sequences, particularly of p24 and the putative genes that code for the movement protein (MP) and replicase (Rep), specific primers were designed which specifically detected PFGSV by RT-PCR in extracts of PFGSV-infected tissues. Evaluation of the variability of different isolates of PFGSV was made by single strand conformational polymorphism (SSCP) of the amplified fragments of the viral genome. In general, it a larger variation was found in isolates from São Paulo state. PFGSV seems to differ from two other C-BTV with available primers, CiLV-C and the Solanum violaefolium ringspot virus (SvRSV), since RT-PCR assays do not cross amplify their genomes. Experimental transmission of PFGSV by mites to woodland passion flower (Passiflora morifolia) was achieved.
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Zucchini lethal chlorosis virus (ZLCV): detecção, avaliação de danos em abobrinha de moita e reação de espécies de cucurbitáceas / Zucchini lethal chlorosis virus (ZLCV): detection, evaluation the damage on zucchini squash and the reaction of species of cucurbits

Giampan, José Segundo 31 August 2007 (has links)
O Zucchini lethal chlorosis virus (ZLCV) é uma espécie do gênero Tospovirus, transmitido por tripes, que infecta diversas espécies da família Cucurbitaceae. Já foi constatado em diversos estados brasileiros e sua incidência tem aumentado significativamente nos últimos anos em algumas regiões. Por se tratar de uma virose em potencial para as cucurbitáceas, pouco se conhece sobre os danos causados e a reação das diferentes espécies de cucurbitáceas à infecção em campo. Esse trabalho teve por objetivos: estudar a eficiência da RT-PCR para a detecção rápida e especifica do ZLCV em cucurbitáceas; avaliar os danos causados pelo ZLCV em abobrinha de moita em campo e a reação de sete espécies/variedades de cucurbitáceas à infecção natural A detecção do ZLCV por RT-PCR foi estudada utilizando um par de oligonucleotídeos iniciadores, desenhados com base na seqüência do S-RNA do ZLCV (AF067069). Quatro espécies de tospovírus (TSWV, TCSV, GRSV e CSNV) e outros vírus que infectam cucurbitáceas (PRSV-W-1, PRSV-W-C, ZYMV-M, ZYMV-Atibaia e CMV) foram incluídos no teste. Na reação de RT-PCR foi obtido um fragmento de aproximadamente 350 pb, amplificado somente a partir de RNA total extraído de planta infectada com o ZLCV. A seqüência obtida desse fragmento apresentou 98,2 % de identidade com a seqüência de nucleotídeos do S-RNA do ZLCV depositada no GenBank. Os danos causados pelo ZLCV em abobrinha de moita &#39;Caserta&#39; foram avaliados em campo na ESALQ/USP, Piracicaba-SP, onde esse vírus é freqüente. As plantas foram monitoradas semanalmente quanto à infecção pelo ZLCV por meio dos sintomas e por PTA-ELISA. As plantas foram agrupadas em função da época de aparecimento dos sintomas do ZLCV, avaliando a produção de frutos comerciais (FC) e não comerciais (FNC) de cada grupo e comparando com a de plantas que permaneceram sem sintomas até o final do experimento. As plantas que apresentaram sintomas até os 23 dias após a emergência (DAE) não produziram qualquer tipo de frutos. FC foram colhidos de plantas que apresentaram sintomas a partir dos 42 DAE. Mesmo assim, houve redução de 78,5 % na produção de FC. Plantas que mostraram sintomas por ocasião da última colheita (55 DAE) apresentaram redução na produção de FC de 9,6 %. A infecção com o ZLCV até o início da frutificação inviabiliza a produção de FC de abobrinha de moita &#39;Caserta&#39;. A reação de sete espécies/variedades de cucurbitáceas à infecção com o ZLCV foi avaliada em campo, por meio da infecção natural e em casa de vegetação, onde as plantas foram duplamente inoculadas mecanicamente com o ZLCV no estádio cotiledonar. A avaliação foi feita com base no monitoramento dos sintomas e por PTA-ELISA. A abobrinha de moita &#39;Caserta&#39; e a abóbora híbrida &#39;Takaiama&#39; apresentaram alta suscetibilidade ao ZLCV. O pepino &#39;Safira&#39; apresentou baixa infecção em campo e intermediária em casa de vegetação. Enquanto que a melancia &#39;Crimson Sweet&#39;, o maxixe do Norte, a abóbora rasteira &#39;Menina Brasileira&#39; e a moranga &#39;Alice&#39; apresentaram valores menores de infecção. A moranga &#39;Exposição&#39; foi altamente resistente, pois não foi infectada nos ensaios em campo e em casa de vegetação. / Zucchini lethal chlorosis virus is a specie of the Genus Tospovirus, transmitted by thrips (Frankliniella zucchini), which infects some species of the family Cucurbitaceae. The occurrence of this Tospovirus has already been reported for several Brazilian states and its incidence in cucurbit crops has increased in the last years in some regions. Considering the importance of this Tospovirus for cucurbit crops, very little is known about the damage caused by this virus and the reaction of the different species of cucurbits to infection. This work aimed: to study the efficiency of the RT-PCR for the fast and specific detection of ZLCV, to evaluate the damage caused by this virus on zucchini squash under field condition and the reaction of seven species/varieties of cucurbits to infection with this Tospovirus. The detection of ZLCV by RT-PCR was studied using a pair of primers designed based on the nucleotide sequence of the SRNA of ZLCV (AF067069). Four other Tospovirus species (TSWV, TCSV, GRSV and CSNV) and other virus that infect cucurbits (mild strain PRSV-W-1, wild strain PRSV-WC, mild strain ZYMV-M, wild strain ZYMV-Atibaia and CMV) were included in this test. The RT-PCR reaction generated a fragment of approximately 350 bp, only amplified from total RNA extracted from plant infected with ZLCV. The sequence of this fragment presented 98.2 % identity with the corresponding nucleotide sequence of the S-RNA of ZLCV deposited in the GenBank. The damage caused by ZLCV on zucchini squash (Cucurbita pepo cv. Caserta) was evaluated under field condition. Zucchini squash plants were weekly monitored for the presence of characteristic symptoms induced by ZLCV and PTA-ELISA for virus indexing. Plants were grouped based on the time the symptoms were first seen. Fruits harvested from each plant within each group were classified on marketable (M) and non-marketable (NM) based on the phenotype. Plants that did not show symptoms by the end of the crop were considered still healthy and their yield was used as control. Zucchini squash plants that showed symptoms of ZLCV infection up to 23 days after emergency (DAE) did not yield any fruit. Marketable fruits were first harvested only from plants that showed symptoms 42 DAE. However, the yield of marketable fruits was reduced by 78.5 %, as compared to that from asymptomatic plants. Plants that showed symptoms 55 DAE showed a reduction on the yield of marketable fruit of 9.6%. The reaction of seven species/varieties of cucurbits to infection with ZLCV was evaluated under field and greenhouse conditions. In the field experiment, ZLCV infection occurred naturally. In the greenhouse, plants were twice mechanically inoculated with ZLCV at the cotyledonal stage. Evaluations were based on symptoms expression and PTA-ELISA. Zucchini squash &#39;Caserta&#39; and hybrid squash &#39;Takaiama&#39; were highly susceptible. The cucumber &#39;Safira&#39; presented low percentage of infected plants in the field and intermediate in the greenhouse. Watermelon &#39;Crimson Sweet&#39;, northern gherkin, long neck squash &#39;Menina Brasileira&#39; and winter squash &#39;Alice&#39; presented lower values of infected plants. Winter squash &#39;Exposição&#39; was highly resistant to infection under field and greenhouse conditions.

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