• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 13
  • 10
  • 5
  • 3
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 39
  • 39
  • 12
  • 11
  • 10
  • 10
  • 5
  • 5
  • 4
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Estudo da microbiota de pacientes portadores de doença de Chagas / Study of the microbiota of patients with Chagas disease

Basqueira, Marcela de Souza 20 August 2018 (has links)
INTRODUÇÃO: A doença de Chagas é causada pelo protozoário flagelado Trypanosoma cruzi (T. cruzi) e ainda hoje representa um grande problema de saúde pública tendo infectado mais de oito milhões de pessoas. A patogênese da cardiomiopatia chagásica ainda não é completamente compreendida. A inflamação no miocárdio é intensa em relação ao número de parasitos presentes e também se observa um dano progressivo em outros órgãos como esôfago e cólon em 30% a 40% dos casos em que se diagnosticou a doença. Alguns estudos começaram a mostrar que a resposta imunológica a um parasita pode depender da microbiota intestinal; porém, ainda não existem estudos com a tecnologia de sequenciamento de nova geração (NGS) que descrevam a microbiota intestinal em doença de Chagas. É possível que uma pequena alteração do peristaltismo intestinal, decorrente da infecção por T. cruzi possa alterar a colonização de algumas bactérias as quais podem causar mudanças na reatividade do sistema imune como aumentar a resposta autoimune, gerando maior dano ao coração. OBJETIVO: Este trabalho objetivou descrever a microbiota intestinal de acordo com a forma clínica da doença de Chagas, através da amplificação do gene 16s RNA ribossomal e avaliar seu papel na patogênese da doença. MÉTODO: Foram selecionados 114 indivíduos, sendo 30 portadores da forma cardíaca da doença, 11 com a forma digestiva (megacólon), 32 com a indeterminada e 31 indivíduos saudáveis (controles). De cada um deles, foram coletadas amostras de fezes para a análise da microbiota por meio de técnicas de sequenciamento de nova geração Ion Torrent. Os resultados obtidos foram analisados pelo software QIIME para determinar a população de bactérias presentes nas amostras. A análise estatística foi realizada utilizando-se os testes não paramétricos de Kruskal-Wallis e Mann-Whitney U-test. RESULTADOS: A frequência relativa do filo Verucomicrobia foi significantemente menor no grupo cardíaco em comparação ao grupo controle e as outras formas clínicas: indeterminada e digestiva. Apesar da abundância relativa desse filo ser menor do que 1%, a diferença observada se manteve significante, mesmo após a correção de Bonferroni. CONCLUSÕES: Nosso estudo sugere que uma menor proporção do filo Verrucomicrobia possa estar relacionada ao processo inflamatório na forma cardíaca; porém, ainda pouco se conhece sobre este grupo de bactérias e seus componentes, que nos permita afirmar o seu efetivo papel na forma cardíaca da doença de Chagas / INTRODUCTION: Chagas disease is caused by the flagellate protozoan Trypanosoma cruzi (T.cruzi) and still represents a major public health problem with more than eight million people infected. Chagas cardiomyopathy pathogenesis is still not completely understood. Inflammation in the myocardium is intense in relation to the number of parasites present and progressive damage is also observed in other organs such as the esophagus and colon in 30% to 40% of the cases. Some studies are beginning to show that the immune response to a parasite may depend on the intestinal microbiota. However, there are no studies using NGS technology that describes the intestinal microbiota of Chagas disease. It is possible that a small change in intestinal peristalsis due to T cruzi infection may alter the colonization of some bacteria. These changes could cause changes in the reactivity of the immune system such as increasing the autoimmune response causing greater damage to the heart. OBJECTIVE: This study aimed to describe the intestinal microbiota according to the clinical form of Chagas disease, through amplification of the 16s ribosomal RNA gene and to evaluate its role in the pathogenesis of the disease. METHODS: A total of 114 individuals were selected, 30 of cardiac form of the disease, 11 with the digestive form (megacolon), 32 with indeterminate form and 31 healthy individuals (controls). Stool samples were collected and analysed for the microbiota using Ion Torrent sequencing technique. The results were analyzed by the QIIME software to determine the population of bacteria present in the samples. Statistical was performed using Kruskal-Wallis non-parametric test and Mann-Whitney U-test. RESULTS: The relative frequency of the Verrucomicrobia phylum was significantly lower among the cardiac group when compared to control, indeterminate and digestive form. Our study suggest that the phylum Verrucomicrobia may play a role in the miocardio inflammation process in Chagas disease, however little is known about these bacteria to infer the mechanism
22

Desenvolvimento e validação experimental de uma metodologia in house para amplificação e sequenciamento do genoma completo do Zika vírus. / Development and validation of an in-house method for whole genome amplification and sequencing of Zika virus.

Pour, Shahab Zaki 19 June 2018 (has links)
O zika é um arbovírus emergente. Há evidências para a relação entre o zika e a microcefalia congênita e também com a síndrome de Guillain-Barre. Várias características do vírus são importantes, como a persistência do vírus no sêmen por vários meses, transmissão sexual e evidência de transmissão pré-natal. As mães grávidas infectadas com zika podem dar à luz crianças aparentemente saudáveis que podem apresentar manifestações e complicações tardias. Existe uma clara necessidade de diagnosticar e sequenciar amostras clínicas do ZIKV que circulam na América do Sul, especificamente no Brasil. No entanto, as baixas cargas virais observadas que são observadas comumente em amostras humanas constituem um fator complicador para detecção, amplificação e sequenciamento. Neste projeto, propor projetar um fluxo de trabalho otimizado para o sequenciamento completo do genoma com base no pré-enriquecimento por PCR (reação em cadeia da polimerase) e pools de amplicons. / Zika is an emerging arbovirus. There is enough evidence for the relation between Zika and congenital microcephaly and also with the Guillain-Barre syndrome. Several characteristics of the virus are important, such as persistence of the virus in semen for several months, sexual transmission and evidence of prenatal transmission. Zika infected pregnant mothers may give birth to apparently healthy children that may show late manifestations and complications. There is a clear necessity of diagnosing and sequencing clinical samples of ZIKV circulating in South America, specifically in Brazil. Nevertheless, the observed low viral loads that are commonly in human samples constitute a complicating factor for detection, amplification and sequencing. In this project, we aim to design an optimized workflow for full genome sequencing based on pre-enrichment by PCR (polymerase chain reaction) and amplicon pools.
23

Análise do transcriptoma (RNAseq) das células foliculares tireoidianas revela uma diversidade de ações autócrinas do T3. / ranscriptoma analysis of thyroid follicular cells reveals a diversity of autocrine actions of T3.

Dias, Rafael Benjamin Araújo 06 December 2018 (has links)
Os hormônios tireoidianos (HTs) desempenham um papel importante em diversos processos, tais como o crescimento, desenvolvimento e metabolismo dos tecidos em geral. Embora estudos tenham demonstrado que os HTs agem diretamente nas células foliculares da tireoide reduzindo sua resposta ao TSH, pouco se sabe, a nível molecular, sobre essa e outras ações dos HTs na própria glândula tireoide. Nesse sentido, o objetivo do presente trabalho foi avaliar alterações no perfil de expressão gênica nas células foliculares tireoidianas (células PCCl3) em reposta ao tratamento com triiodotironina (T3). Após atingir confluência desejada, as células PCCl3 foram mantidas em meio depletado de HTs (grupo Hipo) por 24h. Após esse período, parte das células foi tratada com 10-7M de T3 (grupo T3) por 24 h. As células foram, então, lisadas para extração de RNA total para análise do transcriptoma, por RNAseq. Foi obtido como resultado, uma lista de genes diferencialmente expressos da qual foram selecionados cinco genes para validação in vitro (novo lote de células PCCl3 submetidas às mesmas condições descritas acima) e in vivo [ratos Wistar (250g), tratados por 4 semanas com T3 (1,5 μg/100g de peso corporeo; grupo hipertireoideo) ou PTU (10 μg/100g de peso corporeo; grupo hipotireoideo): o Slc16a1, que codifica o MCT8, responsável pelo transporte de T3 através da membrana, o Snrpd1, 9-March, Pfdn1 e Fam103a1, que codificam proteínas envolvidas no controle pós-transcricional e pós-traducional da expressão gênica. O tratamento com T3 estimulou a expressão dos genes Snrpd1, Pfdn1 e Fam103a1, enquanto reduziu a expressão de 9-March e Slc16a1. Juntos esses resultados demonstram a existência de um efeito autócrino exercido pelo T3 sobre o controle do seu próprio turnover proteico. / Thyroid hormones (HTs) play an important role in many processes, such as growth, development and metabolism of tissues in general. Although studies have shown that HTs act directly on follicular thyroid cells reducing their response to TSH, little is known, at the molecular level, about this and other actions of HTs in the thyroid gland itself. In this sense, the aim of the present study was to evaluate changes in the gene expression profile in the thyroid follicular cells (PCCl3 cells) in response to triiodothyronine (T3) treatment. After reaching 60% confluence, PCCl3 cells were maintained in HT depleted medium (Hypo group) for 24h. After this time, part of the cells was treated with 10-7M T3 (T3 group) for 24 h. Cells were then lysed for total RNA extraction for transcriptome analysis by RNAseq. As a result, a list of differentially expressed genes from which five genes for in vitro validation (PCCl3 cells under the same conditions described above) and in vivo [Wistar rats (250g), treated for 4 weeks with T3 (1.5 &um;g / 100 g body weight, hyperthyroid group) or PTU (10 &um;g / 100 g body weight; hypothyroid group): Slc16a1, which encodes MCT8, responsible for the transport of T3 through the membrane, Snrpd1, 9-March, Pfdn1 and Fam103a1, which encode proteins involved in post-transcriptional and post-translational control of gene expression. T3 treatment stimulated the expression of the Snrpd1, Pfdn1 and Fam103a1 genes, while reducing the expression of 9-March and Slc16a1. Together these results demonstrate the existence of an autocrine effect exerted by T3 on the control of its own protein turnover.
24

Desenvolvimento de metodologias para identificação molecular do HPV

Rocha, Bruno Garcia 31 March 2016 (has links)
Submitted by Livia Mello (liviacmello@yahoo.com.br) on 2016-10-14T19:44:04Z No. of bitstreams: 1 TeseBGR.pdf: 2376550 bytes, checksum: 4ee6a0f02e589ae693965093fa4f2f42 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-11-08T18:48:20Z (GMT) No. of bitstreams: 1 TeseBGR.pdf: 2376550 bytes, checksum: 4ee6a0f02e589ae693965093fa4f2f42 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-11-08T18:48:29Z (GMT) No. of bitstreams: 1 TeseBGR.pdf: 2376550 bytes, checksum: 4ee6a0f02e589ae693965093fa4f2f42 (MD5) / Made available in DSpace on 2016-11-08T18:48:36Z (GMT). No. of bitstreams: 1 TeseBGR.pdf: 2376550 bytes, checksum: 4ee6a0f02e589ae693965093fa4f2f42 (MD5) Previous issue date: 2016-03-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The Human Papiloma Virus (HPV) is a Sexually Transmitted Disease (STD) very common in the world. It infects the human epithelium may persisting of asymptomatic form or causing some neoplasia. Many studies report the association between HPV and many kinds of cancer such as: lap utero, anus, penis, vagina and vulva. According to INCA data for the year of 2016 are expected 16.340 new cases of lap utero cancer, being the second most frequent case in the female population in Brazil. For the recognition of the virus, there`s a lots of tracking methods, as morphological test (pap test), that observes cytopathic effects caused by the virus on human cells, suggesting the existence of infection, however this type of test presents low results and has shown high taxes of false negative and positive results. To overcome this problems, countless studies has shown the effect of molecular techniques utilization to increase the sensibility and especially, getting recognize and genotyping the HPV virus. On this recent studies, were tested distinct molecular techniques for typing the HPV virus, as Conventional PCR followed by Sanger Sequencing , Real time PCR (SYBRGreen® e Taqman ®) and Sequencing of New Generation. Altogether were collected 318 samples pf cervix grated, and from this material were collected the DNA using an adapted protocol (POWELL; GANNON, 2002). Using the conventional PCR technique followed by Sanger Sequencing we obtained 65 positives samples for the HPV(21%), in 49 samples(75,3%) it was possible to identify the HPV type, in the other 16 samples(24,7%) it was not possible the identification, probably because the infection was formed for two or more types of the virus. With the real time PCR technique using SYBRGreen®, were accomplished an experimente with 30 samples, which was possible to confirm the results in 28 of it, using Sanger Sequencing. In two samples the results are not confirmed, being possible to positive the sample, showing high sensibility of the real time PCR technique. The methodology of New Generation Sequencing (NGS) it showed useful for HPV identification, being one of the first studies published for routine use. And it has great prospects because besides HPV can identify other microorganisms in the sample and quantifies them as well. / O Papilomavírus humano conhecido como HPV é uma doença sexualmente transmissível frequente em todo mundo, ele infecta o epitélio de seres humanos, podendo persistir de forma assintomática ou causar neoplasias. Diversos estudos relatam a associação entre o HPV (Alto Risco) e diversos tipos de câncer como: colo de útero, ânus, orofaringe, pênis, vagina e vulva. Segundo dados do INCA para o ano de 2016, são esperados 16.340 novos casos de câncer de colo de útero, sendo de maior frequência na população feminina no Brasil. Para a identificação do vírus existem inúmeros métodos de rastreio como testes morfológicos (exame do Papanicolau), que observam os efeitos citopáticos que o vírus provoca nas células sugerindo a existência da infecção, mas este tipo de teste apresenta baixa especificidade e vem apresentando altas taxas de falsos-negativos e positivos. Para contornar estes problemas inúmeros estudos têm demostrando a eficácia da utilização de técnicas moleculares, para aumentar a sensibilidade e especificidade, conseguindo identificar e genotipar o vírus do HPV. No presente estudo foram testadas diferentes técnicas moleculares para a identificação do vírus do HPV como: PCR convencional seguida por sequenciamento Sanger, PCR em tempo real (SYBRGreen® e Taqman®) e sequenciamento de nova geração. Ao todo foram coletadas 318 de amostras de raspado do colo cervical. Deste material foi extraído o DNA utilizando um protocolo adaptado (POWELL, GANNON, 2002). Utilizando a técnica da PCR convencional seguida por sequenciamento Sanger obtivemos 65 amostras positivas para o HPV (21%), destas 49 amostras (75,3%) foi possível identificar o tipo do HPV e em 16 casos (24,7%) não foi possível identificar o vírus, sendo possivelmente uma infecção formada por dois ou mais tipos do vírus. Com a técnica de PCR em tempo real utilizando SYBRGreen® foi realizado um experimento com 30 amostras sendo possível confirma o resultado destas com o sequenciamento Sanger em 28 casos. Em duas amostras os resultados não corroboraram, sendo possível positivar a amostra. Mostrando a maior sensibilidade da técnica de PCR em tempo real. A metodologia de sequenciamento de nova geração (NGS) se mostrou útil para identificação do HPV, demonstrada neste trabalho de maneira inédita. O uso do NGS apresenta boas perspectivas pois além do HPV pode identificar outros microrganismos na amostra e quantifica-los.
25

Identificação de transcritos diferencialmente expressos por Pasteurella multocida em condição de privação de ferro por sequenciamento de nova geração

Silva, Mayara Inácio Vincenzi da 07 August 2015 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2018-05-02T17:09:56Z No. of bitstreams: 1 DISS_2015_Mayara Inácio Vincenzi da Silva.pdf: 1467868 bytes, checksum: 1589e777267d83f74d5b55da57e6a5db (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-05-16T15:13:07Z (GMT) No. of bitstreams: 1 DISS_2015_Mayara Inácio Vincenzi da Silva.pdf: 1467868 bytes, checksum: 1589e777267d83f74d5b55da57e6a5db (MD5) / Made available in DSpace on 2018-05-16T15:13:07Z (GMT). No. of bitstreams: 1 DISS_2015_Mayara Inácio Vincenzi da Silva.pdf: 1467868 bytes, checksum: 1589e777267d83f74d5b55da57e6a5db (MD5) Previous issue date: 2015-08-07 / CAPES / Ferro (Fe) é um elemento essencial e a capacidade de adquiri-lo in vivo têm sido descrita em diversos agentes patogênicos através de fatores de virulência. Análises globais de transcritos durante a privação de ferro tem sido descritos através da técnica de “microarray”, entretanto através da técnica de RNA-seq recentemente tem demonstrado resultados superiores. O isolado de Pasteurella multocida (Pm 16759) altamente patogênica em suínos foi cultivado em duas condições com diferentes concentrações de Fe (controle e privação) com o objetivo de analisar transcritos diferencialmente expressos. O RNA total das duas condições foi extraído e sequenciado através da plataforma de nova geração Ion Torrent. Os dados foram analisados no Software Ion Reporter™ e processados no programa Rockhopper. Foram obtidas 1.341.615 leituras com tamanho médio de 81pb, com 96% de alinhamento com o genoma de Pasteurella multocida subsp. multocida 3480 e 98,8% de acurácia. No mapeamento das leituras das duas condições, observou-se 2,652 transcritos e destes, 177 (6,7%) foram diferencialmente expressos, sendo 93 na condição controle (Fe+) e 84 na condição de privação (Fe-). Na condição de privação de ferro, o perfil de transcritos foram associados a função de transporte celular (fbpABC, high-affinity Fe2+/Pb2+ permease e periplasmic protein probably involved in hight-affinity Fe2+), reguladores transcricionais e proteínas hipotéticas. O perfil na condição controle (Fe+) apresentou transcritos diferencialmente expressos associados ao RNAs anti-sense (asRNA) e genes do metabolismo energético (fructose-1,6-bisfosfatase). A técnica de RNA-seq mostrou-se eficiente na identificação de transcritos diferencialmente expressos por P. multocida em condições de privação de Fe, o que pode auxiliar nos estudos de patogenicidade. / Iron (Fe) is an essential element and the ability to acquire it, in vivo, have been described in several pathogens such as virulence factors. Global analyses of transcripts during iron deprivation have been described by microarray studies, however, recently RNA-seq analysis shows superior results. The high pathogenic swine strain of Pasteurella multocida (BRMSA 1113) was grown in the two conditions with different concentrations of Fe (control and deprivation) in order to analyze the differentially expressed transcripts. The total RNA of the two conditions was extracted and sequenced by new generation Ion Torrent plataform. Data were analyzed in Ion Reporter ™ Software and processed in Rockhopper software. Sequence analysis shows 1,341,615 readings with median length of 81pb, with 96% of alignment to the reference genome Pasteurella multocida strain 3489, and 98.8% accuracy. Reads mapping to genome of P. multocida in these two conditions, detected 2,652 transcripts, which , 177 (6.7%) were differentially expressed, with 93 in the control condition (Fe +) and 84 provided with iron deprivation condition (Fe-). In condition (Fe-), differential expressed transcript profile were associated to function of cellular transport (fbpABC,, high-affinity Fe2+/Pb2+ permease and periplasmic protein probably involved in hight-affinity Fe2+), transcptional regulators and hypothetical proteins. The control condition (Fe+) shows differential expressed transcripts profile associated to RNA anti-sense (asRNA) energetic metabolism genes (fructose-1,6-bisphosphatase). The technique of RNA-seq proved effective in identifying novel differentially expressed transcripts by P. multocida (BRMSA 1113) under conditions of Fe deprivation, which can assist in pathogenicity studies.
26

Décryptage des réseaux d'interactions plante-champignon pour une meilleure gestion des subéraies méditerranéennes / Deciphring of plant-fungus interactions networks for better Management of Mediterranean cork oak

Maghnia, Fatima-Zahra 19 July 2017 (has links)
Le chêne-liège (Quercus suber) est une essence forestière d’une grande importance écologique et socio-économique pour les habitants de Méditerranée. Cependant, au cours des dernières décennies, ces subéraies et particulièrement les subéraies marocaines ont été soumises à de fortes contraintes climatiques, environnementales et humaines entrainant une accélération des processus de dégradation. La conservation de ces écosystèmes est fortement dépendante de notre capacité à prédire les changements induits par ces différentes pressions ainsi que du développement d’approches durables pour leur réhabilitation. Dans ce contexte, l’identification d’indicateurs biologiques de l’état de santé des subéraies et l'intensification des processus de facilitation entre plantes (arbres/arbustes) apparaissent comme des stratégies écologiques prometteuses. Le succès de ces approches est cependant assujetti à notre compréhension des interactions entre les communautés végétales et les champignons du sol, notamment les champignons mycorhiziens, éléments clés du fonctionnement des écosystèmes forestiers. Ce travail a visé le décryptage des réseaux fongiques, notamment mycorhiziens associés au chêne-liège et la végétation du sous-bois dans trois subéraies marocaines (Maâmora, Benslimane, Chefchaoun) caractérisées par différents niveaux de dégradation. La diversité fongique associée aux racines du chêne-liège et à plusieurs plantes arbustives représentatives des subéraies (Cistus salviifolius, Cistus monpeliensis et Lavandula stoechas) a été étudiée en combinant les méthodes traditionnelles basées sur l’aspect morphologique des mycorhizes et les nouvelles technologies de séquençage haut-débit par identification moléculaire des communautés fongiques.Les résultats obtenus représentent la plus vaste enquête de la diversité fongique du sol, notamment mycorhizienne, au sein des subéraies marocaines. Différents niveaux de structuration des communautés de champignons du sol ont été révélés, fonction de l’habitat, du type de plantes et de l'état de dégradation. Une large gamme d’indicateurs fongiques de l’état de dégradation de la subéraie, en lien avec la plantes hôte, ont pu être mise en évidence au sein des différents habitats, soulignant l’importance de plusieurs champignons ectomycorhiziens (notamment Cenococcum, Russula, Terfezia et Tomentella) mais aussi des champignons mycorhiziens éricoïdes (Cladophialophora, Oidiodendron) et à arbuscules (Rhizophagus, Redeckera, Racocetra, Paraglomus). Ce travail a permis d’établir une base de données majeure sur l’écologie des champignons du sol dans les subéraies marocaines, et de proposer un nouvel éclairage sur leur potentiel pour le suivi de l’état de santé des subéraies, ainsi que pour la mise en place de programmes de conservation adaptés tenant compte aussi des champignons associés. L’application des approches proposées à une plus large diversité d’écosystèmes forestiers devrait constituer un atout important pour la meilleure compréhension du fonctionnement biologique des écosystèmes forestiers et leur sauvegarde face à l’aggravation des pressions humaines et climatiques au niveau mondial. / The Cork oak (Quercus suber) forests play an important role in terms of ecological services and socio-economic development for the Mediterranean populations. However, the cork oak forests, notably in the Southern Mediterranean basin are highly threatened by increasing human and climate pressures, which accelerates desertication. The conservation of this ecosytem is strongly dependent of our ability to predict the environmental changes induced by these pressures as well as to develop sustainable approach for their restoration. In this context, the identification of biological indicators of cork oak health and the intensification of plant-plant facilitation processes appears as promisising ecological strategies. Their success is however subjected to our understanding of plant-fungal interactions, notably with fungal mycorrhiza, key factors of forest ecosystem functionning. The current work aimed at deciphering plant-fungal networks, notably mycorrhizal networks with cork oak and its understory shrub vegetation in three Moroccan cork oak habitats (Maâmora, Benslimane, Chefchaoun) characterized by different degradation levels. The root-fungal diversity associated to cork oak and major components of its understory shrub vegetation (Cistus salviifolius, Cistus monpeliensis et Lavandula stoechas) has been analysed by combining traditional methods based on morphological identification, and new generation high- throughput DNA sequencing methods to characterize communities at the molecular level.The study represents the most extensive survey of soil fungal diversity, notably mycorrhizal diversity, in Moroccan cork oak ecosystems. Different fungal community structures were revealed, depending on habitat, plant host type, and degradation forest status. A wide range of fungal indicators of plant type × forest status has been identified, highlighting the importance of several ectomycorrhizal fungi (notably Cenococcum, Russula, Terfezia and Tomentella) as well as ericoid mycorrhizal fungi (Cladophialophora, Oidiodendron) and arbuscular mycorrhizal fungi (Rhizophagus, Redeckera, Racocetra, and Paraglomus). The current work provides an extensive database on the ecology of soil fungi related to the Moroccan cork oak forest, offers new insights into the potential of soil fungi for monitoring the health of the cork oak forest, and for the developement of efficient conservation programs of this ecosystem by taking into account the soil fungal communties associated. The use of proposed appoaches to a larger diversity of forest ecosystems are promising to better understand the biological fonctionning of forest ecosystem and their conservation in response to the worsening of worldwide human and climate pressures.
27

Estudo da microbiota de pacientes portadores de doença de Chagas / Study of the microbiota of patients with Chagas disease

Marcela de Souza Basqueira 20 August 2018 (has links)
INTRODUÇÃO: A doença de Chagas é causada pelo protozoário flagelado Trypanosoma cruzi (T. cruzi) e ainda hoje representa um grande problema de saúde pública tendo infectado mais de oito milhões de pessoas. A patogênese da cardiomiopatia chagásica ainda não é completamente compreendida. A inflamação no miocárdio é intensa em relação ao número de parasitos presentes e também se observa um dano progressivo em outros órgãos como esôfago e cólon em 30% a 40% dos casos em que se diagnosticou a doença. Alguns estudos começaram a mostrar que a resposta imunológica a um parasita pode depender da microbiota intestinal; porém, ainda não existem estudos com a tecnologia de sequenciamento de nova geração (NGS) que descrevam a microbiota intestinal em doença de Chagas. É possível que uma pequena alteração do peristaltismo intestinal, decorrente da infecção por T. cruzi possa alterar a colonização de algumas bactérias as quais podem causar mudanças na reatividade do sistema imune como aumentar a resposta autoimune, gerando maior dano ao coração. OBJETIVO: Este trabalho objetivou descrever a microbiota intestinal de acordo com a forma clínica da doença de Chagas, através da amplificação do gene 16s RNA ribossomal e avaliar seu papel na patogênese da doença. MÉTODO: Foram selecionados 114 indivíduos, sendo 30 portadores da forma cardíaca da doença, 11 com a forma digestiva (megacólon), 32 com a indeterminada e 31 indivíduos saudáveis (controles). De cada um deles, foram coletadas amostras de fezes para a análise da microbiota por meio de técnicas de sequenciamento de nova geração Ion Torrent. Os resultados obtidos foram analisados pelo software QIIME para determinar a população de bactérias presentes nas amostras. A análise estatística foi realizada utilizando-se os testes não paramétricos de Kruskal-Wallis e Mann-Whitney U-test. RESULTADOS: A frequência relativa do filo Verucomicrobia foi significantemente menor no grupo cardíaco em comparação ao grupo controle e as outras formas clínicas: indeterminada e digestiva. Apesar da abundância relativa desse filo ser menor do que 1%, a diferença observada se manteve significante, mesmo após a correção de Bonferroni. CONCLUSÕES: Nosso estudo sugere que uma menor proporção do filo Verrucomicrobia possa estar relacionada ao processo inflamatório na forma cardíaca; porém, ainda pouco se conhece sobre este grupo de bactérias e seus componentes, que nos permita afirmar o seu efetivo papel na forma cardíaca da doença de Chagas / INTRODUCTION: Chagas disease is caused by the flagellate protozoan Trypanosoma cruzi (T.cruzi) and still represents a major public health problem with more than eight million people infected. Chagas cardiomyopathy pathogenesis is still not completely understood. Inflammation in the myocardium is intense in relation to the number of parasites present and progressive damage is also observed in other organs such as the esophagus and colon in 30% to 40% of the cases. Some studies are beginning to show that the immune response to a parasite may depend on the intestinal microbiota. However, there are no studies using NGS technology that describes the intestinal microbiota of Chagas disease. It is possible that a small change in intestinal peristalsis due to T cruzi infection may alter the colonization of some bacteria. These changes could cause changes in the reactivity of the immune system such as increasing the autoimmune response causing greater damage to the heart. OBJECTIVE: This study aimed to describe the intestinal microbiota according to the clinical form of Chagas disease, through amplification of the 16s ribosomal RNA gene and to evaluate its role in the pathogenesis of the disease. METHODS: A total of 114 individuals were selected, 30 of cardiac form of the disease, 11 with the digestive form (megacolon), 32 with indeterminate form and 31 healthy individuals (controls). Stool samples were collected and analysed for the microbiota using Ion Torrent sequencing technique. The results were analyzed by the QIIME software to determine the population of bacteria present in the samples. Statistical was performed using Kruskal-Wallis non-parametric test and Mann-Whitney U-test. RESULTS: The relative frequency of the Verrucomicrobia phylum was significantly lower among the cardiac group when compared to control, indeterminate and digestive form. Our study suggest that the phylum Verrucomicrobia may play a role in the miocardio inflammation process in Chagas disease, however little is known about these bacteria to infer the mechanism
28

Genome-wide genetic variation in two sister species of cold-resistant leaf beetle: migration and population adaptation.

Kastally, Cheldy 08 January 2018 (has links) (PDF)
An important goal of biology is to understand the key mechanisms of evolution underlying the diversity of living organisms on Earth. In that respect, the recent innovations in the field of new generation sequencing technologies (NGS) are bringing new and exciting opportunities. This thesis presents results obtained with these tools in the specific context of the study of two sister species of cold-adapted leaf beetles, Gonioctena intermedia and G. quinquepunctata. More specifically, this work is focused around four research directions: the two first explore methods of statistical inference using a spatially explicit model of coalescence, by (1) evaluating the potential of various summary statistics to discriminate phylogeographic hypotheses, and (2) investigating the dispersal abilities of a montane leaf beetle, G. quinquepunctata, using an original method that avoids using summary statistics. The third research direction focuses on the adaptation to cold conditions in this montane leaf beetle, by testing the association between genetic polymorphism across tens of thousands of genetic markers and altitude in samples collected at various elevation levels in the Vosges (France). Finally, the fourth, and last, research axis presents the discovery of mitochondrial heteroplasmy, i.e. the presence in an individual of multiple copies of the mitochondrial genome, in natural populations of G. intermedia. We illustrate, here, how NGS technologies could help identify this phenomenon, probably underestimated in animals, on a large scale. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
29

Rysk krigföring : new-Generation Warfare, Full-Spectrum Conflict eller något annat?

Ihs, Robert January 2019 (has links)
Russians actions in Ukraine came as a chock to the west, who have been striving to conceptualize Russian warfare since. This has resulted in several conflicting definitions involving different means and methods. This might be problematic, both for a country and its military, in trying to define and counter the threat of Russian warfare. It might also be problematic for scientific enquiry, since the definitions might become too broad and neglect vital aspects of Russian warfare. This study there-fore compare and test two rivalling theories about Russian warfare, New-Generation Warfare (NGW) and Full-Spectrum Conflict (FSC), by analysing Russia’s actions in the Ukrainian conflict. By doing so it aims to shed light on which of the two theories offers the best approach to analysing the case. The study uses a qualitative text research method to examine secondary sources describing the conflict and transliterations of Putin’s speeches. Several indicators for each theoretical framework are confirmed and made the analysis possible. The results of this analysis show that Russia in Ukraine used their means and methods synchronously rather than applying a diachronic course of action as advocated by NGW. Results therefore suggest that FSC and its mix of means and methods better describes Russia’s actions in Ukraine.
30

Modernizace ruské armády v letech 2008-2014: důsledky pro bezpečnost v postsovětském prostoru / Modernization of Russian army 2008-2014: consequences for post-Soviet area security.

Buchar, Jan January 2015 (has links)
Until 2008, almost two decades since the end of the cold war, Russia still retained old Soviet military structures. Steady opposition by the Russian generals against military modernization and reforms was finally broken in relation with the poor performance of Russian forces during the Russia-Georgian war in 2008. The process of modernization commenced in the following years has important security implications for post-Soviet countries. We could observe the new abilities of the Russian military during the seizure of the Crimean peninsula in 2014. Russian forces had been considered an ineffective institution with outdated military technology where corrupt practices were the rule rather than the exception. As we could see in 2008 Georgia Russian forces depended on numerical superiority and blunt military force. On the other hand during the Crimean events of 2014 the Russian military conducted the whole operation with high level of professionalism, without any bloodshed, and with modern weaponry. This research is based on the theory of neorealism which defines key parameters for performing a military modernization analysis. These include numbers, effectivity and strategy of military forces that help us to determine the current strength and power of each state. Therefore this research focuses on the...

Page generated in 0.028 seconds