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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.
171

Molekularbiologische Analyse mikrobieller Gemeinschaften in Talsperrensedimenten

Bleul, Catrin 13 September 2004 (has links)
Mikrobielle Prozesse spielen eine wichtige Rolle im Sediment von Talsperren und Seen. Demgegenüber stehen nur unzureichende Erkenntnisse über die Zusammensetzung mikrobieller Biozönosen in Sedimenten sowie deren Aktivität zur Verfügung. Das Ziel dieser Studie war die Untersuchung und der Vergleich der Zusammensetzung und der Struktur mikrobieller Gemeinschaften in Sedimenten um eine Abschätzung der mikrobiellen Diversität in Talsperrensedimenten unterschiedlicher Trophie zu erreichen. Durch die Kombination der in dieser Arbeit verwendeten Methoden (Vergleichende 16S rDNA Analyse, Fingerprinttechniken, klassische Methoden) konnte eine Charakterisierung der mikrobiellen Zusammensetzung der obersten 5 cm von den Talsperrensedimenten Neunzehnhain, Muldenberg, Quitzdorf und Saidenbach erzielt werden. Die vergleichende 16S rDNA Analyse offenbarte in 2541 analysierten rekombinanten Klonen 528 verschiedene Sequenztypen, welche zu 293 OTUs zusammengefaßt werden konnten. Obwohl die Gemeinschaften der verschiedenen Talsperren nur schwach auf der Ebene der phylogenetischen Gruppen differierten, konnte durch die Verwendung von Ähnlichkeitsindices gezeigt werden, dass jede Talsperre eine spezifische mikrobielle Sedimentgemeinschaft aufweist. Über 60% aller Klone zeigten Ähnlichkeiten von mehr als 97% zu 16S rDNA-Sequenzen kultivierter Organismen oder phylogenetisch eingeordneten Sequenzen (14 bekannte phylogenetische Gruppen). Alle anderen Klone zeigten hohe Sequenzhomologien zu unidentifizierten, phylogenetisch bisher nicht eingeordneten Bakterien. Diese Bakterien waren mit Anteilen zwischen 19,8% (Muldenberg) und 54,6% (Saidenbach) in den 16S rDNA Bibliotheken repräsentiert. Mittels Fingerprinttechniken (DGGE, T-RFLP, ARISA) konnten komplexe Muster der mikrobiellen Diversität erzeugt werden. Dabei konnten die Ergebnisse der 16S rDNA Analyse bestätigt werden. Durch die verwendeten Methoden konnte eine komplexe mikrobielle Diversität in den Sedimenten aufgedeckt werden und die Ergebnisse weisen darauf hin, dass die mikrobielle Diversität in Sedimenten wesentlich höher ist als bisher angenommen.
172

The effects of saltwater intrusion on methanogen community abundance, structure, and activity

Gillespie, Jaimie 25 July 2013 (has links)
Tidal freshwater wetlands (TFW) are at significant risk of loss or alteration due to global climate change, and saltwater intrusion from sea level rise is of particular concern for these habitats due to their proximity to coastal areas. A space-for-time model was used to investigate the effects of saltwater intrusion on soil methanogen communities along naturally occurring salinity gradients on the Waccamaw, James, and Hudson Rivers. Amplification of the methyl coenzyme-M reductase (mcrA) functional gene was used in qPCR, reverse transcription qPCR, and T-RFLP to measure the abundance, activity, and community composition of soil methanogens. Both the abundance and activity of methanogens decreased with increasing salinity, and the both total and active methanogen community composition shifted in response to changes in salinity. This research demonstrates that saltwater intrusion will alter carbon cycling in TFWs, potentially altering their ability to sequester carbon and keep pace with rising sea level.
173

Ocorrência e persistência de fragmentos de transgenia (milho Bt evento MON810) em solos agrícolas brasileiros e avaliação de sua comunidade microbiana / Occurrence and persistence of transgenic fragments of Bt maize (event MO810) in agricultural soils Brazilian and evaluation of its microbial community

Ferrari, Beatriz Maria 12 February 2015 (has links)
O uso de culturas GM (geneticamente modificadas) tem sido questionado quanto ao destino dos produtos derivados da transgenia no ambiente. Com a liberação de exsudatos das raízes das plantas e a decomposição dos resíduos culturais, aumenta-se a quantidade de DNA transgênico no ambiente, que pode ser adsorvido à superfície ativa das partículas do solo e/ou degradado pela ação de enzimas microbianas. A comunidade microbiana do solo pode entrar em contato direto com estes produtos, aumentando a probabilidade de transferência horizontal de fragmentos de DNA transgênico para os microrganismos. Também, alterações na composição dos exsudatos das plantas GM e mudanças em função das práticas de manejo, podem resultar em alterações na composição funcional e estrutural da comunidade microbiana. Assim, faz-se necessário avaliar a persistência dos produtos derivados da transgenia no solo e seus possíveis efeitos sobre a comunidade microbiana. Os objetivos deste estudo foram: avaliar a persistência dos fragmentos 35S-hsp70, hsp70-cry1Ab e cry1Ab-planta da construção gênica do milho Bt (evento MON810) em diferentes tipos de solo e temperaturas, em condições de microcosmo e de campo; e determinar a abundância do número de cópias dos gene 16S rRNA de Bacteria, Firmicutes, Verrucomicrobria e Archaea, e 18S rRNA de Fungo nas mesmas condições, e avaliar a estrutura da comunidade bacteriana em áreas agrícolas de cultivo de milho Bt. No primeiro estudo, o DNA do milho Bt MON810 foi adicionado em solos arenoso e argiloso. Como controle negativo, apenas água estéril foi misturada ao solo. Amostras de solo foram incubadas a 15 e 25ºC. Em campo, os solos foram amostrados em três áreas agrícolas em Fátima do Sul, MS, em dois anos consecutivos. Após extração de DNA, os fragmentos foram quantificados por qPCR. No segundo estudo, foram determinadas a abundância dos genes 16S rRNA de Bacteria, Firmicutes, Verrucomicrobria e Archaea e 18S rRNA de Fungo e avaliada a estrutura da comunidade bacteriana por T-RLFP. Os resultados mostraram que em condições de microcosmo, os fragmentos hsp70-cry1Ab e cry1Ab-planta persistiram até 291 dias, e o fragmento 35S-hsp70 até 180 dias. A temperatura e o tipo de solo não afetaram a persistência dos fragmentos. Em campo, o número de cópias desses fragmentos foi maior na segunda coleta. No segundo estudo, o número de cópias do gene 16S rRNA de Bacteria aumentou com adição de DNA do milho Bt nos microcosmos, e uma redução do número de cópias foi verificada para Archaea, Verrucomicrobia e Fungo. Para Firmicutes, os resultados não foram consistentes. As temperaturas não resultaram em efeito na abundância dos genes, enquanto o tipo de solo teve efeito apenas para Archaea e Verrucomicrobia. Áreas agrícolas com cinco anos de cultivo de milho Bt apresentaram variações na estrutura da comunidade bacteriana em nível de filo, e maior abundância de Fungos no segundo ano de amostragem, enquanto em área com um ano de cultivo, observouse uma redução da população de Firmicutes e Verrucomicrobia. Os maiores efeitos na comunidade microbiana foram verificados entre os anos de amostragem / The use of GM (genetically modified) crops has been questioned about the fate of transgenes is derived products on the environment. With the release of exudates from roots of GM plants and the decomposition of its residues, the amount of transgenic DNA in the environment increases, which can be adsorbed to the active surface of soil particles and/or be degraded by the action of microbial enzymes. Soil microbial communities can come into direct contact with these products, raising the probability of horizontal transfer of transgenic DNA fragments to soil microorganisms. Moreover, changes in exudates composition of GM plants and changes depending on the management practices may result in structural and functional alterations in the microbial community. Thus, it is necessary to evaluate the persistence of transgenes is derivatives in the soil and effects on microbial community. The objectives of this study were to assess the persistence of fragments 35S-hsp70, hsp70-cry1Ab and cry1Abplant from the genetic construct of Bt corn (event MON810) in different soil types and temperatures, in microcosm and field conditions; and to determine the abundance of 16S rRNA copy number of Bacteria, Firmicutes, Verrucomicrobria and Archaea and 18S rRNA of Fungi under the same conditions, and to evaluate the structure of bacterial communities in agricultural areas of Bt corn cultivation. In the first study, DNA from Bt corn MON810 was added to sandy and clay soils. As negative control, only sterile water was mixed with soil. Soil samples were incubated at 15 and 25°C. At the field, soils were sampled in three agricultural areas in Fátima do Sul, MS, in two consecutive years. After DNA extraction, fragments were quantified by qPCR. In the second study, the abundance of 16S rRNA of Bacteria, Firmicutes, Verrucomicrobria and Archaea and 18S rRNA of Fungi were determined and the structure of bacterial communities was evaluated by T-RFLP. The results showed that in microcosm conditions, hsp70-cry1Ab and cry1Ab-plants fragments persisted until 291 days and the 35S-hsp70 up to 180 days. The temperature and the type of soil did not affect the persistence of fragments. In field, the copy number of these fragments was greater in the second sampling. In the second study, the copy number of 16S rRNA of Bacteria increased with the addition of DNA from Bt corn in microcosm, and a reduction in copy number was observed for Archaea, Verrucomicrobia and Fungi. The results were not consistent for Firmicutes. Temperatures resulted in no effect in gene abundance, while the soil was effective only for Archaea and Verrucomicrobia. Agricultural areas with five years of Bt corn cultivation showed variations in bacterial community structure at the phylum level, and greater abundance of fungi in the second year of sampling, while in the area with a year of cultivation, a reduction in population of Firmicutes and Verrucomicrobia was observed. The largest effects on the microbial community were observed between the sampled years
174

Comorbidade leishmaniose visceral/AIDS no Estado de São Paulo, Brasil (1999-2010): aspectos epidemiológicos e moleculares / Comorbidity visceral leishmaniasis/AIDS in São Paulo State, Brazil (1999-2010): epidemiological and molecular aspects

Igor Thiago Borges de Queiroz e Silva 30 October 2013 (has links)
INTRODUÇAO: A leishmaniose atinge milhões de indivíduos mundialmente, relacionada a mudanças ambientais, urbanização, migração e susceptibilidade do hospedeiro. O aumento de casos de leishmaniose visceral (LV) em áreas urbanas pode ser explicado, não só pela adaptação do vetor a diferentes situações ambientais, circulação do parasito e introdução de hospedeiro infectado, como também pela intersecção com áreas de transmissão do HIV. No Brasil, a distribuição dos coinfectados acompanha os grupos de risco para HIV/AIDS (adultos, sexo masculino). A coinfecção LV-HIV/AIDS é registrada com grande frequência no Estado de São Paulo, onde há aumento da prevalência desta coinfecção, assim como da recidiva e da letalidade por LV. Fatores contribuintes para esta elevação, como possíveis determinantes da gravidade da LV em pacientes HIV/AIDS, não estão claros, sejam relacionados ao hospedeiro ou ao parasito. OBJETIVOS: Avaliar o comportamento clínico, epidemiológico, terapêutico e imunológico e a variação genotípica do parasito na coinfecção LV-HIV/AIDS, comparando com pacientes HIV-negativos, em pacientes do Estado de São Paulo. MATERIAIS E MÉTODOS: Coorte retrospectiva, utilizando dados secundários de programas de rotina epidemiológica da Secretaria de Estado da Saúde de São Paulo e do Ministério da Saúde do Brasil, entre 1999-2010. Análise molecular por PCR-RFLP do kDNA de Leishmania (L.) infantum de aspirado de medula óssea para desenvolvimento de uma árvore fenética, comparando os indivíduos entre si quanto ao desfecho, sexo, idade e infecção pelo HIV. RESULTADOS: 1614 casos de LV e 117 (7,25%) de coinfectados LV-HIV/AIDS, com predomínio destes no sexo masculino, entre os 31-50 anos de idade. Tríade febre e hepatoesplenomegalia foi mais frequente no grupo HIV-negativo. Maior letalidade por LV (24,2 x 8,2 - p =0,000) e recidiva (10,5 x 1,8 - p = 0,000) nos pacientes HIV-positivos comparando aos HIVnegativos. Entre os coinfectados, observou-se maior taxa de cura quando a LV foi tratada com Antimonial Pentavalente (69,44%) e Anfotericina B lipossomal (63,82%), p=0,223. Maiores falhas (16,66%, p = 0,034) e letalidade (41,66%, p = 0,192) quando tratado com Anfotericina B deoxicolato. Maiores recidivas (14,89% - p = 0,076) e nenhuma falha com Anfotericina B lipossomal. Houve maior mediana de linfócitos T CD4+ (135) e T CD8+ (550) no grupo de cura dos pacientes LV-HIV/AIDS e houve 50% de recidivas em uso de terapia antirretroviral. A distribuição dos genótipos de Leishmania (L.) infantum não apresentou relação com nenhum dos desfechos avaliados. CONCLUSÕES: Os resultados obtidos revelam pela primeira vez a magnitude da comorbidade LV-HIV/AIDS no Estado de São Paulo, com repercussão direta na recidiva e na letalidade da LV. Há aumento do número de casos de LV e LV-HIV/AIDS nessa região, com maior prevalência de coinfectados em adultos do sexo masculino. Maior letalidade e recidiva nos HIV-positivos e com pior desfecho quando tratado com Anfotericina B deoxicolato. Recidiva elevada quando tratado com Anfotericina B lipossomal, embora sem falhas. Pouca proteção da terapia antirretroviral na proteção das recidivas. Muitos dados incompletos quanto à infecção pelo HIV. PCR-RFLP não discrimina casos HIV-positivos dos HIV-negativos, nem mostra relação direta das recidivas e óbitos com um genótipo específico do parasita, podendo a evolução do paciente estar relacionada diretamente com a resposta do hospedeiro / INTRODUCTION: Leishmaniasis affects millions of individuals worldwide, related to environmental changes, urbanization, migration, and host susceptibility. The increase in cases of visceral leishmaniasis (VL) in urban areas can be explained not only by the vector adaptation to different environmental situations, movement of the parasite and introduction infected host, as well as the intersection with areas of HIV transmission. In Brazil, the distribution of coinfected is accompanying risk groups for HIV/AIDS (adult male). Coinfection VL-HIV/AIDS is recorded with great frequency in São Paulo State, where there is an increased prevalence of co-infection, as well as relapse and lethality by VL. Factors contributing to this increase, as possible determinants of severity of VL in HIV/AIDS patients are not clear, either related to the host or the parasite. OBJECTIVES: To evaluate the clinical, epidemiological, therapeutic and immunological aspects of coinfection VL-HIV/AIDS and genotypic variation in the parasite, compared with HIV-negative patients in the State of São Paulo. MATERIALS AND METHODS: Retrospective cohort study using secondary data from epidemiological routine programs of the State Department of Health of São Paulo and the Ministry of Health of Brazil, between 1999 to 2010. Molecular analysis by PCRRFLP kDNA of Leishmania (L.) infantum from bone marrow aspirate to develop a phenetic tree, comparing individuals with each other about the outcome, gender, age and HIV infection. RESULTS: 1614 cases of VL and 117 (7.25%) of coinfected VLHIV/ AIDS, predominantly those in males, between 31-50 years old. Triad of fever and hepatosplenomegaly was more frequent among HIV-negative. Increased mortality by VL (24.2 x 8.2 - p =0,000) and recurrence (10.5 x 1.8 - p = 0,000) in HIV-positive patients compared to HIV-negative. Among coinfected, there was a higher cure rate when the VL was treated with pentavalent antimony (69.44%) and liposomal amphotericin B (63.82%), p = 0.223. Major failures (16.66%, p = 0.034) and mortality (41.66%, p = 0.192) when treated with amphotericin B deoxycholate. Major recurrences (14.89% - p = 0.076) and no failure with amphotericin B liposome. There were a higher median TCD4+ (135) and TCD8+ (550) lymphocytes in the group of cures and relapse was 50% in those using antiretroviral therapy. The genotype distribution of Leishmania (L.) infantum was not associated with any of the outcomes assessed. CONCLUSIONS: These results show for the first time the magnitude of comorbidity VL-HIV/AIDS in São Paulo State, with direct impact on recurrence and mortality of VL. There are increasing numbers of cases of VL and VL-HIV/AIDS in this region, with the highest prevalence of coinfection in adult males. There is an increased mortality and recurrence in HIV-positive and with worse outcome when treated with amphotericin B deoxycholate. High relapse when treated with liposomal amphotericin B, although flawless. There is little protection of antiretroviral therapy in relapses. There are many incomplete data regarding HIV infection. PCR-RFLP does not discriminate HIVpositive cases from HIV-negative ones or showed direct nexus from recurrences and deaths with a specific genotype of the parasite, but instead could be directly related to the host response
175

Polimorfismo no Gene que Codifica a ?-lactoglobulina e associa??o com caracter?sticas de produ??o em caprinos leiteiros / Polymorphism in the gene encoding the ?-lactoglobulin and Association with Traditional Production in Dairy Goats

Rego, Ramon de Sousa 26 August 2014 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-10-18T11:49:54Z No. of bitstreams: 1 2014 - Ramon de Sousa Rego.pdf: 1491511 bytes, checksum: 746021e21f53b13713de3e8e94d03121 (MD5) / Made available in DSpace on 2016-10-18T11:49:54Z (GMT). No. of bitstreams: 1 2014 - Ramon de Sousa Rego.pdf: 1491511 bytes, checksum: 746021e21f53b13713de3e8e94d03121 (MD5) Previous issue date: 2014-08-26 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The protein quality of milk of goats and digestibility of the lipid fraction are important factors that stand out when compared to milk from cows. The ?-lactoglobulin is the higher abundant protein in whey ruminants being produced in the mammary gland during lactation. It may represent up to 12% of the total protein. We seek to present work was to evaluate the gene ?-Lactoglobulin (BLG) with their genetic polymorphisms in the promoter regions 5 'and 3' UTR and associate them the characteristics of milk production in experimental goat herd. For this 150 goats (Capra hircus) of Saanen and Alpine, genotyped for polymorphisms of the BLG gene were used. For genotyping 10 mL of blood per animal were collected. The blood was used for DNA extraction and amplification of two fragments of the BLG gene by means of polymerase chain reaction (PCR). The amplified fragments were submitted to electrophoresis on polyacrylamide gel and evaluated by by restriction fragment length polymorphism (PCR-RFLP). The SmaI and SacII enzymes were used for the promoter (promoter + exon 1 region) region and the region of exon 7 (exon 7 + region 3 '), respectively. The differences in cutting patterns were visualized on a polyacrylamide gel. In the promoter region of the single nucleotide polymorphism (SNP) at position -60 (C/T) was identified and was associated with the percentage of protein in milk. This result suggests a relationship between genotypes of the promoter region of the BLG gene and the protein level of the milk. The presence of two polymorphisms +4641 (I2/I3) and +4601 (A/G) was observed in the region of exon 7. The I2-I3 variation is characterized by a repeat sequence of 10 bp, varying in two and three times, and it being possible to identify by electrophoresis. The I3 variation was often very low, and there was no association between this polymorphism and any production trait. Polymorphism +4601 (G/A) was identified by enzyme SacII digestion. Alleles were identified frequencies close to those reported by other authors and were associated with the percentage of fat in milk goats, and the animals with the S1S2 genotype had higher fat percentage than S1S1 animals and S2S2. The increased production of lipid content may be related to the characteristic of transporting fatty acids ?-lactoglob / A qualidade proteica do leite de cabras e a digestibilidade da fra??o lip?dica s?o importantes fatores que o destacam, quando comparado ao leite de vacas. A ?-Lactoglobulina ? a prote?na de maior abundancia no soro do leite em ruminantes sendo produzida na gl?ndula mam?ria durante o per?odo de lacta??o. Ela pode representar at? 12% do total proteico. Buscamos com o presente trabalho, avaliar o gene da ?-Lactoglobulina (BLG) com seus polimorfismos gen?ticos nas regi?es promotoras 5? e 3? UTR e associ?-los as caracter?sticas de produ??o de leite no rebanho caprino experimental. Para isso foram utilizadas 150 cabras (Capra hircus) das ra?as Saanen e Alpinas, genotipadas para os polimorfismos do gene BLG. Para a genotipagem foram coletados 10 mL de sangue por animal. O sangue foi utilizado para a extra??o de DNA e amplifica??o de 2 fragmentos do gene BLG por interm?dio da rea??o em cadeia da polimerase (PCR). Os fragmentos amplificados foram ent?o submetidos ? eletroforese em gel de poliacrilamida e avaliados pelo polimorfismo no tamanho do fragmento por restri??o (PCR-RFLP). Foram utilizadas as enzimas SmaI e SacII, para a regi?o promotora (regi?o promotora + ?xon 1) e para a regi?o do ?xon 7 (?xon 7 + regi?o 3?), respectivamente. As diferen?as nos padr?es de corte foram visualizadas em gel de poliacrilamida. Na regi?o promotora o polimorfismo de base ?nica (SNP) na posi??o -60 (C/T) foi identificado e apresentou associa??o com a percentagem de prote?nas no leite. Esse resultado sugere uma rela??o entre os gen?tipos da regi?o promotora do gene BLG e o n?vel proteico do leite. Foi observado na regi?o do ?xon 7 a presen?a de dois polimorfismos +4641 (I2/I3) e +4601 (A/G). A varia??o I2-I3 ? caracterizada pela repeti??o de uma sequ?ncia de 10 pb, variando em duas e tr?s vezes, e sendo poss?vel identifica-la por eletroforese. A varia??o I3 teve frequ?ncia muito baixa, e n?o houve associa??o entre esse polimorfismo e nenhuma caracter?stica de produ??o. O polimorfismo +4601 (A/G) foi identificado por meio da digest?o da enzima SacII. Os alelos identificados tiveram frequ?ncias pr?ximas ?s relatadas por outros autores e apresentaram associa??o com a percentagem de gordura no leite cabras, sendo que os animais com o gen?tipo S1S2 apresentaram maior percentagem de gordura que animais S1S1 e S2S2. A maior produ??o de conte?do lip?dico pode estar relacionada com a caracter?stica de transporte de ?cidos graxos da ?-Lactoglobulina
176

Comorbidade leishmaniose visceral/AIDS no Estado de São Paulo, Brasil (1999-2010): aspectos epidemiológicos e moleculares / Comorbidity visceral leishmaniasis/AIDS in São Paulo State, Brazil (1999-2010): epidemiological and molecular aspects

Silva, Igor Thiago Borges de Queiroz e 30 October 2013 (has links)
INTRODUÇAO: A leishmaniose atinge milhões de indivíduos mundialmente, relacionada a mudanças ambientais, urbanização, migração e susceptibilidade do hospedeiro. O aumento de casos de leishmaniose visceral (LV) em áreas urbanas pode ser explicado, não só pela adaptação do vetor a diferentes situações ambientais, circulação do parasito e introdução de hospedeiro infectado, como também pela intersecção com áreas de transmissão do HIV. No Brasil, a distribuição dos coinfectados acompanha os grupos de risco para HIV/AIDS (adultos, sexo masculino). A coinfecção LV-HIV/AIDS é registrada com grande frequência no Estado de São Paulo, onde há aumento da prevalência desta coinfecção, assim como da recidiva e da letalidade por LV. Fatores contribuintes para esta elevação, como possíveis determinantes da gravidade da LV em pacientes HIV/AIDS, não estão claros, sejam relacionados ao hospedeiro ou ao parasito. OBJETIVOS: Avaliar o comportamento clínico, epidemiológico, terapêutico e imunológico e a variação genotípica do parasito na coinfecção LV-HIV/AIDS, comparando com pacientes HIV-negativos, em pacientes do Estado de São Paulo. MATERIAIS E MÉTODOS: Coorte retrospectiva, utilizando dados secundários de programas de rotina epidemiológica da Secretaria de Estado da Saúde de São Paulo e do Ministério da Saúde do Brasil, entre 1999-2010. Análise molecular por PCR-RFLP do kDNA de Leishmania (L.) infantum de aspirado de medula óssea para desenvolvimento de uma árvore fenética, comparando os indivíduos entre si quanto ao desfecho, sexo, idade e infecção pelo HIV. RESULTADOS: 1614 casos de LV e 117 (7,25%) de coinfectados LV-HIV/AIDS, com predomínio destes no sexo masculino, entre os 31-50 anos de idade. Tríade febre e hepatoesplenomegalia foi mais frequente no grupo HIV-negativo. Maior letalidade por LV (24,2 x 8,2 - p =0,000) e recidiva (10,5 x 1,8 - p = 0,000) nos pacientes HIV-positivos comparando aos HIVnegativos. Entre os coinfectados, observou-se maior taxa de cura quando a LV foi tratada com Antimonial Pentavalente (69,44%) e Anfotericina B lipossomal (63,82%), p=0,223. Maiores falhas (16,66%, p = 0,034) e letalidade (41,66%, p = 0,192) quando tratado com Anfotericina B deoxicolato. Maiores recidivas (14,89% - p = 0,076) e nenhuma falha com Anfotericina B lipossomal. Houve maior mediana de linfócitos T CD4+ (135) e T CD8+ (550) no grupo de cura dos pacientes LV-HIV/AIDS e houve 50% de recidivas em uso de terapia antirretroviral. A distribuição dos genótipos de Leishmania (L.) infantum não apresentou relação com nenhum dos desfechos avaliados. CONCLUSÕES: Os resultados obtidos revelam pela primeira vez a magnitude da comorbidade LV-HIV/AIDS no Estado de São Paulo, com repercussão direta na recidiva e na letalidade da LV. Há aumento do número de casos de LV e LV-HIV/AIDS nessa região, com maior prevalência de coinfectados em adultos do sexo masculino. Maior letalidade e recidiva nos HIV-positivos e com pior desfecho quando tratado com Anfotericina B deoxicolato. Recidiva elevada quando tratado com Anfotericina B lipossomal, embora sem falhas. Pouca proteção da terapia antirretroviral na proteção das recidivas. Muitos dados incompletos quanto à infecção pelo HIV. PCR-RFLP não discrimina casos HIV-positivos dos HIV-negativos, nem mostra relação direta das recidivas e óbitos com um genótipo específico do parasita, podendo a evolução do paciente estar relacionada diretamente com a resposta do hospedeiro / INTRODUCTION: Leishmaniasis affects millions of individuals worldwide, related to environmental changes, urbanization, migration, and host susceptibility. The increase in cases of visceral leishmaniasis (VL) in urban areas can be explained not only by the vector adaptation to different environmental situations, movement of the parasite and introduction infected host, as well as the intersection with areas of HIV transmission. In Brazil, the distribution of coinfected is accompanying risk groups for HIV/AIDS (adult male). Coinfection VL-HIV/AIDS is recorded with great frequency in São Paulo State, where there is an increased prevalence of co-infection, as well as relapse and lethality by VL. Factors contributing to this increase, as possible determinants of severity of VL in HIV/AIDS patients are not clear, either related to the host or the parasite. OBJECTIVES: To evaluate the clinical, epidemiological, therapeutic and immunological aspects of coinfection VL-HIV/AIDS and genotypic variation in the parasite, compared with HIV-negative patients in the State of São Paulo. MATERIALS AND METHODS: Retrospective cohort study using secondary data from epidemiological routine programs of the State Department of Health of São Paulo and the Ministry of Health of Brazil, between 1999 to 2010. Molecular analysis by PCRRFLP kDNA of Leishmania (L.) infantum from bone marrow aspirate to develop a phenetic tree, comparing individuals with each other about the outcome, gender, age and HIV infection. RESULTS: 1614 cases of VL and 117 (7.25%) of coinfected VLHIV/ AIDS, predominantly those in males, between 31-50 years old. Triad of fever and hepatosplenomegaly was more frequent among HIV-negative. Increased mortality by VL (24.2 x 8.2 - p =0,000) and recurrence (10.5 x 1.8 - p = 0,000) in HIV-positive patients compared to HIV-negative. Among coinfected, there was a higher cure rate when the VL was treated with pentavalent antimony (69.44%) and liposomal amphotericin B (63.82%), p = 0.223. Major failures (16.66%, p = 0.034) and mortality (41.66%, p = 0.192) when treated with amphotericin B deoxycholate. Major recurrences (14.89% - p = 0.076) and no failure with amphotericin B liposome. There were a higher median TCD4+ (135) and TCD8+ (550) lymphocytes in the group of cures and relapse was 50% in those using antiretroviral therapy. The genotype distribution of Leishmania (L.) infantum was not associated with any of the outcomes assessed. CONCLUSIONS: These results show for the first time the magnitude of comorbidity VL-HIV/AIDS in São Paulo State, with direct impact on recurrence and mortality of VL. There are increasing numbers of cases of VL and VL-HIV/AIDS in this region, with the highest prevalence of coinfection in adult males. There is an increased mortality and recurrence in HIV-positive and with worse outcome when treated with amphotericin B deoxycholate. High relapse when treated with liposomal amphotericin B, although flawless. There is little protection of antiretroviral therapy in relapses. There are many incomplete data regarding HIV infection. PCR-RFLP does not discriminate HIVpositive cases from HIV-negative ones or showed direct nexus from recurrences and deaths with a specific genotype of the parasite, but instead could be directly related to the host response
177

A model system using insects to vector Fusarium tumidum for biological control of gorse (Ulex europaeus)

Yamoah, Emmanuel January 2007 (has links)
The overall objective of this study was to test the hypothesis that insects can vector F. tumidum conidia to infect gorse plants with the aim of developing an alternative approach to mycoherbicide delivery to control weeds. Four potential insect species (Apion ulicis, Cydia ulicetana, Epiphyas postvittana and Sericothrips staphylinus) were assessed for their ability to vector F. tumidum conidia. To achieve this, the external microflora (bacteria and fungi) and the size and location of fungal spores on the cuticle of these insect species were determined. In addition, the ability of the insects to pick up and deposit F. tumidum conidia on agar was studied. Based on the results from these experiments, E. postvittana was selected for more detailed experiments to determine transmission of F. tumidum to infect potted gorse plants. The factors promoting pathogenicity of F. tumidum against gorse and the pathogen loading required to infect and kill the weed were also determined. The external microflora of the four insect species were recovered by washing and plating techniques and identified by morphology and polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and sequencing of internally transcribed spacer (ITS) and 16S rDNA. A culture-independent technique (direct PCR) was also used to assess fungal diversity by direct amplification of ITS sequences from the washings of the insects. All insect species carried Alternaria, Cladosporium, Nectria, Penicillium, Phoma, Pseudozyma spp. and entomopathogens. Ninety four per cent of the 178 cloned amplicons had ITS sequences similarity to Nectria mauritiicola. E. postvittana carried the largest fungal spores (mean surface area of 125.9 ìm2) and the most fungal CFU/insect. About 70% of the fungi isolated from the insects were also present on the host plant (gorse) and the understorey grass. The mean size of fungal spores recovered from the insect species correlated strongly with their body length (R² = 85%). Methylobacterium aquaticum and Pseudomonas lutea were common on all four insect species. Pseudomonas fluorescens was the most abundant bacterial species. In the pathogenicity trials, the effectiveness of F. tumidum in reducing root and shoot biomass of 16 and 8 wk old gorse plants was significantly increased with wounding of the plants. Older plants (32 wk old) which were wounded and inoculated were significantly shorter, more infected and developed more tip dieback (80%) than plants which were not wounded (32%). This indicates that damage caused by phytophagous insect species present on gorse through feeding and oviposition may enhance infection by F. tumidum. Wounding may release nutrients (e.g. Mg and Zn) essential for conidia germination and germ tube elongation and also provide easier access for germ tube penetration. Conidial germination and germ tube length were increased by 50 and 877%, respectively when incubated in 0.2% of gorse extract solution for 24 h compared with incubation in water. Inoculum suspensions amended with 0.2% of gorse extract caused more infection and significantly reduced biomass production of 24 wk old gorse plants than suspensions without gorse extract. A minimum number of about 900 viable conidia/infection site of F. tumidum were required to infect gorse leaves. However, incorporation of amendments (which can injure the leaf cuticle) or provision of nutrients (i.e. gorse extract or glucose) in the formulation might decrease the number of conidia required for lesion formation. Scanning electron micrographs showed that germ tube penetration of gorse tissue was limited to open stomata which partly explain the large number of conidia required for infection. The flowers and leaves were more susceptible to F. tumidum infection than the spines, stems and pods. An experiment to determine the number of infection sites required to cause plant mortality showed that the entire plant needs to be inoculated in order for the pathogen to kill 10 wk old plants as F. tumidum is a non systemic pathogen. The number of infection sites correlated strongly with disease severity (R² = 99.3%). At least 50% of the plant was required to be inoculated to cause a significant reduction in shoot dry weight. F. tumidum, applied as soil inoculant using inoculated wheat grains in three separate experiments, significantly suppressed gorse seedling emergence and biomass production. In experiments to determine the loading capacity of the insect species, E. postvittana, the largest insect species studied, carried significantly more (68) and deposited significantly more (29) F. tumidum conidia than the other species. Each E. postvittana, loaded with 5,000 conidia of F. tumidum, transmitted approximately 310 conidia onto gorse plants but this did not cause any infection or affect plant growth as determined by shoot fresh weight and shoot height. E. postvittana on its own did not cause any significant damage to gorse and did not enhance F. tumidum infection. It also failed to spread the pathogen from infected plants to the healthy ones. There was no evidence of synergism between the two agents and damage caused by the combination of both E. postvittana and F. tumidum was equivalent to that caused by F. tumidum alone. This study has shown that E. postvittana has the greatest capacity to vector F. tumidum since it naturally carried the largest and the most fungal spores (429 CFU/insect). Moreover, it naturally carried Fusarium spp. such as F. lateritium, F. tricinctum and Gibberella pulicaris (anamorph Fusarium sambucinum) and was capable of carrying and depositing most F. tumidum conidia on agar. Coupled with the availability of pheromone for attracting the male insects, E. postvittana may be a suitable insect vector for delivering F. tumidum conidia on gorse using this novel biocontrol strategy. Although it is a polyphagous insect, and may visit non-target plants, F. tumidum is a very specific pathogen of gorse, broom and a few closely related plant species. Hence, using this insect species to vector F. tumidum in a biological control programme, should not pose a significant threat to plants of economic importance. However, successful control of gorse using this "lure-load-infect" concept would depend, to a large extent on the virulence of the pathogen as insects, due to the large size of F. tumidum macroconidia, can carry only a small number of it.
178

Mitochondrial Dna (mtdna) Haplogroup Composition In Turkish Sheep Breeds

Yuncu, Eren 01 January 2009 (has links) (PDF)
In the present study, haplogroup composition of five native Turkish sheep breeds, (Karayaka, Akkaraman, G&ouml / k&ccedil / eada, Dagli&ccedil / , Morkaraman) and two sheep breeds from neighboring countries (Herik from Iran, samples from Azerbaijan) were determined by single strand length polymorphism (SSCP) analysis of mitochondrial DNA (mtDNA) NADH dehydrogenase subunit 4 (ND4) region and restriction fragment length polymorphism (RFLP) analysis of mtDNA control (CR) region. Results of the SSCP and RFLP approaches were found to be 96,82% consistent. Most of the 3,18% inconsistency was due to unidentified band patterns of 9 individuals. SSCP method could identify haplogroups A, B and C, but not D and E. Similarly RFLP method could identify haplogroup A, B and possibly D, but not E and C. Data of the present study were compared with those of the previous studies to test the robustness of results under different samplings and were found to be homogenous with a previous study with similar sampling strategy. Neighbor joining tree, principal component analysis (PCA), Delaunay network analysis and analysis of molecular variance (AMOVA) were employed to analyze the haplogroup frequencies and breeds were separated in four groups according to the genetic barriers between breeds from different geographical locations. Strongest differentiation was present between two groups which were eastern breeds (Morkaraman, Herik-Iran and Azerbaijan) and western breeds (G&ouml / k&ccedil / eada, Akkaraman, Karayaka and Dagli&ccedil / ). Additionally, Azerbaijan was proposed as the entrance point of the haplogroup A and the Iran was proposed as the entrance point of haplogroup C to Anatolia with the Spearman rank correlation test.
179

Microbial Landscapes of Corals and Ctenophores

Daniels, Camille Arian 01 January 2011 (has links)
As technology and engineering allow mankind to survey nature at finer scales, the importance of bacteria has been elucidated in their metabolic diversity, ability to transfer genetic information, involvement in biogeochemical cycling, and sheer abundance. With an individual domain of life unto themselves, this diverse group of microorganisms plays an integral role in facilitating life on land and in the oceans, and is second only to viruses in abundance on Earth. They carve niches in a wide range of environments, including those inhospitable to other life forms, and reside in concert or to the detriment of other microbes and/or hosts they inhabit. Solely culturing microorganisms has proven to severely underestimate microbial numbers, capturing less than 1% of marine microbes. However, the advent of molecular methods has revealed the ubiquity, abundance, and diversity of bacteria. Higher organisms have evolved varying degrees of ecological relationships with bacteria, ranging from mutualism to parasitism. As the microbial players are elucidated, determining the specificity and functional roles of these bacteria is a critical and exciting scientific question. The microbiome of corals is an interesting model of complexity, with the animal host striving to maintain a delicate symbiosis, and using its microbiota to assist in nutrient cycling and protection. A contrasting example to the well-studied cnidarians are ctenophores, gelatinous organisms that are globally distributed in the world's oceans, yet the literature contains few studies on microbiota associated with this unique group of animals. Since ctenophores are one of the earliest diverging, extant multicellular animals, these unique organisms could prove to be a better model system than cnidarians. The first project in this dissertation examined spatial structure of bacteria across wild, healthy colonies of the coral Montastraea annularis. Microscale heterogeneity of the bacterial community was observed in coral mucus samples collected tens of centimeters apart on the same coral colony, which has implications for sampling strategies in microbiological studies, and impacts the application of the bacterial community as a proxy for determining coral condition in coral restoration projects. The second project looked at the linkages between coral bacterial community composition and zooxanthellae clade in Pocillopora damicornis, and results suggested that clade is not a major factor in influencing coral bacterial community composition. Sample location was also considered in the P. damicornis bacterial surveys and determined to be driving community structure. The third project is the first study to describe bacteria associated with ctenophores (Mnemiopsis leidyi and Beroe ovata). The ctenophores contained bacterial communities that were distinct from the surrounding water column, and temporal variability was exhibited by bacteria associated with the ctenophores. Exploring microbial landscapes in cnidarians and ctenophores to understand microbial roles in health and disease is the uniting theme of the three separate projects that will be discussed in this dissertation.
180

Characterization of the Bacterial Communities of the Tonsil of the Soft Palate of Swine

Kernaghan, Shaun 04 January 2014 (has links)
Terminal restriction fragment length polymorphism (T-RFLP) analysis and pyrosequencing were used to characterize the microbiota of the tonsil of the soft palate of 126 unfit and 18 healthy pigs. The T-RFLP analysis method was first optimized for the study of the pig tonsil microbiota and the data compared with culture-based identification of common pig pathogens. Putative identifications of the members of the microbiota revealed that the phyla Firmicutes, Proteobacteria and Bacteroidetes were the most prevalent. A comparison of the T-RFLP analysis results grouped into clusters to clinical conditions revealed paleness, abscess, PRRS virus, and Mycoplasma hyopneumoniae to be significantly associated with cluster membership. T-RFLP analysis was also used to select representative tonsil samples for pyrosequencing. These studies confirmed Actinobacteria, Bacteroidetes, Firmicutes, Fusobacteria, and Proteobacteria to be the core phyla of the microbiota of the tonsil of the soft palate of pigs. / OMAFRA Animal Health Strategic Investment

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