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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.
31

Filogenia e taxonomia de percevejos-cavadores do gênero Cyrtomenus Amyot & SERVILLE (HEMIPTERA: CYDNIDAE), pragas de diferentes culturas na Américas do Sul

Avendaño Forero, José Mauricio January 2017 (has links)
A família Cydnidae inclui espécies de percevejos-cavadores, tem distribuição mundial, com mais de 750 espécies em 93 gêneros, divididos em cinco subfamílias. São fitófagos e a maioria das espécies provavelmente polífagas, com algumas espécies que causam danos a diferentes culturas na região Neotropical. Embora a taxonomia de Cydnidae seja considerada bem compreendida, muitos estudos básicos sobre os táxons da região Neotropical ainda precisam ser desenvolvidos. Para algumas espécies, vários registros têm sido errôneos e a correta identificação é essencial para definir e delinear estudos sobre eles, bem como eventuais medidas de controle. Em alguns casos, a taxonomia ao nível de espécie ainda aguarda revisão e é provável que novas espécies ainda precisem ser descritas. A subfamília Cydninae é a que apresenta o maior número de espécies e inclui o gênero Cyrtomenus Amyot & Serville com oito espécies reconhecidas até este trabalho, divididas em dois subgêneros: C. (Cyrtomenus) ciliatus (Perty) [espécie tipo], C. (Cyrtomenus) bergi Froeschner, 1960; C. (Cyrtomenus) crassus Walker, 1867; C. (Cyrtomenus) mirabilis (Perty, 1830); C. (Syllobus) emarginatus Stål, 1862; C. (Syllobus) grossus Dallas, 1851; C. (Syllobus) marginalis Signoret, 1881, e C. (Syllobus) teter (Spinola, 1837). A distribuição do gênero inclui praticamente toda América continental, desde os Estados Unidos até o Uruguai e Argentina. As espécies de Cyrtomenus se destacam pela combinação dos seguintes caracteres compartilhados: ausência de uma estria transversal completa na margem anterior do pronoto, tíbias posteriores achatadas dorso-ventralmente e com espinhos muito desenvolvidos, segundo segmento do rostro simples. No entanto tais características não são únicas entre os cydníneos, e a monofilia do gênero e dos subgêneros nunca foram testadas. Além disso, questões taxonômicas na identificação das espécies ainda dificultam a delimitação do gênero e o desenvolvimento de outros estudos, tanto na área básica (por ex. biogeografia) como aplicada (por ex. monitoramento e controle). As espécies C. bergi e C. mirabilis são consideradas pragas e amplamente distribuídas, ocorrendo desde o sul do México até Brasil e Argentina. No entanto a identidade destas espécies ainda não tem uma boa resolução, baseada na proporção da distância ocelo-olho em relação à largura do ocelo (menor em C. mirabilis e maior em C. bergi) e pelo nível de rugosidade da superfície das jugas (muito rugosa em C. mirabilis, pouco rugosa em C. bergi). Este trabalho teve como objetivos 1) fazer atualização da diversidade taxonômica da subfamília Cydninae no Brasil; 2) revisar Cyrtomenus a partir do estudo morfológico; 3) testar a monofilia do gênero e dos subgêneros; 4) estabelecer a identidade de C. bergi e C. mirabilis; 5) confeccionar mapas de distribuição e chaves para a identificação dos gêneros de Cydninae Neotropical e das espécies incluídas em Cyrtomenus. Uma nova espécie, Tominotus ondulatus nov. sp. é descrita de Cidreira, Rio Grande do Sul, Brasil. Novos registros de espécies ampliaram o número de espécies de Cydninae no Brasil para 47, o que corresponde a mais da metade da diversidade do grupo na região Neotropical. O estudo da morfologia da genitália, dados de distribuição, morfometria linear e geométrica suportam a conclusão que C. bergi é sinônimo júnior de C. mirabilis. A monofilia de Cyrtomenus é parcialmente suportada, suas espécies sempre incluídas em um clado junto com Prolobodes; as espécies destes dois gêneros compartilham a tíbia posterior fortemente achatada, característica única entre os cidnineos Neotropicais. Os resultados não suportam o reconhecimento de dois subgêneros dentro de Cyrtomenus. / The Cydnidae includes species of burrower-bugs and has a worldwide distribution, with more than 750 species in 93 genera, divided into five subfamilies. The species are phytophagous and most species are probably polyphagous, with some species causing damage to different crops in the Neotropical region. Although the taxonomy of Cydnidae is considered well understood, many basic studies in the Neotropical region still need to be done. For some species, several records have been erroneous and proper identification is essential for defining and delineating comparative and general biological studies, as well as eventual control measures. In some cases, taxonomy at the species level is still awaiting review, and it is very likely that new species still need to be described. The subfamily Cydninae is the most speciose taxa and includes the genus Cyrtomenus Amyot & Serville, with 8 species recognized until this work, divided into two subgenres: C. (Cyrtomenus) ciliatus (Perty), C. (Cyrtomenus) bergi Froeschner, 1960; C. (Cyrtomenus) crassus Walker, 1867; C. (Cyrtomenus) mirabilis (Perty, 1830); C. (Syllobus) emarginatus Stål, 1862; C. (Syllobus) grossus Dallas, 1851; C. (Syllobus) marginalis Signoret, 1881, and C. (Syllobus) teter (Spinola, 1837). The distribution of the genus includes practically all continental America, from the United States to Uruguay and Argentina. The species of Cyrtomenus are distinguished by the combination of the following shared characters: absence of a complete transverse stria in the anterior margin of the pronotum, posterior tibia flattened dorso-ventrally and with well developed spines, second segmento of labium simple. However, such characteristics are not unique among the cydnins, and the monophyly of the genus and subgenus included have never been tested. In addition, taxonomic issues in species identification still hamper the delimitation of the genus. The species C. bergi and C. mirabilis are considered pests and widely distributed, occurring from southern Mexico to Brazil and Argentina. However, the identity of these species still does not have a good resolution, and are based on the proportion of the ocellar-eye distance in relation to the width of the ocellus (smaller in C. mirabilis and larger in C. bergi) and by the level of surface roughness of the juga (rugose in C. mirabilis, slightly rough in C. bergi). This work aimed to 1) update the taxonomic diversity of the Cydninae subfamily in Brazil; 2) review the taxonomy of Cyrtomenus using morphological data; 3) to test the monophyly of the genus and subgenera; 4) to establish the identity of C. bergi and C. mirabilis; 5) to make distribution maps and identification keys to all genera of Neotropical Cydninae and species included in Cyrtomenus. A new species, Tominotus ondulatus nov. sp. is described from Cidreira, Rio Grande do Sul, Brazil. New species records increased the number of Cydninae species in Brazil to 47, which corresponds to half the diversity of the group in the Neotropical region. The use the morphology of the genitalia, distribution ranges, linear and geometric morphometric supported C. bergi as a junior synonym of C. mirabilis. The monophyly of Cyrtomenus is partially supported, its species always recognized in a clade with Prolobodes Amyot & Serville; species of these two genera share the posterior strongly flattened, a unique derived characteristic among Neotropical cydnins. The recognition of two subgenera within Cyrtomenus is not corroborated.
32

Importância da investigação farmacológica de Mirabilis jalapa Linn validação de sua utilização

ROCHA, Laurimar Thomé da January 2006 (has links)
Made available in DSpace on 2014-06-12T16:32:32Z (GMT). No. of bitstreams: 2 arquivo6451_1.pdf: 1285930 bytes, checksum: a1dba4731acaffddfe2386346a59f111 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / Mirabilis jalapa Linné, família das Nictagináceas, é uma planta herbácea ereta, profundamente ramificada, de folhas simples ovais, caule tipo haste, com flores pequenas, cálices apicais e pétalas que podem ser brancas, vermelhas, róseas, rôxas ou com tons multicoloridos. Nativa da América Tropical, sendo amplamente cultivada com fins decorativos no Brasil, onde é conhecida como bonina ou maravilha e encontrada da Bahia ao Paraná. Seu uso é difundido na medicina tradicional de muitos países para o tratamento de infecções, inflamação, edemas, conjuntivite, sendo também empregada como diurética, purgativa, tônica, antiespasmódica, vermífuga e antifúngica. Em sua composição fitoquímica relata-se a presença de alcalóides, flavonóides, triterpenóides e esteróides. Devido à diversidade do seu uso popular, buscou-se validar essas informações etnobotânicas, procurando dar suporte científico ao verificado na medicina tradicional. O trabalho teve como objetivo avaliar a toxicidade aguda e farmacológica (antiinflamatória e anti-tumoral em roedores) do extrato das folhas de Mirabilis jalapa em sua fração hexânica. Os ensaios de toxicidade aguda foram realizados por via intraperitoneal, com observações das respectivas alterações comportamentais para cada dose administrada. As doses utilizadas foram 1,0 a 3,0 g/kg, onde foram observados efeitos estimulantes nos primeiros 20 minutos após a administração do extrato hexânico e, em seguida, observados efeitos depressores. Efeitos como aumento da diurese e excreção fecal, foram relatados durante todo ensaio. A DL50 encontrada foi de 2009,167 mg/kg enquanto que a Concentração Letal (CL50) foi de 788,987 ug/ml, avaliada através de ensaio com Artemia salina Leach, o que permite sua classificação quanto à toxicidade em moderadamente tóxico. Em sua avaliação histopatológica, foram encontradas alterações como: congestão com áreas de necrose focal em fígado, congestão renal tubular, congestão e enfisema pulmonar. Para a atividade antiinflamatória utilizou-se o modelo de edema de pata induzido por carragenina, com a administração do extrato hexânico por via oral (125; 225 e 250 mg/kg) e por via intraperitoneal (62,5; 125; 225 e 250 mg/ kg), em ratas fêmeas. Nos ensaios antiinflamatórios, por via oral, não houve diminuição considerável dos volumes do edema da pata dos ratos, enquanto por via intraperitoneal, ocorreram inibições significativas somente na fase final da inflamação. A avaliação antitumoral do extrato hexânico de Mirabilis jalapa Linn frente ao Sarcoma 180 e Carcinoma de Ehrlich por via intraperitoneal (100; 125; 225 e 250 mg/kg) apresentou significativa redução do peso médio dos tumores dos grupos tratados, com índices relevantes de inibição tumoral. Os estudos histopatológicos revelaram foram as seguintes alterações: congestão hepática, atrofia da polpa branca no baço, enfisema pulmonar e atrofia glomerular nos rins, além da presença de metástases principalmente, nos grupos controle e nas doses menos concentradas
33

‘Allelofertile’ soil islands self-conditioned by Welwitschia mirabilis in the Namib Desert

Shabaan, Dalia H. 07 1900 (has links)
Under the extreme arid conditions of deserts, long periods of drought, nutrient-poor soils and high temperatures severely challenge the primary productivity of the ecosystem. Desert plants have evolved morphological and physiological adaptations against abiotic stresses. Along with these adaptation strategies they can recondition their surrounding soil, which will result in the enrichment of nutrients and moisture in the soil surrounding the plant. Although such self-fertilization may support the growth of other sympatric plant species under the plant, competitive exclusion mechanisms (i.e., allelopathy) reduce this possibility. Consequently, this will affect the diversity and functionality of the edaphic microbial communities. I hypothesize that desert xerophytes recondition the soils surrounding their body along with combining the ‘fertility’ and ‘allelopathy’ mechanisms to create a favorable new niche in desert ecosystem. I tested this hypothesis on the soil reconditioned by Welwitschia mirabilis growing in its native environment, the Namib Desert, Namibia. The collected soils were first used to confirm that Welwitschia manipulates the surrounding soil creating a ‘fertile’ but ‘exclusive’ soil area around the plant. Along with evaluating the effect of the reconditioned soil on the germination and plant development under normal irrigation and controlled drought condition, using barley as phytometer. The physio-chemical (i.e., WHC and WP) and microbial community analyses demonstrate that W. mirabilis reconditions the surrounding soil creating an environmental gradient around itself, in which the fertility is increased, through the accumulation and incorporation of shed reproductive parts of the plants (i.e., cones) in the surrounding soil, that will stimulate the plant growth under drought stress. Along with the fertilization effect, soil reconditioning also favor the antagonist effect (i.e., allelopathy) against plant competitors (e.g., new germinating seeds) to protect its ecological niche. Furthermore, the microorganisms and/or soluble/thermolabile molecules contribute to the allelopathic effect activated by the soil-reconditioning around W. mirabilis. The interactions among W. mirabilis, soil and microbes highlight an adaptive strategy that combines soil fertilization and allelopathy that I defined as “Alleolofertility” strategy. This allelofertility island surrounding the W. mirabilis may contributes to explain the evolutionary success of such a ‘living fossil’.
34

Comparative Functional Analysis and Identification of Regulatory Control in Gene Networks Using the Leucine-Responsive Regulatory protein and its Regulon as a Model System

Lintner, Robert E. 14 May 2007 (has links)
No description available.
35

Les ilôts de résistance de type SGI1 (Salmonella Genomic Island 1) et apparentés dans des souches humaines cliniques de Porteus mirabilis et Salmonella enterica / Salmonella Genomic Island 1 (SGI1) and relative genomic islands from clinical Proteus mirabilis and Salmonella enterica isolates

Goulard de Curraize, Claire 01 December 2017 (has links)
Salmonella genomic island 1 (SGI1) est un élément intégratif mobilisable décrit pour la 1ère fois dans un clone penta-résistant de Salmonella Typhimurium DT104. Depuis, plusieurs variants et îlots apparentés (Proteus genomic island 1 (PGI1)) ont été rapportés dans différents sérotypes de Salmonella enterica et chez Proteus mirabilis. Ces îlots de résistance sont constitués d’un squelette plutôt stable et d’une région de multirésistance (MDR) variable. L’objectif de cette thèse était d’étudier ces îlots dans des souches cliniques de P. mirabilis (CHU de Dijon et Lariboisière à Paris) et de S. enterica (CHU de Dijon). La prévalence de ces îlots variait de 5 à 16% chez P. mirabilis ayant acquis au moins une résistance. L’étude génotypique a montré une grande diversité des souches mais également la présence de quelques clones porteurs de SGI1 ou PGI1. Le séquençage de ces îlots a mis en évidence la grande plasticité des régions MDR souvent en lien avec des mouvements d’IS26. Ces dernières permettent à la région MDR de s’enrichir en nouveaux gènes de résistance (ex : blaCTX-M-15) présents dans des structures antérieurement décrites sur des plasmides de clones d’entérobactéries répandus. De nombreuses espèces d’entérobactéries porteuses d’un plasmide IncA/C sont capables d’acquérir par conjugaison un îlot provenant d’une autre entérobactérie. Cet îlot s’intègre alors au niveau du site chromosomique spécifique (trmE). Sous pression antibiotique et en présence d’un plasmide IncA/C, les souches peuvent être complètement excisées de leur îlot. Ainsi, ces îlots sont des interfaces de résistance à la fois stables mais aussi dynamiques favorisant la dissémination des gènes de résistance. Une virulence accrue par la présence de ces îlots chez S. enterica n’a pas pu être confirmée ni dans le modèle d’infection expérimentale de C. elegans, ni dans une étude rétrospective chez l’homme (prévalence de 12%). En revanche, P. mirabilis avait tendance à être plus pathogène chez C. elegans lorsqu’il était porteur d’un îlot / Salmonella genomic island (SGI1) is an integrative mobilizable element initially described in an epidemic multidrug-resistant Salmonella Typhimurium DT104. Since this first report, many variants and related genomic islands (Proteus genomic island 1 (PGI1)) have been described among Salmonella enterica serovars and in Proteus mirabilis. These islands have a stable backbone and a highly variable multidrug-resistant (MDR) region. The objective of this work was to study SGI1 from clinical P. mirabilis isolates (University hospitals of Dijon and Lariboisière - Paris) and S. enterica (University hospital of Dijon) The prevalence of these islands ranged from 5% to 16% in P. mirabilis with at least one acquired resistance. The genotypic analysis revealed a wide diversity among isolates but also the presence of some clonal isolates harbouring SGI1 or PGI1. Genomic island sequencing revealed the great plasticity of MDR regions, primarily mediated by IS26. Thanks to IS26 movements, the MDR region gains resistance genes (such as blaCTX-M-15) present in structures initially detected in plasmids from widely distributed Enterobacteriaceae. Many species of Enterobacteriaceae that harbour IncA/C plasmids are able to acquire islands by conjugation. These islands are then incorporated into specific sites on the chromosome (trmE). They could also be completely excised from Enterobacteriaceae under antibiotic pressure in the presence of an IncA/C plasmid. Genomic islands should be regarded on the one hand as a steady interface of resistance and on the other hand as a dynamic interface conveying resistance genes. Finally, SGI1 of S. enterica was not found to increase virulence in a Caenorhabditis elegans model or in a retrospective clinical study (12% of prevalence). However, it seems that P. mirabilis becomes more virulent when it harbours SGI1 in Caenorhabditis elegans
36

Infecção urinária comunitária: aspectos epidemiológicos, clínicos e laboratoriais em crianças e adolescentes / Community-acquired urinary tract infection: epidemiological, clinical and laboratory aspects in children and adolescents

Lo, Denise Swei 31 October 2017 (has links)
INTRODUÇÃO: Infecção do trato urinário (ITU) é doença cujos sinais e sintomas são frequentemente inespecíficos, especialmente em lactentes. Portanto, o conhecimento de seus aspectos epidemiológicos, clínicos e laboratoriais são relevantes para a adequada abordagem clínica. OBJETIVOS PRINCIPAIS: Descrever: a prevalência de ITU como motivo de atendimento em pronto-socorro geral de Pediatria; a variabilidade da frequência de ITU e dos agentes etiológicos em diversas faixas etárias e sexo; o perfil de sensibilidade antimicrobiana de Escherichia coli; o quadro clínico, laboratorial e evolutivo de lactentes jovens. OBJETIVOS SECUNDÁRIOS: Cálculo de sensibilidade, especificidade, valor preditivo positivo e valor preditivo negativo do corte de leucocitúria >= 10.000 leucócitos/mL para o diagnóstico de ITU em lactentes jovens. Comparar as diferenças de ITU por Escherichia coli e Staphylococcus saprophyticus em adolescentes do sexo feminino e discutir as melhores escolhas de terapia antimicrobiana empírica para uso na população estudada. MÉTODO: Estudo retrospectivo, descritivo, incluindo todos os casos de ITU (urocultura quantitativa com >= 50.000 UFC/mL por sondagem vesical ou >= 100.000 UFC/mL por jato médio) atendidos no Pronto-Socorro de Pediatria do Hospital Universitário da Universidade de São Paulo, de 01/01/2010 a 31/12/2012, idades entre zero a 15 anos incompletos. Resultados: Do total de 188.460 atendimentos realizados, 7994 colheram urocultura por suspeita de ITU; este diagnóstico foi confirmado em 1071 casos (prevalência: 0,57% do total de atendimentos e 13,4% das uroculturas incluídas). A proporção de casos entre sexo masculino e feminino foi: 1:0,3 em menores de três meses; 1:3,9 entre três meses a 12 anos e 1:12 entre 12 a 15 anos. Escherichia coli foi o principal agente responsável por 73,2% dos casos totais de ITU. Entretanto, outros agentes importantes foram Klebsiella pneumoniae (18,46%) e Enterococcus faecalis (7,7%) em lactentes jovens (menores de três meses de idade); Proteus mirabilis (30,8%) em meninos de três meses a 12 anos; Staphylococcus saprophyticus (25%) em adolescentes do sexo feminino entre 12 a 15 anos. A sensibilidade antimicrobiana de Escherichia coli foi observada acima de 80% para: amoxicilina/ácido clavulânico (87%), cefuroxima (98%), cefotaxima (98%), ceftriaxona (100%), cefepime (99%), amicacina (100%), gentamicina (97%), ciprofloxacina (98%), norfloxacina (94%), ácido nalidíxico (93%) e nitrofurantoína (97%). Em lactentes jovens, febre sem sinais localizatórios foi o sintoma mais frequente de ITU (77,8%). Exames subsidiários de hemograma e proteína C reativa foram de pouca utilidade clínica. O teste de nitrito positivo apresentou baixa sensibilidade: 30,8% (IC 95%: 19,9%-43,4%), porém elevada especificidade e valor preditivo positivo. Enquanto que o corte de leucocitúria > 10.000 leucócitos/mL para ITU revelou boa sensibilidade: 87,7% (IC 95%: 77,2%-94,5%), porém baixa especificidade e valor preditivo positivo. Nas adolescentes do sexo feminino entre 12 a 15 anos, houve menor positividade do teste do nitrito nas ITU por Staphylococcus saprophyticus do que nas ITU por Escherichia coli. Na população do presente estudo, a terapia empírica inicial recomendada seria: zero a três meses: tratamento parenteral com aminoglicosídeo ou cefalosporina de terceira geração; podendo associar ampicilina para cobertura de Enterococcus faecalis. Entre três meses a 15 anos: amoxicilina/ácido clavulânico ou cefuroxima ou ceftriaxona ou aminoglicosídeos. CONCLUSÕES: ITU é doença frequente em atendimentos de pronto-socorro. Os aspectos epidemiológicos, clínicos e laboratoriais são variáveis nas diversas faixas etárias e sexos; portanto, a abordagem deve ser individualizada em cada um destes segmentos / INTRODUCTION: Urinary tract infection (UTI) frequently presents with nonspecific signs and symptoms, particularly in infants. Therefore, the understanding of its epidemiological, clinical and laboratory aspects are relevant to its appropriate clinical approach. MAIN OBJECTIVES: To describe: the prevalence of UTI as a cause for attending the pediatric emergency department; the variability of the frequency of UTI and etiological agents in different age groups and sexes; the antimicrobial sensitivity profile of Escherichia coli; the clinical features, laboratory findings and treatment outcomes in young infants. SECONDARY OBJECTIVES: To evaluate sensitivity, specificity, positive predictive value and negative predictive value of pyuria >= 10,000 leukocytes/mL for screening UTI in young infants. To compare UTI due to Escherichia coli with UTI due to Staphylococcus saprophyticus in female adolescents and to discuss the best empirical antimicrobial treatment in the population studied. METHODS: Retrospective, descriptive study, including all cases of UTI (urine culture of >= 50,000 CFU/mL obtained by bladder catheterization or >= 100,000 CFU/mL obtained by midstream-voided method) attended at the pediatric emergency department of University Hospital of the University of São Paulo, from 01/01/2010 to 12/31/2012, ages from zero to 15 years old. Results: Of 188,460 visits in this period, 7994 collected urine culture on suspicion of UTI. This diagnosis was confirmed in 1071 cases (prevalence: 0.57% of total visits and 13.4% of urine cultures included). The proportion of cases between male and female was: 1: 0.3 in children younger than three months old; 1: 3.9 from three months to 12 years old and 1:12 from 12 to 15 years old. Escherichia coli was the main etiology responsible for 73.2% of total cases of UTI. However, other important agents were Klebsiella pneumoniae (18.46%) and Enterococcus faecalis (7.7%) in young infants (under three months of age); Proteus mirabilis (30.8%) in boys from three months to 12 years old; Staphylococcus saprophyticus (25%) in female adolescents aged 12-15 years. The antimicrobial sensitivity of Escherichia coli was still above 80% for amoxicillin / clavulanic acid (87%), cefuroxime (98%), cefotaxime (98%), ceftriaxone (100%), cefepime (99%), amikacin (100%), gentamicin (97%), ciprofloxacin (98%), norfloxacin (94%), nalidixic acid (93%) and nitrofurantoin (97%). In young infants, the absence of another source of fever was the most frequent UTI symptom (77.8%). Laboratory parameters including peripheral white blood cell count and C-reactive protein concentration were of limited clinical usefulness. The sensitivity of nitrite testing for bacteriuria was low: 30.8% (95% CI: 19.9%-43.4%), but had high specificity and positive predictive value. Pyuria> 10,000 leukocytes / mL for identifying UTI had high sensitivity: 87.7% (95% CI: 77.2%-94.5%), but low specificity and positive predictive value. In female adolescents aged 12 to 15 years old, there were few positive nitrite tests in UTI due to Staphylococcus saprophyticus compared with UTI due to Escherichia coli. In the population studied, the initial empirical therapy recommended would be: from zero to three months old: parenteral treatment with aminoglycoside or third generation cephalosporin; it could be associated with ampicillin to treat Enterococcus faecalis. Between three months to 15 years old: amoxicillin / clavulanic acid or cefuroxime or ceftriaxone or aminoglycosides. In cystitis: in addition to amoxicillin / clavulanic acid or cefuroxime; nitrofurantoin is also a good option for Staphylococcus saprophyticus UTI whereas nalidixic acid is also a nice choice for Proteus mirabilis UTI. CONCLUSIONS: UTI is a common disease in emergency department visits. The epidemiological, clinical and laboratory aspects are variable in the different age and sex groups; therefore, the approach must be individualized in each of these groups
37

Design of integrated processes for a second generation biorefinery using mixed agricultural waste

Dlangamandla, Nkosikho January 2018 (has links)
Thesis (Doctor of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2018. / Lignocellulosic biomass (agro-waste) has been recommended as the most promising feedstock for the production of bioalcohols, in the biofuel industry. Furthermore, agro-waste is well-known as the most abundant organic matter in the agricultural and forestry product processing industry. However, the challenge with utilizing agro-waste as a feedstock is its highly recalcitrant structure, which limits hydrolysis to convert the holocelluloses into fermentable sugars. Conventional pre-treatment methods such as dilute acid, alkaline, thermal, hot water and enzymatic, have been used in previous studies. The challenge with these conventional methods is the generation of residual toxicants during the pretreatment process, which inhibits a high bioalcohol yield, by reducing the microbial populations’ (fermenter) ability to be metabolically proficient during fermentation. Numerous studies have been developed to improve the engineered strains, which have shown to have an ability to reduce the inhibition and toxicity of the bioalcohols produced or by-products produced during pre-treatment, while enhancing the bioalcohol production. In the present study (chapter 5), evaluation of common conventional methods for the pretreatment of the mixed agro-waste, i.e. (˃45µm to <100µm) constituted by Citrus sinensis, Malus domestica peels, corn cobs from Zea mays and Quercus robur (oak) yard waste without a pre-rinsing step at a ratio of 1:1 at 25% (w/w) for each waste material, was undertaken, focusing on hot water pre treatment followed by dilute acid (H2SO4) pre-treatment. To further pretreat the mixed agro-waste residue, cellulases were used to further hydrolyse the pre-treated agro-waste in a single pot (batch) multi-reaction process. The TRS concentration of 0.12, 1.43 and 3.22 g/L was achieved with hot water, dilute acid and cellulases hydrolysis as sequential pretreatment steps, respectively, in a single pot multi-reaction system. Furthermore, a commercial strain was used to ascertain low (C1 to C3) and high carbon content (C4+) bioalcohol production under aerobic conditions. Multiple bioproducts were obtained within 48 to 72 h, including bioethanol and 1-Butanol, 3-methyl, which were major products for this study. However, undesirable bio-compounds such as phenolics, were detected post fermentation. Since multiple process units characterised by chemical usage and high energy intensivity have been utilized to overcome delignification and cellulolysis, a sustainable, environmental benign pretreatment process was proposed using N. mirabilis “monkey cup” fluids (extracts) to also reduce fermenter inhibitors from the delignification of mixed agrowaste; a process with minimal thermo physical chemical inputs for which a single pot multi-reaction system strategy was used. Nepenthes mirabilis extracts shown to have ligninolytic, cellulolytic and xylanolytic activities, were used as an enzyme cocktail to pretreat mixed agro-waste, subsequent to the furtherance of TRS production from the agro-waste, by further using cellulase for further hydrolysis. N. mirabilis pod extracts were determined to contained carboxylesterases (529.41±30.50 U/L), β-glucosidases (251.94±11.48 U/L) and xylanases (36.09±18.04 U/L), constituting an enzymatic cocktail with a significant potential for the reduction in total residual phenolic compounds (TRPCs). Furthermore, the results indicated that maximum concentration of TRS obtainable was 310±5.19 mg/L within 168 h, while the TRPCs were reduced from 6.25±0.18 to 4.26 ±0.09 mg/L, which was lower than that observed when conventional methods were used. Overall N. mirabilis extracts were demonstrated to have an ability to support biocatalytic processes for the conversion of agro-waste to produce fermentable TRS in a single unit facilitating multiple reactions with minimised interference with cellulase hydrolysis. Therefore, the digestive enzymes in N. mirabilis pods can be used in an integrated system for a second generation biorefinery.
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Lipopolysaccharide (LPS) core biosynthesis in "Proteus mirabilis" / Estudio de la biosíntesis del núcleo de lipopolisacarido (LPS) en "Proteus mirabilis"

Aquilini, Eleonora 11 January 2013 (has links)
Urinary tract infection (UTIs) is an extremely common disease. Proteus mirabilis is a common cause of UTI in individuals with functional or structural abnormalities or with long-term catheterization, it forms bladder and kidney stones as a consequence of urease-mediated urea hydrolysis. Known virulence factors, besides urease, are flagella, fimbriae, outer membrane proteins, hemolysins, amino acid deaminase, protease, capsule and lipopolysaccharide (LPS). Study of LPS core is particularly relevant for several reasons: it is a conserved region, although it is increasingly clear that there is some variability at the genus or groups of similar genera, its chemical structure modulates the endotoxic activity of lipid A, alteration of the LPS core, which generates less virulent bacteria, encourages the search of substances that interfere with the biosynthesis of this region, and conserved regions of the core LPS could be useful as antigens in preventing diseases caused by pathogens that contain these conserved regions. The specific aims of this project have been to identify and functionally characterize genes involved in core LPS biosynthesis in P. mirabilis, to elucidate the mechanism of incorporation of galactosamine (GalN) to the core LPS, to identify genes coding for phosphoethanolamine (PEtN) modifications, and to characterize and to study the biological effects of the gene encoding the PEtN transferase involved in the modification of the second heptose residue (L,D-HepII). We found that P. mirabilis has most of the genes for the biosynthesis of LPS core grouped in the waa cluster in the chromosome. Despite this, additional genes required for core LPS biosynthesis are found outside the waa cluster. The pentasaccharide of the inner core, shared by all Enterobacteriaceae, is biosynthesized in P. mirabilis, by the sequential activity of a bifunctional transferase (WaaA) and three heptosyltransferases (WaaC, WaaF, and WaaQ). These enzymes are transcribed from genes located inside the waa cluster, and are conserved in P. mirabilis strains analyzed; for more, they show a high identity and similarity level to homologues proteins of Escherichia coli, Klebsiella penumoniae and Serratia marcescens. The waaL gene, coding for the O-antigen polymerase ligase, is found adjacent to the classic waa cluster. Downstream this gene, four genes encoding enzymes belonging to the 4 (walM, walN, and WalR), and 9 (walO) glycosyltransferase family were found. Even if members of these families were related to LPS core biosynthesis in several Gram-negative bacteria, in P. mirabilis they do not appear to be involved in the biosynthesis of the reported core LPS structures. The presence of the disaccharide hexosamine (HexN)-1,4-galacturonic acid (GalA) is a feature of P. mirabilis LPS outer core. Depending on the nature of the HexN outer core residue, two different homologues for N-acetyl-hexosamine transferases are present in the waa cluster: wabH or wabP. Altought the incorporation of glucosamine into LPS core requires an acetylglucosaminyltransferase (WabH) and a deacetilase (WabN), the incorporation of GalN requires three enzymes: an acetylgalactosaminyltransferase (WabP), a deacetilase (WabN) and an epimerase (gne). An amplification test with specific primers for this two different homologues can be used to predict the HexN nature in P. mirabilis LPS cores. The strain-specific genes wamB and wamC code for a galactosyltransferase and a heptosyltransferase respectively in strain R110 of P. mirabilis. The enzyme encoded by gene wamD is a N-acetylglucosaminyltransferase, and it is found in strain 51/57 of P. mirabilis. WamA, coded by wamA gene in the waa cluster of strains R110, 50/57, TG83 and HI4320, is a heptosyltransferase responsible for the incorporation of a quarter residue of heptose (Hep), in DD configuration, to the GalA II of the outer core. In P. mirabilis strain 51/57, a gene coding a protein of the Mig-14 family was identified inside the waa cluster, this localization appears to be an exception in the Enterobacteriaceae family. Inspection of the whole genome of P. mirabilis HI4320 did not allow the identification of a mig-14 similar gene. There are three putative PEtN transferases in the genome of P. mirabilis: PMI3040, PMI3576, and PMI3104. The gene identified as eptC (PMI3104) transfers the moiety of PEtN to the O-6 position of L,D-Hep II (HepII6PEtN). The absence of the positive charge due to PEtN residue doesn't affect the bacterial growth kinetics in lab conditions in rich or defined media, but causes a moderate destabilization of the outer-membrane. Despite the lack of the PEtN residue on the Hep II in P. mirabilis LPS core, has no statistically effects during urinary tract infection assays in mouse model, the absence of this modification causes an increase sensitivity to complement in non-immune human sera. / P. mirabilis no es una causa frecuente de infecciones urinarias en el huésped normal, más bien infecta el tracto urinario con alteraciones funcionales o anatómicas, o instrumentación crónica como el cateterismo. P. mirabilis está a menudo asociado con cálculos urinarios e incrustaciones de los catéteres y es, particularmente importante, en pacientes con cateterización prolongada. Las infecciones del tracto urinario asociadas a cateterización son mundialmente reconocidas como la causa más común de infección asociada a tratamientos en ambiente hospitalario. El LPS es un factor de virulencia importante en bacterias Gram negativas patógenas. También conocido como endotoxina, es una molécula glicolipídica que constituye la estructura mayoritaria de la cara externa de la membrana externa (OM). En Proteus mirabilis la mayoría de los genes responsables de la biosíntesis de núcleo de LPS están localizados en el cromosoma, en el agrupamiento génico waa. A pesar de esto, algunos genes adicionales, necesarios para la biosíntesis del núcleo de LPS, se encuentran ubicados fuera del agrupamiento génico waa. El pentasacárido del núcleo interno, común a todas las Enterobacteriáceae, se biosintetiza en P. mirabilis, por la actividad secuencial de una transferasa bifunciona (WaaA) y tres heptosiltransferasas (WaaC, WaaF, y WaaQ). La presencia del disacárido HexN‐1,4‐GalA es característica del núcleo externo de LPS en P. mirabilis. Dependiendo de la naturaleza del residuo de HexN, se encuentran, en el agrupamiento génico waa, dos HexNAc transferasas diferentes: wabH o wabP. El gen eptC (PMI3104) codifica para la enzima que transfiere el residuo de fosfoetanolamina a la posición O-6 de la L,D-Hep II (HepII6PEtN), en el núcleo de LPS de P. mirabilis. La ausencia de la carga positiva del residuo de fosfoetanolamina no afecta a la cinética de crecimiento de las bacterias en condiciones standard de laboratorio sea en medios ricos o definidos. La ausencia del residuo fosfoetanolamina provoca una desestabilización moderada de la membrana externa que se traduce en una disminución de la MIC para SDS.
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Étude sur "Lion de Bourges", poème épique du XIVe siècle / Study about "Lion de Bourges", epic poem from XIVth century

Gallois, Martine 02 May 2011 (has links)
L’étude du long poème épique de Lion de Bourges permet de mettre en évidence un parcours individuel modelé par la recherche d’un ordre politique et féodal, au sein duquel le héros tente d’inscrire son action, celle d’un ordre familial, au travers du lignage et de la parentèle, et celle d’un ordre personnel, à la fois recherche des origines et du père, qui devient une quête d’identité. L'idéal chevaleresque s’inscrit donc dans trois perspectives complémentaires. C’est d’abord face à l’instabilité des structures et du pouvoir royal, l’aspiration au rétablissement d’un ordre politique, mais l’inachèvement des actions entreprises et la constante réapparition du mal font que cette quête de l’ordre reste imparfaite. C’est ensuite l’effort pour la restauration d’un ordre familial mis à mal par les entreprises des traîtres et les aléas de l’aventure, mais là encore l’engagement et les efforts du héros ne permettent d’obtenir que des résultats imparfaits ou insatisfaisants. C’est donc à un niveau supérieur, dans la quête d’un ordre intérieur et dans un élan vers la perfection que l’itinéraire personnel de Lion de Bourges peut trouver son véritable sens. Cependant, son ultime tentative pour s’approcher du sacré ne conduit qu’à un échec : le contact avec le surnaturel chrétien est réservé au personnage du Blanc Chevalier, revenant secourable, et le héros doit se contenter d’une forme intermédiaire de merveilleux féerique. En définitive, ce poème témoigne, de manière originale et fort cohérente, de la vision pessimiste de l’idéal humain et de l’engagement héroïque, qui devient prédominante dans l’épopée française tardive. / The long epic poem Lion de Bourges portrays the personal quest of a hero, first, to set in order a feudal political structure; then his own family structure (through ancestry and parentage); and finally, his personal life; for seeking his origins and father becomes a search for his own identity. The chivalric ideal therefore is seen through three complementary perspectives. Initially, when faced with the instability of social structures and royal power, Lion seeks to re-establish political order, but both Lion’s inability to complete his goals and the constant reappearance of evil cause this quest to remain incomplete. Afterwards, Lion’s effort to bring his family back together is derailed by traitors’ plots and the fortunes of adventure, so there again the hero’s efforts produce only imperfect or unsatisfactory results. It is thus only at the highest level, the quest for personal order, for spiritual perfection, that the private itinerary of Lion de Bourges might find its true goal. However, his last desire, to reach sanctity, leads to failure as well: contact with the Christian supernatural is reserved for the White Knight, a helpful spirit, and the hero must content himself with a lesser form of supernatural, the enchanted marvelous world. Clearly, this poem demonstrates, in an original and highly consistent way, the pessimistic view of the human ideal and of heroic engagement that predominates in late French epic.
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Obtenção de derivados semissintéticos triterpênicos do ácido ursólico visando atividade biológica

Vieira, Laura Cardozo January 2013 (has links)
As infecções por bactérias representam um grave problema hoje e para o futuro, devido ao fato de que estes microrganismos desenvolvem mecanismos de resistência aos antibióticos ao longo do tempo de uso. A formação de biofilmes também é um fator a ser discutido no cenário atual por estar associado a muitas infecções bacterianas humanas, principalmente àquelas envolvendo dispositivos médicos aumentando assim os riscos de infecções hospitalares. O ácido ursólico (AU) é um triterpeno conhecido por suas atividades biológicas relatadas. Apresenta moderada atividade antibacteriana, porém tem demonstrado importante citotoxicidade frente a algumas linhagens celulares. Em vista disso, neste trabalho se desenvolveu uma série de novas moléculas derivadas do AU com alterações nas posições C-3 e C-28. Quatro moléculas com substituição em C-3 (derivados 2, 3, 4e 5) e uma com substituição em C-3 e C-28 (derivado 6) foram comparadas ao AU (1) quanto a atividade antibacteriana. As cepas utilizadas foram Salmonela Typhimurium, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, Staphylococcus epidermidis e Staphylococcus aureus. Os compostos 3 e 6 apresentaram melhor perfil inibitório de forma geral, onde 3 apresentouse bactericida para S. aureus e S. epidermidis (Gram positivas) e paraP. mirabilis (Gram negativa) apresentou-se bacteriostático. / The ursolic acid (UA) is a triterpene known for their biological activities reported. Thus, become useful techniques semi-synthesis starting from natural products extracted, for example residue industries in order to improve the pharmacological properties decreasing toxicity. The bacterial infections are a serious problem today and in the future due to the fact that these organisms develop resistance mechanisms to antibiotics over time of use. The formation of biofilms is also a factor to be discussed in the current scenario because of being responsible for a very high number of rejections and other prosthetic devices by increasing the risk of nosocomial infections. The AU has a moderate antibacterial activity reported in the literature, but showed significant cytotoxicity against some cell lines. In view of this it developed a series of new molecules derived from AU residues extracted from apples (Mallus domestica) from the juice industry by promoting the so-called green chemistry. The molecules undergo changes in C-3 and C-28. Four molecules with substitution at C-3 (derived from 2, 3, 4 and 5) and one with substitution at C-3 and C-28 (derived 6) were compared with au (1). The strains used in the tests of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration were Salmonella Typhimurium, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, Staphylococcus epidermidis and Staphylococcus aureus. Compounds 3 and 6 had better inhibitory profile in general, where three presented bactericidal to S. aureus and S. epidermidis (Gram positive) and P. mirabilis (Gram negative) appeared bacteriostatic.

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