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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.
1

Similaridade genética pelo RAPD-PCR de cepas de Staphylococcus sp isolados de portadores humanos e de camas de uma unidade hospitalar

Fabiano, Telma Luciana Trovó [UNESP] 10 December 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-12-10Bitstream added on 2014-06-13T20:24:20Z : No. of bitstreams: 1 fabiano_tlt_dr_jabo.pdf: 373992 bytes, checksum: 54cb0750ac5f6c1287f8733a4da8a103 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foram coletadas 143 amostras de mãos de humanos e camas hospitalares, através de suabes em caldo BHI (Brain Heart Infusion), em um Hospital Escola de Ribeirão Preto, SP. Este trabalho teve como objetivo caracterizar as cepas de Staphylococcus sp e verificar o grau de similaridade genética entre as cepas pelo RAPD-PCR e analisar o perfil de resistência a diversos antimicrobianos. As amostras coletadas foram incubadas a 37º C por 24 horas e após este período as culturas foram semeadas em placas de Petri contendo agar “Staphylococcus Médium 110”. As colônias típicas do gênero Staphylococcus foram coletadas e estocadas a 4º C até o momento de elaboração das provas de produção de catalase e coagulase, fermentação do manitol, DNAse e hemólise. As cepas isoladas foram analisadas através da técnica de RAPD-PCR para verificar o grau de similaridade. A sensibilidade das cepas isoladas foi testada frente a 11 diferentes antibióticos. Foram isoladas 92 cepas de Staphylococcus sp sendo 67 (72,8%) cepas de Staphylococcus coagulase negativas e 25 (27,2%) cepas de Staphylococcus coagulase positivas. A análise de similaridade mostrou heterogeneidade genética entre as cepas. Foram encontradas oito (8.7%) cepas de Staphylococcus sp resistentes à vancomicina, sendo uma multirresistente a todos os antibióticos. Introduzir medidas de assepsia nas mãos de pessoal e leitos hospitalares e a racionalização do uso indiscriminado de antibióticos muito contribuirá para diminuição das infecções nosocomiais. / A total of 143 samples were analyzed in this study. These included samples from human hands and hospital beds at a Medical Teaching Hospital of Ribeirão Preto, SP. This study aimed to characterize the strains of Staphylococcus sp and verify the degree of genetic similarity between the strains by RAPD-PCR and analyse the profile of the various antimicrobial resistance. Swabs samples were collected and cultured in brain heart infusion medium at 37o C for 24 h. Further cultivation was performed on Staphylococcus medium 110 agar plates. Typical colonies representing Staphylococcus genus were collected and stored at 4º C until it was used for identification tests, which included catalase, coagulase and mannitol production, hemolysis and Dnase. Isolates were analyzed by RAPD-PCR to verify similarity level. Antibiotic susceptibility was determined using 11 different antibiotics. A total of 92 Staphylococcus sp strains were isolated, whereas 67 (72.8%) were coagulase-negative Staphylococcus strains and 25 (27,2%) were coagulase-positive Staphylococcus strains. Similarity analysis revealed a great dissimilarity among isolates. High percentage of beta-lactams resistant Staphylococcus sp was found. Eight strains (8.7%) were vancomycin-resistant. A high percentage of multiresistant strains were found. Introduce of good hygiene practices for hands and hospital beds and adequate antibiotic use, may contribute to reduction of nosocomial infection and consequently improved antibiotic treatment response.
2

Extra-pair paternity within the female-defense polygyny of the lizard, Anolis carolinensis: Evidence of alternative mating strategies

Passek, Kelly Marie 15 July 2002 (has links)
Mate competition is a prominent component of sexual selection theory. Typically, males attempt to mate with the most females possible and females attempt to mate with the highest quality males possible. In the polygynous female-defense mating system of Anolis carolinensis, males compete directly for females through territorial behavior. Inter-male competition is intense due to an average polygyny ratio of 1 male to 3 females despite a 1:1 adult sex ratio. Through high levels of territorial behavior (e.g., 100 displays/h, 27 m patrol distances/h, 70% of day in defense-related activities), males attempt to exclude other males from resident females who, in turn, both store sperm and ovulate a single-egg clutch at weekly intervals over a 4-month breeding season. Paternity of hatchlings in 16 naturally occurring breeding groups was analyzed to determine the extent to which the territorial resident male was able to prevent other males from fathering offspring of his resident females. Lizards residing in or neighboring a resident male's territory were collected and RAPD-PCR was used to determine the paternity of hatchlings. Of the 48 hatchlings from 26 females, resident territorial males fathered 52% of hatchlings; 15% were fathered by a male whose territory bordered that of the resident male and 21% were fathered by a smaller male living covertly within the resident male's territory. Paternity for the remaining 12% of hatchlings belonged to an unsampled male. Given that females mated with multiple males, laboratory-based controlled matings were conducted where females were sequentially paired with two males and RAPD-PCR was used to analyze which of the two males fathered the subsequent hatchlings to determine the mechanism of sperm precedence. Regardless of mating order, only one male of the pair fertilized the eggs. Male A. carolinensis have reproductive strategies present in addition to defending resident females and female A. carolinensis have options in addition to simply mating with the resident male. While sperm precedence is present in this species, it is not based on mating order, but may involve both the number of sperm deposited in the female's tract as well as the quality of those sperm. / Ph. D.
3

Biochemical Separation of Geographical Strains of Plum Curculio, Conotrachelus nenuphar (Herbst) (Coleoptera: Curculionidae), and Evaluation of Olfactory Attractants in Virginia Orchards

McClanan, Michelle Erin Garlic 14 August 2002 (has links)
Plum curculio, Conotrachelus nenuphar (Herbst), is an endemic pest of stone and pome crops of the eastern United States. Two morphologically identical strains of plum curculio have been described and documented in Virgina: a univoltine strain and a multivoltine strain. Because of the cryptic coloring and behaviours of the plum curculio adults, monitoring in orchards is difficult and often ineffective. RAPD-PCR assay was an effective method for separation of the geographical strains. Of the tested primers four, OPE 01, OPE 03, OPE 04, and OPE 07, gave 21 amplimers that are useful for distinguishing individuals from the univoltine and multivoltine populations. Gene targeted PCR revealed the presence of Wolbachia in both populations. Analysis of the wsp gene sequence showed the univoltine population of plum curculio is associated with a strain of Wolbachia in supergroup B, most closely related to a strain identified from Perithemis tenera (Say) (Odonata). The multivoltine populations of plum curculio are associated with strains of Wolbachia which are in supergroup A, and most closely related to Wolbachia strains associated with Dacus destillatoria, Bactrocera sp., and Callosobruchus chinensis Linn. Three different trap designs baited with grandisoic acid, plant volatiles, and a combination of pheromone and plant volatiles were tested. In 1999, significantly more plum curculios were captured with Tedders traps baited with grandisoic acid and unbaited control in traps baited with limonene, plum essence or ethyl isovalerate. In 2000, Circle traps baited with plum essence, sour cherry essence and grandisoic acid yielded no results. In 2001, branch mimic traps yielded no significant differences among three release rates of a blend of benzaldehyde, ethyl isovalerate, trans-2-hexenal, and limonene; although, there was a significant interaction between the pheromone and the host plant volatiles. Overall however, all three of the traps were not effective. / Master of Science
4

Caracterização genotípica e fenotípica de Candida sp de fluido vaginal de mulheres adultas

Cunha, Keith Cássia da 16 April 2010 (has links)
Made available in DSpace on 2016-01-26T12:51:25Z (GMT). No. of bitstreams: 1 keithcassiadacunha_dissert.pdf: 1691081 bytes, checksum: fab0d44d3deb2f20e40bba856dd1b78f (MD5) Previous issue date: 2010-04-16 / Candida albicans is widely recognized as the pathogen often occurring in vulvovaginal candidiasis. Objective: To compare the genotypes, among infection or colonization and recurrent isolates, with virulence determinants (phospholipase, proteinase, amylase, gelatinase, haemolysin, thermotolerance and biofilm), and to in vitro antifungal susceptibilities. Methods: 317 samples of vaginal fluid of were collected from women with or without symptomatic indications to VVC, including vaginal itching, abnormal discharge, soreness and dyspareunia to mycological investigation. The antimicrobial susceptibility was evaluated for 4 drugs (fluconazole, Itraconazole, ketoconazole and amphotericin B, by dilution method (M27A2- CLSI). Yeasts were subjected PCR (polimerase chain reaction), RAPD (randomly amplified polymorphic DNA), and to RFLP (Restriction fragment lenght polymorphic), this last one, used for identification of Candida dubliniensis. Results: Considering the prevalent species, C. albicans showed high rates of significant sensitivity to azoles and the vast majority of produced virulence factors, regardless of their origin, infection or colonization. Statistical analysis enabled identification of 17 clusters with identical genetic identity, and other moderately related, or unrelated. Conclusions: There was no correlation between the genetic patterns with virulence and antimicrobial susceptibility for all isolates, suggesting that, the amplified genetic regions do not match with variables and might be related to other biological events. The inclusion of other primers could allow higher association among C. albicans strains. / Candida albicans é amplamente reconhecida como patógeno, ocorrendo freqüentemente em candidíase vulvovaginal. Objetivos. Comparar os genótipos entre os isolados de infecção, colonização e isolados recorrentes com os determinantes de virulência (fosfolipase, proteinase, amilase, gelatinase, hemolisina, termotolerância e biofilme) e susceptibilidade antifúngica in vitro. Material e Método. 313 amostras de fluido vaginal foram coletadas de mulheres com ou sem indicações sintomáticas para candidíase vulvovaginal (CVV), como prurido vaginal, corrimento, ardência e dispareunia. A susceptibilidade antimicrobiana foi avaliada frente a quatro drogas (fluconazol, itraconazol, cetoconazol e anfotericina B), determinada pelo método de diluição (M27A2-CLSI). As leveduras foram submetidas ao PCR (polimerase chain reaction), RAPD (randomly amplified polymorphic DNA), e ao RFLP (Restriction fragment lenght polymorphic), este último, utilizada para a identificação de Candida dubliniensis. Resultados. Considerandose a espécie prevalente, C. albicans mostrou taxas elevadas de sensibilidade significativos aos azólicos e, a grande maioria, produziu vários fatores de virulência, independente de sua origem, infecção ou colonização. A análise estatística permitiu a identificação de 17 clusters com identidade genética idêntica, e outros moderadamente relacionados, ou independentes. Conclusão. Não houve correlação entre os padrões genéticos com a virulência e susceptibilidade antimicrobiana, sugerindo que as regiões genéticas amplificadas estão relacionadas a outros eventos biológicos; a inclusão de outros primers poderá permitir uma associação maior entre os isolados de C. albicans.
5

Molecular Identification And Typing Of Lactobacillus Delbrueckii Subspecies Bulgaricus And Streptococcus Thermophilus

Cebeci Aydin, Aysun 01 February 2008 (has links) (PDF)
Lactic acid bacteria are associated with preservation of foods, including milk, meat and vegetables. Yoghurt is produced by the cooperative action of two starter bacteria / S. thermophilus and L. delbrueckii subsp. bulgaricus. In this study, identification and typing of yoghurt starter bacteria were aimed. Traditional home made yoghurts were collected from different areas of Turkey, identification of those isolates at species and subspecies level and typing at strain level were achieved using PCR based methods. In our study, identification of yogurt starter bacteria was studied using species specific primers and ARDRA. These methods were inefficient in identification of yoghurt starter bacteria, at species and subspecies level. Consequently, a reliable and quick method for accurate identification of yoghurt starter bacteria was developed. The new method focuses on amplification of methionine biosynthesis genes, for selective identification of yoghurt starter bacteria together with some cheese starters. Further discrimination by ARDRA enabled differentiation of yoghurt starter bacteria from cheese starters. Confirmation of the proposed method has been accomplished by partial sequencing of the 16S rRNA gene. After correct identification of starter bacteria had been achieved, the strains were typed at strain level using RAPD-PCR and MLST. RAPD-PCR with primer 1254 resulted better fingerprints, compared to primer M13 at strain level. Comparisons of the two typing methods showed that RAPD-PCR revealed strain diversity better than MLST, however MLST was a more robust and reliable method and resulted in clustering of the strains depending on the isolation source.
6

Identification Of Serotype Specific Dna Marker For Salmonella Typhimurium By Rapd-pcr Method

Aksoy, Ceren 01 September 2004 (has links) (PDF)
This study was performed for the identification of specific DNA marker using RAPD-PCR (Random Amplified Polymorphic DNA) method for serotype Salmonella Typhimurium which is one of the most prevalent serotype causing food poisining all over the world. The Primer 3 (RAPD 9.1), 5&rsquo / -CGT GCA CGC-3&lsquo / , was used in RAPD-PCR with 35 different Salmonella isolates. 12 of them were serotype Salmonella Typhimurium and 23 of them were belonging to other six different serotypes. Accordingly, two different 300 bp and 700 bp sized amplification products were obtained from the 12 different Salmonella Typhimurium isolates. On the other hand, other 23 Salmonella isolates of six different serotypes gave only 300 bp amplification band while 700 bp amplification band was not observed with Primer 3 (RAPD 9.1). After the discovery of 700 bp fragmentwhich was specific for S. Typhimurium, it was decided to sequence. The 700 bp band was ligated onto the vector pUC 19 to sequence. The cloninig operation gave positive results by the formation of blue and white colonies, but plasmid isolation process from white colonies containing the ligated vector was not achieved. Therefore, sequencing of the 700 bp fragment together with plasmid DNA could not be completed. However it wil be sent to USA for sequencing. According to these results, it was discovered that 700 bp amplification product was found as a specific polymorphic region for Salmonella Typhimurium after RAPD application on genomic DNA and this band can be used as a specific marker for detection and identification of Salmonella Typhimurium.
7

Molecular identification and quantification of the Penicillium roqueforti group /

Esberg Boysen, Marianne, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
8

Caracterização da diversidade genética de ovinos no Brasil com quatro técnicas moleculares / Genetic characterization of Brazilian sheep breeds by means of four molecular techniques

Paiva, Samuel Rezende 14 December 2005 (has links)
Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-06-06T11:18:38Z No. of bitstreams: 1 texto completo.pdf: 909512 bytes, checksum: 95d360795ba1a42ae10b3949c99caca0 (MD5) / Made available in DSpace on 2017-06-06T11:18:38Z (GMT). No. of bitstreams: 1 texto completo.pdf: 909512 bytes, checksum: 95d360795ba1a42ae10b3949c99caca0 (MD5) Previous issue date: 2005-12-14 / Fundação de Amparo a Pesquisa do Estado de Minas Gerais / Os ovinos foram introduzidos no Brasil principalmente pelos portugueses e espanhóis durante o processo de colonização. Por motivos sócio-culturais, a criação desses animais foi considerada no Brasil uma atividade de categoria inferior, de modo que foram criados somente para subsistência. Esse descaso fez com que os produtos derivados de ovinos (lã, carne, pele) perdessem competitividade frente aos produtores de outros países. Para que ocorra uma mudança desse cenário, é necessária uma profunda modificação logística de todas as classes envolvidas na produção de ovinos, visto que os ovinos representam, principalmente nas regiões Sul e Nordeste, uma fonte de recursos importante do ponto de vista social, cultural e histórico. O objetivo desse trabalho foi realizar um conjunto de técnicas moleculares que permitam a caracterização genética das principais raças e/ou estoques de ovinos naturalizados do Brasil de modo a.oferecer subsídios para a elaboração de programas estratégicos de conservação e melhoramento desta espécie. Foram utilizadas quatro classes de marcadores moleculares (RAPD, microssatélites, sequenciamento do DNA mitocondrial e do cromossomo Y) em até 11 raças de ovinos naturalizadas e comerciais existentes no Brasil. Os resultados permitiram identificar padrões de estruturação genética existentes nessa espécie no Brasil, bem como demonstraram a viabilidade de aplicação de marcadores moleculares para: 1) monitoramento genético de rebanhos; 2) testes de exclusão de paternidade para controle de pedigrees; 3) origem geográfica de raças ou populações; 4) inferências filogenéticas intra- específicas. / In Brazil, sheep breeds were introduced during the colonization process by Spanish and Portuguese settlers. Social and cultural factors determined that sheep rearing was considered a low-status activity, and therefore, sheep were raised only to meet subsistence goals. The outcome of this is that products derived from sheep such as wool, meat and hides are non competitive in the international market. A change of this scenario requires a profound logistic alteration involving all sheep production-related groups, particularly in the northern and southern regions in the country, where sheep are of high cultural, social and historical relevance. The objective of this work was to characterize the main naturalized Brazilian sheep breeds using molecular markers. Our results will be a baseline for the development of management and conservation programs. Four kinds of molecular markers were used (RAPD, microsatellites, and sequences of mtDNA and Y chromosome) and were applied on 11 breeds of naturalized and commercial breeds. Results identified the genetic structure of the species in the Country and demonstrated the efficiency of molecular markers for 1) herd genetic monitoring, 2) paternity (exclusion) analyses, 3) for determining the geographic origin of breeds and populations, and 4) for investigating within-species phylogenies.
9

Combined Roles of Glandular-haired Alfalfa and Natural Enemies in Alfalfa Pest Managment in Virginia

Dellinger, Theresa Ann 16 October 2003 (has links)
Both alfalfa weevil, <i>Hypera postica</i> (Gyllenhal), (Coleoptera: Curculionidae), and potato leafhopper, <i>Empoasca fabae</i> (Harris), (Homoptera: Cicadellidae), remain key pests of alfalfa in Virginia. Commercial varieties of potato leafhopper-resistant (or glandular-haired) alfalfa were released in the mid-1990s, but the impact of alfalfa weevil on these varieties has not been well documented. In 1999, two large-scale field experiments were initiated to compare the performance of a glandular-haired alfalfa variety against a standard, non-glandular-haired variety under both alfalfa weevil and potato leafhopper pest pressures in the southwestern and Piedmont regions of Virginia over a 3 year period. Results indicated that alfalfa weevil must be managed in potato leafhopper-resistant alfalfa to limit crop loss. Surprisingly, similar densities of potato leafhoppers were found in both the glandular-haired and standard varieties. Both varieties frequently had similar yields and forage quality. In general, the glandular-haired variety did not outperform the standard variety. Results also indicated that insecticide application did not always provide the expected benefits of higher yields and forage quality, despite reducing pest densities for 2-3 weeks after application. These data suggest that the economic thresholds for one or both of these pests in Virginia may require adjustment. The potential impact of glandular-haired alfalfa on the natural enemies of alfalfa weevil was examined as well. <i>Bathyplectes anurus</i> (Thompson) (Hymenoptera: Ichneumonidae) was the dominant parasitoid attacking weevil larvae at both locations. Parasitization of weevil larvae by <i>Bathyplectes</i> spp. did not appear to be adversely affected by the presence of glandular trichomes on the potato leafhopper-resistant variety. Glandular trichomes had little impact on the infection of weevil larvae by the fungus <i>Zoophthora phytonomi</i> as well, but this was not unexpected. The genetic variation of <i>B. anurus</i> was surveyed at both study sites using RAPD-PCR to establish or eliminate the possibility that differences in parasitization levels between the Piedmont and southwestern regions could be attributed to the presence of different parasitoid strains. Most of the detected phenotypic variation was attributed to within population variation, with very little variation occurring between the two populations. However, the between population variation was statistically significant in 2000, but not in 2001. / Ph. D.
10

Polyarthra-Rotatorien - zyklomorphe Generationen oder ein Komplex zahlreicher Arten" Elektronenmikroskopische und DNA-analytische Untersuchungen

Leutbecher, Christine 17 March 2005 (has links)
Polyarthra-Rotatorien - zyklomorphe Generationen oder ein Komplex zahlreicher Arten? Elektronenmikroskopische und DNA-analytische Untersuchungen In der vorliegenden Arbeit wurde die Gattung Polyarthra (Rotatoria: Monogononta) taxonomisch untersucht. Dazu wurden licht- und rasterelektronenmikroskopische Untersuchungen sowie DNA-Analysen (RAPD-PCR) durchgeführt. Von den bisher 10 als valid geltenden Arten konnten Individuen von sieben Arten (P. euryptera, P. remata, P. major, P. dolichoptera, P. longiremis, P. vulgaris, P. luminosa) gesammelt und untersucht werden. Außerdem wurden Morphen bearbeitet, die Merkmale von verschiedenen Arten zeigten und keiner Art eindeutig zugeordnet werden konnten. Insgesamt wurden 31 verschiedene Polyarthra-Populationen aus 11 unterschiedlichen Gewässern untersucht. Ein Ziel der Arbeit bestand darin festzustellen, ob die unterschiedlichen Polyarthra-Morphen zyklomorphe einer bzw. weniger (bekannter) Arten sind oder ob sie mehrere distinkte Arten darstellen. Der Schwerpunkt der morphologischen Untersuchungen bezog sich auf den Trophus (Kauer), der bei Monogononten als artcharakteristisch gilt. Zeichnungen vom Habitus und/oder Trophus mehrerer verschiedener Morphen wurden als Originale oder aus der Literatur zusammengetragen, um einen umfangreichen Vergleich zu ermöglichen. Die DNA für die RAPD-PCR-Analysen wurde aus Einzelindividuen gewonnen, wobei die Optimierung der DNA-Isolierung im Vorfeld eigens dafür entwickelt wurde. Drei Random Primer pro Individuum konnten so angewendet werden. Sowohl morphologische als auch RAPD-Daten wurden Cluster-Analysen in Form von Parsimonie-Berechnungen unterzogen. Die RAPD-Daten wurden zusätzlich mit phänetischen Methoden berechnet. Die morphologischen und DNA-analytischen Daten lieferten danach folgende Ergebnisse: Das Auftreten von Zyklomorphose innerhalb der Polyarthren scheint eher selten zu sein. Die Validität der Arten P. euryptera, P. luminosa, P. major und P. remata konnte bestätigt werden. Nicht zweifelsfrei konnte P. vulgaris nachgewiesen werden. In Frage gestellt wird die Validität von P. dolichoptera und P. longiremis.

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