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Identifizerung von Candia-Spezies und -Stämmen durch den Nachweis von polymorphen DNA-Regionen in der PCRAndrade, Manuel 12 July 1999 (has links)
Für die Identifizierung bzw. Differenzierung von Candida- Spezies und -Stämmen sowie für die Bestimmung der genetischen und epidemiologischen Verwandtschaft von Stämmen der gleichen Spezies wurde eine PCR-Fingerprint-Technik und eine RFLP-Analyse der amplifizierten ITS-Region angewandt. Das PCR-Fingerprinting amplifiziert anonyme Sequenzen in der chromosomalen DNA, die über das gesamte Genom verteilt sind. Die ITS-Region ist Bestandteil des ribosomalen Operons, welches in ca. 50-100 Kopien/Zelle vorhanden ist. 1.a. Beide molekularbiologischen Verfahren wurden zur Unterscheidung von routinemäßig schwer differenzierbaren klinischen Candida famata und Candida guilliermondii-Isolaten genutzt. Von insgesamt 37 fraglichen Stämmen konnten 31 als C. guilliermondii und 3 als C. famata identifiziert werden, die drei verbliebenen Stämme waren mit diesen Techniken nicht identifizierbar. Mit der Biochemotypie gelang nur die Zuordnung eines der 3 C. famata-Isolate sowie von 23 der 31 C. guilliermondii-Isolate. 14 Isolate wurden mit den konventionellen Methoden gar nicht oder falsch identifiziert. 1b. Mit dem PCR-Fingerprinting wurde auch die Spezieszugehörigkeit phänotypisch veränderter Candida albicans-Isolate überprüft. Alle atypischen Stämme, bei denen solche für C.albicans charakteristischen Merkmale wie die Bildung von Chlamydosporen, die Verwertung der Aminozucker Glukosamin und N-Acetylglukosamin sowie die Assimilation von 2-Ketogluconat und Xylose nicht ausgeprägt waren, wiesen die für C. albicans typischen Fingerprintmuster auf. Unsere Studie zeigte, daß die biochemische Typisierung an Grenzen stößt, wenn typische Stoffwechselreaktionen nicht nachgewiesen werden können. 2. Bei 6 verschiedenen C. albicans-Populationen aus Angola, Madagaskar, Deutschland und Portugal wurde die Variabilität phänotypischer und genotypischer Merkmale untersucht, wobei in diese Analyse auch atypische Stämme miteinbezogen wurden. Während die phänotypischen Eigenschaften, bis auf die der atypischen Stämme, kaum variierten, wurden für die insgesamt 212 C. albicans-Isolate 87 unterschiedliche PCR-Fingerprint-Genotypen nachgewiesen. Eine Analyse der Beziehungen zwischen den Fingerprint-Genotypen wurde mit der UPGMA-Distanz-Methode durchgeführt. 3. Weiterhin wurden Candida-Vaginalisolate von Patientinnen mit rezidivierenden Episoden von Candida-Vaginitis mit Stämmen verglichen, die aus anderen Körperregionen stammten bzw. bei ihren Partnern isoliert wurden. Es konnte gezeigt werden, daß Stammaustausche zwischen den Partnern vorkommen, ein Stamm ohne oder mit geringfügigen genotypischen Veränderungen trotz Therapie persistieren kann und daß eine Reinfektion auch durch einen neuen Stamm möglich ist. Das Problem der Erregeridentifizierung in der mykologischen Labordiagnostik ist sowohl klinisch als auch epidemiologisch relevant. Molekularbiologische Methoden sollen gut funktionierende konventionelle Methoden zur Erregeridentifizierung nicht ersetzen, können aber bei Problemfällen eine wertvolle Ergänzung für die mykologische Diagnostik vorzugsweise in fachständigen Referenzlaboratorien darstellen. / A PCR fingerprinting approach and a RFLP analysis of the amplified ITS region were used to differentiate Candida species and strains as well as to assess genetic and epidemiological relationships of strains belonging to the same species. The PCR fingerprinting amplifies anonymous DNA sequences sampled throughout the whole genome. The ITS region is part of the ribosomal operon which occurs in tandem arrays of nearly 50-100 copies in one cell. 1.a. Both methods were used to identify clinical isolates of C. famata and C. guilliermondii which were difficult to differentiate with routine methods. Out of 37 ambiguous isolates 31 could be identified as C. guilliermondii, 3 as C. famata and the other 3 were not identifiable. Biochemical typing (Api 32 C V.1) identified only 23 out of 31 C. guilliermondii and 1 out of 3 C. famata whereas 14 isolates were misidentified or not identified at all. 1.b. By using the PCR fingerprinting technique strains of C. albicans with altered phenotypes could be identified at species level. Atypical isolates which did not express those characteristics which are thought to be typical for C.albicans like the formation of clamydospores, the ability to metabolise the amino sugars glucosamine and N-acetylglucosamine as the sole carbon source or to assimilate 2-ketogluconate and xylose showed the PCR patterns typical for C.albicans. Our study revealed that biochemical and morphological methods of species identification are limited if some of the key reactions fail. 2. We investigated the variability of phenotypic and genotypic properties of 6 different C. albicans populations from different countries (Angola, Madagascar, Portugal and Germany) including atypical strains. Except for the atypical strains only very little phenotypical variation was observed. However, 87 different genotypes were found among the 212 strains. The relatedness of the fingerprint-genotypes were analysed by measuring genetic distances with the UPGMA method. 3. Vaginal isolates of Candida spp. obtained from patients with recurrent episodes of vaginitis were compared with isolates from different body locations of the women and from their male partners. It has been shown that strain exchanges between the partners occur, that the original strain with or without minor genotypic changes can persist despite of the therapy, but also that reinfection by a new strain is possible. The identification of an ethiological agent by the mycological diagnostic laboratory is of clinical and epidemiological importance. Molecular biological methods should not replace well established conventional methods but they can supplement the identification of fungal pathogens in specialised reference laboratories if diagnosis cannot be achieved easily by conventional diagnostic procedures.
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Mapeamento de QTLs para resistência a grãos ardidos causados por diplodia (Stenocarpella Sp.) em milho (Zea Mays L.)Gutiérrez, Humberto Ignácio 28 February 2008 (has links)
Diplodia ear rot caused by the fungus Stenocarpella maydis (Berkeley) and Stenocarpella
macrospora (Earle) have become one of the most important limiting factors for the production
of Corn (Zea mays L.) in Brazil. The fungus can attack the stalks, leaves and the grain
causing significant reductions on yield and the overall quality of the grain, since it can produce
micotoxinas that are dangerous to livestock. Resistance to ear rot by Stenocarpella sp in corn
is quantitative and highly influenced by the environment and even that artificial inoculation
techniques are available to screen for the disease the overall cost is very expensive. The
objective of this study was the identification of quantitative trait loci (QTL s) associated with
ear rot resistance by Stenocarpella sp in one breeding population composed of 141 doublehaploid
progenies resulted from the cross among the resistant inbred MONDR1 and the
susceptible inbred MONDS1 in testcrosses with the susceptible tester MONDS5. Testcrosses
were evaluated at harvest time after artificial inoculation for ear rot at three different locations
in the central region of Brazil during the 2005/06 summer season. Thru Composite interval
mapping (CIM), a total of three QTL s (LOD>2.5) for ear rot resistance were identified at
chromosomes 2, 3 and 5, all together accounting for up 26% of total phenotypic variation for
this character. The identification of two QTL s for ear rot resistance coming from the
susceptible parent MONDS1 appear to indicate the presence of the phenomena of
transgressive segregation. Additionally we were able to identify six double-haploid progenies
with high level of resistance to ear rot by Stenocarpella (MDH15, MDH443, MDH95, MDH2,
MDH120 e MDH81), being those recommended for their incorporation into the breeding
program as new breeding sources for the Central Brazil regions. / Grãos ardidos causados pelos fungos Stenocarpella maydis (Berkeley) e Stenocarpella
macrospora (Earle) tem se constituído num dos maiores fatores limitantes para a produção de
milho (Zea mays L.) no Brasil. Estes fungos podem causar infecções no colmo, folhas e grãos,
podendo ocasionar reduções significativas na produtividade e na qualidade do grão, pela
produção de micotoxinas daninhas para aves e bovinos. A resistência para podridão de grão
por Stenocarpella sp apresenta herança quantitativa e pode ser altamente influenciada pelo
meio ambiente, e embora existam técnicas de inoculação que facilitam a discriminação de
materiais suscetíveis, isto requer de grande quantidade de recursos. O objetivo do presente
trabalho foi à identificação de locos de caracteres quantitativos (QTL) associados à resistência
para podridão de grãos ( grãos ardidos ) ocasionados por Stenocarpella sp numa população de
141 progênies duplo-haplóides derivadas do cruzamento entre a linhagem resistente MONDR1
e a linhagem susceptível MONDS1 em testcross com o testador susceptível MONDS5. A
porcentagem de espigas infectadas por Stenocarpella sp foi registrada para cada uma das
testcrosses apos da inoculação artificial em três localidades na região Central de Brasil
durante a Safra agrícola 2005/06. Mediante a análise de mapeamento por intervalo composto
foram identificados três QTL s com LOD>2.5 para resistência à grãos ardidos nos
cromossomos 2, 3 e 5, sendo estes em conjunto, responsáveis por ate 26% de variação
fenotípica para este caráter. A identificação de dois QTL s para resistência a grãos ardidos por
Stenocarpella sp com origem no progenitor susceptível parece indicar a presença do fenômeno
de segregação transgressiva. Adicionalmente foram identificadas seis progênies duplohaplóides
com alto nível de resistência a grãos ardidos (MDH15, MDH443, MDH95, MDH2,
MDH120 e MDH81), sendo estas recomendadas para sua incorporação no programa de
melhoramento para a região central do Brasil. / Mestre em Genética e Bioquímica
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Genový polymorfismus Th1/Th2 cytokinů u pacientek s děložní myomatózou / Th1/Th2 cytokine gene polymorphisms in patients with urine fibroidSosna, Ondřej January 2011 (has links)
Background: Uterine fibriod (UF) or leiomyoma is the most frequent benign tumour upon lower genital tract and represents the most frequent indication for hysterectomy. The aetiology remains still unknown. The genetic factors contributing for the development of UF are being intensively investigated. The aim of our study was to look for possible genetic markers which could be used as prognostic tools for evaluation of an increased risk for development of UF. Methods: The study group enrolled 102 patients diagnosed with UF and 145 healthy controls. Ultrasonographic examination of the pelvis was performed and a single blood sample was taken in all women. Histological verification followed the surgery in the patient group. The principal of the cytokine gene polymorphisms detection is based on PCR reaction with sequence-specific primers. Results: A large spectrum of Th1/Th2 cytokine gene polymorphisms in patients with uterine fibroid was compared with control group. The frequencies of the majority of tested cytokine gene SNP in the patient cohort were not statistically different from the cytokine SNP in the control group. However, an intriguing association between polymorphisms of the IL-4 gene promotor at positions -590 C/T and -33 C/T, and the risk of leiomyoma was observed. The CC genotype of IL-4 at position...
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Genový polymorfismus Th1/Th2 cytokinů u pacientek s děložní myomatózou / Th1/Th2 cytokine gene polymorphisms in patients with urine fibroidSosna, Ondřej January 2011 (has links)
Background: Uterine fibriod (UF) or leiomyoma is the most frequent benign tumour upon lower genital tract and represents the most frequent indication for hysterectomy. The aetiology remains still unknown. The genetic factors contributing for the development of UF are being intensively investigated. The aim of our study was to look for possible genetic markers which could be used as prognostic tools for evaluation of an increased risk for development of UF. Methods: The study group enrolled 102 patients diagnosed with UF and 145 healthy controls. Ultrasonographic examination of the pelvis was performed and a single blood sample was taken in all women. Histological verification followed the surgery in the patient group. The principal of the cytokine gene polymorphisms detection is based on PCR reaction with sequence-specific primers. Results: A large spectrum of Th1/Th2 cytokine gene polymorphisms in patients with uterine fibroid was compared with control group. The frequencies of the majority of tested cytokine gene SNP in the patient cohort were not statistically different from the cytokine SNP in the control group. However, an intriguing association between polymorphisms of the IL-4 gene promotor at positions -590 C/T and -33 C/T, and the risk of leiomyoma was observed. The CC genotype of IL-4 at position...
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Performance-Aware Code Size Optimization of Generic Functions through Automatic Implementation of Dynamic Dispatch / Prestandamedveten kodstorleksoptimering av generiska funktioner genom automatisk tillämpning av dynamic dispatchHärnqvist, Ivar January 2022 (has links)
Monomorphization and dynamic dispatch are two common techniques for implementing polymorphism in statically typed programming languages. Function templates in C++ use the former technique to enable algorithms written as generic functions to be efficiently reused with multiple different data types by producing a separate function instantiation for each invocation that uses a unique permutation of argument types. This avoids the overhead of indirection associated with dynamic dispatch and allows the generated code of each instantiation to be optimized by the compiler for its specific concrete types, which typically yields great improvements in runtime performance over any dynamic approach. The disadvantage of this implementation, compared to the type-erased generics found in many other programming languages, is that careless over-use of templates with many different argument types can lead to an excessive amount of redundant code being generated for the same function. This increase in code size may increase the binary size of the final program and reduce the amount of useful code that can fit into the processor's instruction cache during execution, reducing code locality and thereby potentially reducing performance. Monomorphization can also increase compilation time due to the increase in generated code that needs to be compiled and optimized. This thesis presents a heuristic-based approach to generic programming that allows function templates to be automatically converted to use dynamic dispatch in scenarios where the resulting negative impact on runtime performance is predicted to be low. The thesis project includes the development of a proof of concept plugin for the Clang compiler frontend that can be used to compile existing C++ projects with the conversions applied. The design of a heuristic function for determining whether a given function template should use monomorphization or dynamic dispatch based on statically known metrics is proposed based on the results of an experiment. This heuristic is shown to achieve a small general improvement in program size across a set of open-source C++ projects when they are compiled using the plugin. The key findings from the experiment and from the development of the plugin are summarized with a general strategy for how the approach can be integrated into the design of future programming languages to promote more extensive use of generic programming in performance-sensitive code while avoiding regressions in program size and compilation time.
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