La tuberculosis es una enfermedad infecciosa que constituye un grave problema de salud pública a nivel mundial principalmente en países en vías de desarrollo, como el Perú. Las limitaciones de los métodos clásicos de diagnostico (baciloscopía y cultivo) así como la alta frecuencia de ésta enfermedad han creado la necesidad de implementar nuevas estrategias para incrementar la sensibilidad de las pruebas y a su vez reducir el tiempo necesario para establecer el diagnostico confirmatorio. Considerando que los estudios correspondientes a la región del Tracto Respiratorio Inferior (TRI) son escasos, el objetivo de esta tesis fue determinar el perfil molecular de Mycobacterium tuberculosis en muestras biológicas del TRI de pacientes limeños con sospecha de tuberculosis. En el presente trabajo se evaluaron 43 muestras de pacientes limeños con sospecha clínica de tuberculosis las cuales fueron obtenidas a través de lavado bronquial, aspirado bronquial, secreción bronquial, lavado bronco-alveolar, aspirado bronco-alveolar y broncofibroscopía. De estas muestras se extrajo DNA y se realizó la prueba del PCR - Nested, para ello se empleó como secuencia diana el gen de la proteína A (65KDa) de Mycobacterium tuberculosis, los productos amplificados fueron evidenciados mediante electroforesis en gel de agarosa y tinción con bromuro de etidio. Los resultados obtenidos muestran que el 77% de las muestras procesadas poseen DNA de Mycobacterium tuberculosis, demostrándose la alta sensibilidad y especificidad del método empleado, el 82% de estas muestras correspondieron a la región del árbol bronquial superior, debido a que esta región es el punto de partida para la diseminación de esta micobacteria hacia otras regiones del tracto respiratorio y además, a que la mayoría de muestras fueron tomadas directamente de esta región. Asimismo, la aplicación de la prueba PCR- Nested incrementó la sensibilidad de detección 5.5 veces con respecto a un único evento de amplificación, lo cual demuestra la utilidad de esta prueba en el análisis de material biológico con baja carga micobacteriana como las empleadas en este trabajo. Finalmente, se concluye que la prueba PCR- Nested es un método altamente sensible y específico para detectar DNA de Mycobacterium tuberculosis a partir de muestras procedentes del TRI. / Tuberculosis is an infectious disease that constitutes a serious public health problem worldwide, mainly in developing countries such as Peru. The limitations of the traditional methods of diagnosis (smear and culture) as well as the high incidence of this disease have created the need to implement new strategies to increase the sensitivity of tests to reduce time to establish a confirmed diagnosis. Since there are not many researches at the region of the Lower Respiratory Tract (LRT), the objective of this study was to determine the molecular profile of Mycobacterium tuberculosis in biological samples taken from the LRT of patients with suspicion tuberculosis. In the present study, 43 samples from patients with clinical suspicion of tuberculosis were evaluated. The samples were obtained through bronchial lavage, bronchial aspirate, bronchial secretions, bronco-alveolar lavage, and sucked bronco-alveolar broncofibroscopy. DNA extraction was prepared from each sample, and it was used in a PCR- Nested test targeting the gene encoding the protein A (65KDa) from M. tuberculosis. The results showed that DNA from M. tuberculosis was detected in 77% of the processed samples, revealing a high sensitivity and specificity of this method. From the positive samples, 82% corresponded to those obtained from the bronchial tree top region. This last result is explained because of the fact that most of the samples were taken directly from this region, which is the starting point for the mycobacteria dissemination toward other regions of the respiratory tract. In addition, the application of the PCR-Nested test increased the sensitivity of detection by 5.5 fold compared to a single event amplification, demonstrating the usefulness of this test in the analysis of biological material with low mycobacterial load as those used in this work. Finally, we conclude that the PCR-Nested test is a highly sensitive and specific method for detecting DNA from Mycobacterium tuberculosis in samples from the LRT.

Thesis (M.Med.Sc.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 39-49).

Thesis (Ph.D.)--Aberdeen University, 2009. / Title from web page (viewed on July 8, 2009). Includes bibliographical references.

Thesis (Ph. D.)--Virginia Commonwealth University, 2006. / Prepared for: Dept. of Chemistry . Bibliography: leaves 102 - 109. Also available online.

The role of the transposable insertion sequence IS<i>6110 </i>was studied in the evolution of <i>Mycobacterium tuberculosis </i>in 202 isolates from 40 countries. The isolates were analyzed by IS<i>6110 </i>insertion site mapping, spoligotyping, IS<i>6110 </i>RFLP fingerprints and <i>in silico </i>comparisons. Different IS<i>6110 </i>insertion sites exhibited a wide range of variation in the presence or absence of IS<i>6110 </i>in isolates varying between sites with only one isolate identified with the insertion, singletons, to sites where many isolates harboured an IS<i>6110 </i>insertion, common insertions.  95% of isolates were split into ten IS<i>6110 </i>cluster groups or lineages (ICG-1 to 8, ICG-a and ICG-b) based on their common IS<i>6110</i> insertion site patterns.  No <i>M. tuberculosis </i>isolates were found which were intermediate between ICG cluster groups.  A non-random association of IS<i>6110 </i>alleles over loci and also a high correlation between the common IS<i>6110 </i>cluster groups and spoligotype families suggested that common IS<i>6110 </i>insertions are predominantly the result of unique evolutionary event polymorphisms and they are therefore robust and valuable markers for phylogenetic and evolutionary studies of <i>M. tuberculosis.</i> 14 IS<i>6110-</i>assocaited deletions, including nine new regions of deletion were detected in the studied isolates.  Phylogenetic analysis of these genomic deletions demonstrated that they can also be used to classify the majority of MTB lineages including ICG-1/Beijing, ICG-3/CAS, ICG-5/a part of T, ICG-4/S and a major part of the ICG-6/LAM lineage. Published literature and DNA sequence databases were used to establish a global IS<i>6110 </i>database comprising of 524 different IS<i>6110</i> insertion sites across the genome and this database was used to study the role of IS<i>6110</i> in the fitness of <i>M. tuberculosis.  </i>The distribution of these sites showed a significant bias into intergenic regions, non-essential genes, multi-copy genes, other insertion elements and genomic repeat regions.  Common IS<i>6110</i> insertions may well have played an important role in the evolution of <i>M. tuberculosis.</i>

Thesis (M.S.)--Case Western Reserve University, 2007. / [School of Medicine] Department of Pathology. Includes bibliographical references.

Se caracterizaron los genotipos de cepas de M. tuberculosis resistente, multidrogorresistente (MDR), MDR asociada a resistencia a drogas de segunda línea (MDR plus) y sensible a las drogas que proceden de los distritos de Lima y Callao. Cuarenta y nueve pacientes con TB fueron incluidos en el estudio. Los genotipos de M. tuberculosis fueron establecidos por PCR usando el primer Mtb2 (5’-CGG-CGG-CAA-CGG-CGG-CA-3’) en combinación con primers situados inversamente en los flancos repetitivos de la IS6110. Se revisaron las historias clínicas de los pacientes para la obtención de información epidemiológica. La susceptibilidad a isoniacida, rifampicina, estreptomicina, etambutol, kanamicina, acido p-amin-salicilico, tioacetazona y pirazinamida fueron estudiados. / We characterise the genotypes of Mycobacterium tuberculosis both resistant, multidrug resistant (MDR), multidrug drug resistant plus (MDR plus) and susceptible to drugs strains come from to Lima and Callao. Forty-nine patients with TB were included in the study. The genotypes of the M. tuberculosis isolates were established by PCR using the primer Mtb2 (5’-CGG-CGG-CAA-CGG-CGG-CA-3’) in combination with primers sited at inverted repeats flanking IS6110. Were revised the clinical history of the patients for epidemiological information. The susceptibility to isoniacid, rifampicin, streptomycin, ethambutol, kanamycin, para-amin-salicylic acid, tioacetazon and pyrazinamide was studied.

Thesis (Ph. D.)--University of Alberta, 2009. / Title from pdf file main screen (viewed on Nov. 25, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Chemistry, University of Alberta." Includes bibliographical references.

Diss. (sammanfattning) Stockholm : Karol inst., 2004. / Härtill 5 uppsatser.

Thesis (M.S.)--Florida State University, 2006. / Advisor: Timothy M. Logan, Florida State University, College of Arts and Science, Dept. of Chemistry and Biochemistry. Title and description from dissertation home page (viewed Sept. 15, 2006). Document formatted into pages; contains xi, 63 pages. Includes bibliographical references.