Publicación a texto completo no autorizada por el autor / Determina los genotipos y la sensibilidad a los antifúngicos de cepas de Cryptococcus neoformans, provenientes de aislamientos clínicos y ambientales efectuados en la ciudad de Lima. El estudio es descriptivo. La población de microorganismos está constituida por cepas de Cryptococcus neoformans provenientes de aislamientos clínicos y ambientales. Para determinar el genotipo se utiliza la técnica del análisis del polimorfismo en longitud de fragmentos amplificados (AFLP), según instrucciones del fabricante. Para determinar la sensibilidad se utiliza un panel de 3 compuestos antifúngicos: anfotericina B, fluconazol y voriconazol. Mediante la técnica del AFLP, se determina que el 50% de las cepas son del genotipo AFLP1 (16) y el 40,6% del genotipo AFLP1B (13), ambos correspondieron a C. neoformans var. grubii; asimismo, el 6,3% resulta ser del genotipo AFLP2 (2) (C. neoformans var. neoformans) y el 3,1% es del genotipo AFLP3 (1), es decir, un híbrido entre las dos variedades de C. neoformans. Los perfiles de sensibilidad antifúngica para la anfotericina B, fluconazol y voriconazol indicaron que las 32 cepas de C. neoformans son sensibles a los 3 compuestos antifúngicos. Se observa que C. neoformans var. grubii (AFLP1 y AFLP1B) y C. neoformans var. neoformans (AFLP2) son las únicas variedades de Cryptococcus implicadas en infecciones en humanos. Asimismo, se demuestra que todas las cepas son sensibles a los antifúngicos probados, de acuerdo a lo reportado en la literatura internacional. / Tesis

Relapsing fever (RF) is a disease caused by tick- or louse-transmitted bacteria of the genus Borrelia. It occurs worldwide but is most common in Africa where it is one of the most prevalent bacterial diseases. The main manifestation is a recurring fever which coincides with massive numbers of bacteria in the blood. Severity ranges from asymptomatic to fatal. RF is usually considered a transient disease. In contrast, B. duttonii causes a persistent, residual brain infection in C57BL/6 mice which remains long time after the bacteria are cleared from the blood. The host gene expression pattern is indistinguishable from that of uninfected animals, indicating that persistent bacteria are not recognized by the immune system nor do they cause noticeable tissue damage. This is probably due to the quite low number of bacteria residing in the brain. The silent infection can be reactivated by immunosuppression allowing bacteria to re-enter the blood. To investigate if the residual infection is in a quiescent state or if the bacteria are actively dividing, mice with residual brain infection were treated with the cell-wall disrupting antibiotic ceftriaxone, which is only active against dividing bacteria. Since all mice were cured by ceftriaxone we conclude that the bacteria are actively growing in the brain rather than being in a latent, dormant state. The brain is used as an immunoprivileged site to escape host immune defence and probably as a reservoir for bacteria. RF is a common cause of pregnancy complications, miscarriage and neonatal death in sub-Saharan Africa. We established a murine model of gestational relapsing fever to study the pathological development of these complications. B. duttonii infection during pregnancy results in intrauterine growth retardation as well as placental damage and inflammation. Spirochetes cross the maternal-foetal barrier, resulting in congenital infection. Further, pregnancy has a protective effect, resulting in milder disease during pregnancy. A clinic-based study to investigate the presence of RF in Togo was performed. Blood from patients with fever were examined for RF by microscopy, GlpQ ELISA and PCR. About 10% of the patients were positive by PCR and 13% had antibodies to GlpQ. Many RF patients originally had a misdiagnosis of malaria, which resulted in ineffective treatment. The inability of microscopic analysis to detect spirochetes demonstrates the need for tests with greater sensitivity. To provide simple, fast, cheap and sensitive diagnostics using equipment available in small health centres, a method based on enrichment of bacteria by centrifugation and detection by Giemsa staining was developed which detects <10 spirochetes/ml. To study the phylogeny of RF, IGS and glpQ were sequenced and neighbor joining trees were constructed. B. persica and B. hispanica were distant from the other species iswhereas B. crocidurae appeared to be a heterogeneous species. B. duttonii is polyphyletic in relation to B. recurrentis suggesting that the two species may in fact be the same or have a polyphyletic origin.

Σκοπός. Η δραστηριότητα της β-γλυκουρονιδάσης στο εγκεφαλονωτιαίο υγρό (ΕΝΥ) είναι αυξημένη στην βακτηριακή μηνιγγίτιδα, αλλά η πορεία της κατά τη διάρκεια της θεραπείας είναι άγνωστη. Σκοπός της μελέτης ήταν η μέτρηση της δραστηριότητας της β-γλυκουρονιδάσης κατά τη διάρκεια της θεραπείας και η σύγκρισή της με άλλες κυτταρικές και βιοχημικές παραμέτρους του ΕΝΥ. Μέθοδος. H δραστηριότητα της β-γλυκουρονιδάσης, ο αριθμός κυττάρων, η συγκέντρωση πρωτεΐνης και ο λόγος γλυκόζης ΕΝΥ/αίματος μετρήθηκαν κατά τη διάρκεια της θεραπείας σε 47 ασθενείς με βακτηριακή μηνιγγίτιδα, από τους οποίους 4 ήταν νεογνά και 97 μάρτυρες. Οι ασθενείς υποβλήθηκαν σε 1 ή 2 επαναληπτικές οσφυονωτιαίες παρακεντήσεις. Επίσης η δραστηριότητα της β-γλυκουρονιδάσης μετρήθηκε σε 8 ασθενείς με πυελονεφρίτιδα και στείρα πλειοκυττάρωση ΕΝΥ. Αποτελέσματα. Πριν τη θεραπεία η διάμεση δραστηριότητα της β-γλυκουρονιδάσης σε ασθενείς βρεφικής μέχρι εφηβικής ηλικίας ήταν 136 moles 4-methylumbelliferone/ml/ώρα (με διακύμανση από 44 έως 826), ενώ στους μάρτυρες ήταν 14 nmoles/ml/ώρα (με διακύμανση 7 έως 23) (p<0,000001). Σε όλους τους ασθενείς με κλινική βελτίωση, η δραστηριότητα της β- γλυκουρονιδάσης ήταν χαμηλότερη σε δείγματα ΕΝΥ, τα οποία ελήφθησαν μετά πάροδο τουλάχιστον 6 ωρών από την έναρξη της θεραπείας. Έξι μέχρι 12 ώρες μετά την έναρξη της θεραπείας η διάμεση δραστηριότητα της β-γλυκουρονιδάσης είχε ήδη μειωθεί κατά 59%. Αντιθέτως, οι υπόλοιποι παράμετροι του ΕΝΥ έδειξαν μεταβλητότητα των τιμών τους, κατά τις πρώτες 24 ώρες της θεραπείας, η οποία ήταν ανεξάρτητη από την πορεία της νόσου. Σε 1 ασθενή με πνευμονιοκοκκική μηνιγγίτιδα, ο οποίος ενεμφάνισε επιδείνωση των συμπτωμάτων του 22 ώρες μετά την έναρξη της θεραπείας, η δραστηριότητα της β-γλυκουρονιδάσης αυξήθηκε κατά 89%. Στη νεογνική μηνιγγίτιδα η δραστηριότητα της β-γλυκουρονιδάσης πριν τη θεραπεία ήταν αυξημένη, αλλά η παρακολούθηση της πορείας της νόσου απαιτεί παρατεταμένη περίοδο ενζυμικών μετρήσεων, για έγκαιρη ρύθμιση της θεραπείας επί υποτροπών και αναμολύνσεων. Συμπεράσματα. Η δραστηριότητα της β-γλυκουρονιδάσης του ΕΝΥ είναι αξιόπιστος δείκτης βακτηριακής μηνιγγίτιδας, που μπορεί να προσδιορίσει, νωρίς στην πορεία της νόσου, την ανταπόκριση στην θεραπεία. / Aim: β-Glucuronidase activity is increased in the cerebrospinal fluid (CSF) of patients with bacterial meningitis. The aim of this study was to investigate the β-glucuronidase activity in the cell-free CSF of bacterial meningitis, its course during treatment and compare it to other CSF parameters. Methods: The β-glucuronidase activity, cell number, protein concentration and CSF/blood glucose ratio were measured in 47 consecutive infants and children with bacterial meningitis, and 97 control subjects. Patients had 1 or 2 follow-up lumbar punctures. Results: The β-glucuronidase activity was increased early in bacterial meningitis, even when the other CSF parameters were undisturbed. Before treatment, the median activity in affected children was 136 moles 4-methylumbelliferone/L/h (range 44-826) and in controls 14 (7-23). In all patients who improved, the activity was lower in the follow-up CSF samples. Six to 12 hours after starting treatment, the median activity was already reduced by 59%. The other CSF parameters showed a variability during the first 24 hours of treatment independently of the course of the disease. Multiple comparisons of the CSF parameters in 17 patients who had 2 follow-up punctures showed that the β-glucuronidase activity was the best prognostic index. Conclusion: β-Glucuronidase activity in the CSF is a reliable indicator of bacterial meningitis, which can identify the response to treatment early in the course of illness. The enzyme activity is increased early in the disease, even when the other laboratory parameters from the CSF remain normal.

Diss. (sammanfattning) Linköping : Linköpings universitet, 2005. / Härtill 4 uppsatser.

Thesis (M.C.T.M. (Clinical Tropical Medicine))--Mahidol University, 2003.

Ulm, Univ. Diss., 2006.

Thesis (D.P.H.)--University of Alabama at Birmingham, 2010. / Title from PDF title page (viewed on July 1, 2010). Includes bibliographical references.

Membros da família Enterobacteriaceae podem causar meningite associada com infecções hospitalares e/ou secundárias. A terapia empírica utilizada em pacientes com suspeita de meningite é, às vezes, ineficiente, devido à produção de beta-lactamases de espectro estendido (ESBL), que é o mecanismo mais comum de resistência às cefalosporinas de amplo espectro em enterobactérias. O objetivo deste trabalho foi estudar a produção de ESBL e AmpC por enterobactérias isoladas de líquido céfalo-raquidiano e sangue de pacientes com suspeita de meningite da região de Ribeirão Preto, no período de 2000 a 2005. O teste do disco combinado foi utilizado para a detecção fenotípica e a PCR foi utilizada para amplificar genes codificadores de ESBL e AmpC. Três (6,52 %) das 46 enterobactérias isoladas no período estudado foram produtoras de ESBL e abrigavam o gene blaCTX-M-2. As enterobactérias produtoras de ESBL foram: S. marcescens IAL 19, (isolada em Araraquara, 2002), P. mirabilis IAL 29 e E. coli IAL 45 (isoladas em Franca, respectivamente, 2003 e 2004). O gene blaCTX-M-2 foi detectado em três gêneros diferentes, sugerindo que o gene blaCTX-M é endêmicos na região de Ribeirão Preto. Os dados obtidos por este trabalho são importantes porque existem poucos relatos sobre a produção de ESBL por enterobactérias isoladas de líquido céfalo-raquidiano e sangue de pacientes com suspeita de meningite. / Members of Enterobacteriaceae family are cause of cause meningitis associated with nosocomial or secondary infection. The empiric therapy used in patients with suspicion of meningitis is, sometimes, inefficient due to extended-spectrum beta-lactamases (ESBL)- producing, that is the most common mechanism of resistance to cephalosporins in enterobacteria. The main objective of this study was to evaluate ESBL and AmpC-producing Enterobacteriaceae isolated of cerebrospinal fluid and blood from patients with suspicion of meningitis from the region of Ribeirão Preto city, during 2000 to 2005. Combination disk method was used for phenotypic detection and PCR was used to amplify genes encoding ESBL and AmpC. Three (6.52 %) out of 46 enterobacteria isolated in the period studied were detected as ESBL-producing and harbored the blaCTX-M-2 gene. The ESBL-producing enterobacteria were: S. marcescens IAL 19, (isolated in Araraquara city SP - Brazil, 2002), P. mirabilis IAL 29 e E. coli IAL 45 (isolated in Franca city SP- Brazil, respectively, 2003 e 2004). The blaCTX-M-2 gene was detected in three different genera isolated for a long time, suggesting that the blaCTX-M-2 gene is endemic in the region of Ribeirão Preto city. The data generated by this study are important because there are low reports about ESBL-producing enterobacteria isolated of cerebrospinal fluid and blood from patients with suspicion of meningitis.

Made available in DSpace on 2014-12-17T14:05:22Z (GMT). No. of bitstreams: 1 LeonamGC_TESE.pdf: 2406262 bytes, checksum: 604659dd8ff62335f952679dda971b6e (MD5) Previous issue date: 2013-03-19 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Despite advances in antibiotic therapy, bacterial meningitis (BM) remains with high mortality and morbidity rates in worldwide. One important mechanism associated to sequels during disease is the intense inflammatory response which promotes an oxidative burst and release of reactive oxygen species, consequently leading to cell death. Activation of DNA repair enzymes during oxidative stress has been demonstrated in several neurological disorders. APE1/Ref-1 is a multifunctional protein involved in DNA repair and plays a redox function on transcription factors such as NFkB and AP-1.The aim of this study was assess the role of APE1/Ref-1 on inflammatory response and the possibility of its modulation to reduce the sequels of the disease. Firstly it was performed an assay to measure cytokine in cerebrospinal fluid of patients with BM due to Streptococcus pneumoniae and Neisseriae meningitides. Further, a cellular model of inflammation was used to observe the effect of the inhibition of the endonuclease and redox activity of APE1/Ref-1 on cytokine levels. Additionally, APE1/Ref-1 expression in cortex and hippocampus of rat with MB after vitamin B6 treatment was evaluated. Altogether, results showed a similar profile of cytokines in the cerebrospinal fluid of patients from both pathogens, although IFNy showed higher expression in patients with BM caused by S. pneumoniae. On the other hand, inhibitors of APE1/Ref-1 reduced cytokine levels, mainly TNF-?. Reduction of oxidative stress markers was also observed after introduction of inhibitors in the LPS-stimulated cell. In the animal model, BM increased the expression of the protein APE1/Ref-1, while vitamin B6 promoted reduction. Thereby, this data rise important factors to be considered in pathogenesis of BM, e.g., IFNy can be used as prognostic factor during corticosteroid therapy, APE1/Ref-1 can be an important target to modulate the level of inflammation and VIII oxidative stress, and vitamin B6 seems modulates several proteins related to cell death. So, this study highlights a new understanding on the role of APE1/Ref-1 on the inflammation and the oxidative stress during inflammation condition / A meningite bacteriana (MB) ? uma doen?a infecciosa que permanece com altas taxas de mortalidade e morbidade em todo o mundo, principalmente em pa?ses subdesenvolvidos, apesar dos avan?os na antibioticoterapia. Um dos principais mecanismos associados ?s sequelas durante a MB ? a elevada resposta inflamat?ria, que promove uma exacerbada quantidade de esp?cies reativas de oxig?nio (ERO) levando ?s c?lulas a apoptose ou necrose. A ativa??o de enzimas de reparo de DNA durante o estresse oxidativo tem sido demonstrada nas mais diversas desordens. Uma importante enzima envolvida neste processo ? a endonuclease apur?nica/apirimidinica1/fator redox-1 (APE1/Ref-1). Ela ? uma prote?na multifuncional envolvida no reparo de DNA e na redu??o de fatores envolvidos com a resposta inflamat?ria, tais como o fator nuclear kappa B (NFkB) e prote?na ativadora 1 (AP-1). Este estudo teve como objetivo identificar o envolvimento de APE1/Ref-1 na resposta inflamat?ria visando a possibilidade de sua utiliza??o como alvo terap?utico na redu??o de sequelas durante a MB. Para isto, inicialmente foi realizado uma an?lise no perfil de express?o de citocinas em l?quor de pacientes com meningite causada por Streptococcus pneumoniae e Neisseriae meningitidis visando selecionar moduladores inflamat?rios de interesse para ensaios em cultura de c?lula subsequentes. Em seguida, utilizando um modelo celular de indu??o com LPS foi avaliado o efeito da inibi??o da atividade de reparo e redox de APE1 sobre a express?o de citocinas inflamat?rias. Por fim, foi observada a express?o de APE1 no c?rtex (CX) e hipocampo (HC) de ratos com MB frente a uma terapia adjuvante com vitamina B6. Nossos resultados mostraram um perfil de moduladores inflamat?rios muito semelhante no l?quor dos pacientes com MB causada pelos pat?genos estudados, embora interferon gama (IFNy) tenha sido VI significativamente mais expresso em pacientes com S. pneumoniae do que N. meningitidis. Quanto ao uso dos inibidores das fun??es, redox e de reparo, de APE1/Ref-1 no modelo in vitro, houve redu??o significativa na express?o de algumas citocinas, principalmente o fator de necrose tumoral-alfa (TNF-?). Al?m disso, os inibidores demonstraram uma redu??o nos n?veis de ERO nas c?lulas estimuladas com LPS. No modelo animal, a express?o prot?ica de APE1/Ref-1, no CX e HC dos ratos, foi modulada ap?s introdu??o da vitamina B6. Portanto, esses dados fornecem um novo olhar para a fisiopatologia da MB, em que citocinas como IFNy podem ser usadas em um diagn?stico diferencial entre meningites causadas por S. pneumoniae e N. meningitidis. A prote?na de reparo de DNA, APE1/Ref-1, parece ser um alvo potencial na modula??o da resposta inflamat?ria e do estresse oxidativo, bem como a terapia adjuvante com vitamina B6 mostra ter um papel sobre a express?o de APE1/Ref-1. Consequentemente, o conhecimento obtido neste estudo pode ser importante na melhoria do progn?stico da MB, al?m de contribuir para entender a associa??o entre o reparo de DNA e inflama??o / 2020-01-01 / 2020-01-01

Fungal infections are ignored by social and political communities. However, they are estimated to affect more than a billion people, resulting in approximately 11.5 million life-threatening infections in the 'at risk' population and more than 1.5 million deaths annually. Though there have been huge advances in diagnostics and antifungal drug development over the past two decades, however, resource limited settings have not benefited from these advances. The aim of this research was to determine the burden of serious fungal infections in Nigerians with the appropriate underlying diseases. This epidemiological research was conducted across four study populations. Study 1; HIV-infected patients with CD4+ counts < 250 cells/mm³, irrespective of their ART status, a CrAg lateral flow assay was used for detecting cryptococcal antigenaemia (n=214). Study 2; a cross-sectional multicentre survey of TB patients being managed for smear negative or treatment failure TB irrespective of their HIV status (n=208). Study 3; a multicentre histoplasmin skin sensitivity survey amongst healthy HIV-infected and non-HIV infected participants; intradermally; induration ≥ 5 mm was considered to be histoplasmin positive (n=750). Study 4; a prospective cohort study of critically ill patients in a Nigerian ICU (n=71). Two retrospective studies to analyse the clinical picture of serious fungal infections in two at risk populations (HIV/AIDS and neonatal intensive care babies) in Nigerians was also conducted (n=7034; n=2712 respectively). Results revealed an overall seroprevalence of cryptococcal antigenemia of 8.9% with 6 (9.8%) in those with CD4+ cell counts < 100cells/mm³, 4 (5.0%) in the 100-200 group and 9 (12.3%) in 200-250 cells/mm³ group; a CPA prevalence of 8.7% (6.5% had HIV infection and 14.5% were HIV-negative) and a prior subclinical histoplasmosis of 4.4%. The ICU study revealed a 45% healthcare associated infection rate representing an incidence rate of 79/1000 patient-days in the ICU. The retrospective studies revealed a 2.3% rate of neonatal ICI with a case fatality rate of 18.5%. In the 12 years retrospective study 18% had a fungal OI with 88% of patients having initiated ART. In conclusion, serious fungal infections do occur in the at risk population in Nigeria and they constitute a significant public health challenge. Our findings demonstrate that there has been an underestimation of the burden of the problem in Nigerians. There is a dire need to design guidelines for the management of fungal infections in at risk population.