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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.
11

Investigation into mechanisms for antifungal resistance in Aspergillus fumigatus

Fan, Yu Ying January 2021 (has links)
Aspergillus fumigatus is a filamentous saprophytic mold that is found abundantly in the biosphere. A. fumigatus is also an airborne human pathogen and is considered the major cause of aspergillosis, infections caused by inhalation of conidia. In immunocompetent individuals, the spores rarely cause any harm as they are cleared by innate pulmonary defences; however, in immunocompromised patients, the host immune system can fail to clear the inhaled conidia and aspergillosis may develop. Indeed, aspergillosis represents a major cause of morbidity and mortality in these populations. Aspergillosis is commonly treated using triazole and amphotericin B (AMB) antifungal agents. However, the increasing prevalence of triazole resistant strains and emergence of AMB resistance has become a challenge in treatment. To further expand our knowledge on the mechanisms of antifungal resistance in the species, we tested previously known or associated genes for antifungal resistance as well as investigated novel mechanisms via multiple genome-wide association studies (GWAS), which used a total of 211 genomes from A. fumigatus strains in 12 countries. Our results identified many novel mutations related to triazole and AMB resistance. Specifically, using stepwise GWAS analyses, we identified 6 and 18 missense variants to be significantly associated with itraconazole and voriconazole resistance, respectively. A linkage disequilibrium analysis identified six additional missense variants associated with triazole resistance, with two of these six being consistently associated with pan-azole resistance across subsets of samples. Furthermore, examination of known mutation sites and genes overexpressed with triazole exposure found a total of 65 SNPs implicated in triazole resistance. For the AMB study, we identified a total of 34 mutations associated with AMB tolerance using a GWAS. Subsequent analysis with 143 progeny strains, generated from a laboratory cross and genotyped with PCR-RFLP, identified epistatic interactions between five of these SNP sites that impacted growth in different concentrations of AMB. With the expanding immunocompromised population and increasing frequency of antifungal resistance, our results will help in investigating novel resistance mechanisms in A. fumigatus and in expanding the molecular diagnostic toolset in resistance screening, to enable rapid and accurate diagnosis and treatment decision-making. / Thesis / Master of Science (MSc)
12

Non-Occlusive St-Segment Elevated Myocardial Infarction Following the Administration of Liposomal Amphotericin B in the Treatment of Cryptococcal Meningitis

Kullab, Susan M., Patel, Paras D., Lewis, Paul O. 01 October 2020 (has links)
What is known and objective: Liposomal amphotericin B (L-AmB) is the cornerstone of many serious invasive fungal infections. Despite lower frequencies of commonly reported adverse events in clinical trials compared to conventional formulations, post-marketing complications continue to mount. Case description: We present a case of chest pain following the initial dose of L-AmB for cryptococcal meningitis. Electrocardiogram demonstrated no acute electrocardiogram findings. Upon rechallenge, the chest pain worsened was subsequently accompanied by ST-segment elevation. Emergent coronary angiography found no acute findings. What is new and conclusion: Providers should be aware of cardiac complications with L-AmB, including non-occlusive ST-segment elevation.
13

Multiresistenzen in klinischen \(C.glabrata\) Isolaten / Multidrug Resistance in clinical \(C.glabarata\) Isolates

Wilhelm, Hannah January 2024 (has links) (PDF)
Die Zahl invasiver Pilzinfektionen ausgelöst durch C. glabrata steigt zunehmend und auch die Ausbildung multipler Resistenzen wird immer häufiger registriert. In dieser Arbeit wurden zwei klinische MDR-C. glabrata-Stämme systematisch analysiert, um den Ursprung der Mehrfachresistenz zu finden. Aufgefallen waren jene Isolate in vorhergehenden Untersuchungen von Aldejohann et. al., die 176 Stämme, die dem Referenzzentrum NRZ-Myk zugesandt wurden, auf ihr Resistenzverhalten gegen Echinocandine analysierten und auf FKS-Mutationen untersuchten. Die Isolate CG22 und CG56 zeigten ein Resistenzverhalten gegen Anidulafungin ohne eine FKS-Mutation aufzuweisen. In Mehrfachtestungen wurde das einheitliche Verhalten von CG56 in zehn Einzelkolonien verifiziert, um Mischkulturen oder heterogenes Verhalten innerhalb des Isolates ausschließen zu können. Nach Analyse der gesamten Genomsequenz von CG56 zeigte sich eine Mutation kurz vor der HS-Region von FKS2, die eine Erklärung für das Resistenzverhalten zu liefern scheint. Neben der Mutation in FKS2 wurde ebenfalls eine Mutation in FKS1 und in ERG3 bestätigt. Die Mutation in ERG3 führt zu einer Verschiebung im Sterolsynthesepathway und zu einer Neuverteilung der Zellmembranbestandteile. Das klinische Isolat CG22 fällt mit Resistenzen gegen Azole, Echinocandine und Amphotericin B auf und zeigte ebenfalls eine Mutationen in ERG3. Zusätzlich dazu ergab sich eine Loss-of- Function-Mutation in ERG4 und damit verbunden einen massiv reduzierten Ergosterolgehalt der Zellmembran. Die seltene Kombination aus ERG3 und ERG4 Mutation scheint die Erklärung für die außergewöhnliche Amphotericin B-Resistenz von CG22 zu liefern und wird hier als erstmals bei einem C. glabrata Isolat beschrieben. Dieser besondere Stamm, der sogar als panresistent bezeichnet werden kann, sollte Bestandteil weiterer Forschung werden. Der Sterolsynthesepathway dient als Angriffspunkt vieler Antimykotika und kann durch seine vielen Intermediate und abweichenden Abläufen zu unterschiedlichen Stoffwechselendprodukten führen. Der Ergosterolgehalt der Zellmembran eines C. glabrata-Stammes kann weitere Rückschlüsse auf die Empfindlichkeit des Isolates geben und somit die Chancen des Therapieerfolges der Antimykotikagabe besser vorhersagen und könnte somit einen vielversprechenden Beitrag zur Behandlung lebensbedrohlicher Candidosen leisten. / The number of invasive fungal infections caused by C. glabrata is increasing and the development of resistance to multiple drug classes is also being recorded more frequently. In this study, two clinical MDR C. glabrata strains were systematically analyzed to find the origin of their Multidrug Resistance. These isolates had attracted attention in previous studies by Aldejohann et. al. who studied 176 strains that have been sent to the NRZ-Myk reference center. The strains have been analyzed for their resistance to echinocandins and have been examined for mutations in FKS1 and FKS2 hotspots. The isolates CG22 and CG56 showed resistance to anidulafungin without showing mutation in the FKS hotspots. In multiple testing, the uniform behavior of CG56 was verified in ten individual colonies in order to exclude mixed cultures or heterogeneous behavior within the isolate. Analysis of the entire genome sequence of CG56 revealed a mutation just upstream of the HS region of FKS2, which appears to provide an explanation for the resistance behavior. In addition to the mutation in FKS2, a mutation in FKS1 and ERG3 was also confirmed. The mutation in ERG3 leads to a shift in the sterol synthesis pathway and to a redistribution of the cell membrane components. The clinical isolate CG22 was found to be resistant to azoles, echinocandins and amphotericin B. CG22 showed a mutation in ERG3 and additionally a loss-of-function mutation in ERG4. This leads to a massively reduced ergosterol content of the cell membrane. The rare combination of ERG3 and ERG4 mutation seems to explain the extraordinary amphotericin B resistance of CG22 and is described for the first time in a C. glabrata isolate. This particular strain, which can even be described as panresistant, should become part of further research. The sterol synthesis pathway serves as a target for many antimycotics and can lead to different metabolic products due to its many intermediates and divergent processes. The ergosterol content of the cell membrane of a C. glabrata strain can provide further information on the susceptibility of the isolate. This could possibly predict the chances of therapeutic success of antimycotic treatment better and could therefore make a promising contribution to the treatment of life-threatening candidiasis.
14

Resistenzmechanismen gegen Amphotericin B in humanpathogenen Hefepilzen / Resistance mechanism to amphotericin B in human pathogenic yeasts

Junghanns, Lara Madeleine January 2024 (has links) (PDF)
Die 2009 erstmals entdeckte Spezies C. auris erlangte binnen kürzester Zeit zunehmend weltweite Aufmerksamkeit. Vor allem die Tendenz der Multiresistenzentwicklung und das rasche Auslösen von nosokomialen Infektionen erschweren den Umgang und die Therapie von C. auris Infektionen im Vergleich zu anderen Candida Spezien. Diese Dissertationsarbeit umfasst eine systematische Resistenzanalyse der im NRZMyk vorhandenen Stammsammlung aus C. auris und C. parapsilosis Isolaten, um Aufschluss über den Wirkmechanismus von Amphotericin B in Hefepilzen zu erlangen. Anhand der zunächst durchgeführten Amphotericin B-Resistenztestungen kristallisierten sich CAU37 und CAU43 mit MHK-Werten bis zu 12 µg/ml als stark Amphotericin B-resistente Isolate heraus. Die Analyse der Sequenzierungsergebnisse zeigte bei beiden Stämmen eine Mutation im ERG4 Gen an Position 576, welche nicht eindeutig als alleinige Ursache für die verminderte Amphotericin B-Empfindlichkeit festgelegt werden konnte. Dennoch wurde im Rahmen eines Survival Assays bei beiden Amphotericin B-resistenten Isolaten anfänglich eine konzentrationsabhängige Aktivität gegenüber Amphotericin B festgestellt, bevor ein Nachwachsen der Kulturen beobachtet wurde. Somit wurde die Vermutung aufgestellt, dass lediglich ein Teil der aufgebrachten Candida-Zellen abgetötet wird und dies in einer Vermehrung der überlebenden Zellen resultiert. Des Weiteren konnte im Rahmen von Resistenztestungen mit dem Sphingolipidinhibitor Myriocin nachgewiesen werden, dass vor allem in Amphotericin B-resistenten Isolaten eine deutliche Wirkungsverstärkung des Polyens hervorgerufen wird. Diese Sensitivitätssteigerung ist allgemein bei allen C. auris Isolaten zu beobachten, fällt bei resistenten Stämmen jedoch deutlich stärker aus. Hierdurch kam die Annahme auf, dass Amphotericin B-Resistenzen auch in möglichen Veränderungen des Sphingolipid-Haushaltes begründet sein könnten. Darüber hinaus scheint Myriocin keinen Einfluss auf Fluconazol-resistente oder FKS-mutierte Echinocandin-resistente C. auris Stämme zu haben. Das ebenfalls untersuchte und von Myriocin abgeleitete Medikament Fingolimod hatte jedoch ebenfalls keinen wirkungsverstärkenden Effekt. Allerdings reagierte ein Großteil der C. auris Isolate (57,6 %) sensitiv gegenüber dem neusten medizinisch bekannten Triazol Isavuconazol und es konnte erstmalig ein ECV-Wert von 0,03125 µg/ml festgelegt werden. Ein valider Vergleich von C. auris zu C. parapsilosis war aufgrund der mangelnden Anzahl an C. parapsilosis Isolaten jedoch nicht möglich / The species C. auris, which was first discovered in 2009, quickly attracted worldwide attention. In particular, the development of multidrug resistance and the rapid onset of nosocomial infections complicate the management and treatment of C. auris infections compared to other Candida species. This dissertation comprises a systematic resistance analysis of the strain collection available at the NRZMyk from C. auris and C. parapsilosis isolates in order to shed light on the mechanism of action of amphotericin B in yeast fungi. CAU37 and CAU43 ermerged as highly amphotericin B-resistant isolates in the initially performed amphotericin B resistance tests, with MIC values up to 12 µg/ml. Sequencing results showed a mutation in the ERG4 gene at position 576 in both strains, which can`t be clearly identified as the main cause of the reduced susceptibility to amphotericin B. Nevertheless both amphotericin B-resistant isolates initially showed a concentration dependent activity against amphotericin B, followed by a regrowth of the cultures. The hypothesis is, that only some of the applied Candida cells are killed, resulting in a proliferation of the surviving cells. Furthermore the resistance tests with the sphingolipid inhibitor Myriocin in combination with amphotericin B showed that sublethal myriocin concentrations increased the C. auris susceptibility to amphotericin B. This increase in sensitivity is generally observed in all C. auris isolates, but is significantly stronger in resistant strains. This leeds to the assumption that amphotericin B resistance can also be due to possible changes in the sphingolipid balance. Furthermore, myriocin does not appear to have any influence on fluconazole-resistant or FKS-mutated echinocandin-resistant C. auris strains. Fingolimod, a drug also investigated and derived from Myriocin, doesn`t have any enhancing effect either. However the majority of C. auris isolates (57.6 %) reacted sensitively to the latest medically known triazole isavuconazole and for the first time an ECV value of of 0.03125 µg/ml could be determined. A valid comparison of C. auris to C. parapsilosis was not possible due to the lack of C. parapsilosis isolates.
15

Intérêt de la lyophilisation pour améliorer la stabilité des microémulsions chargées en Amphotéricine B destinées au traitement de la leishmaniose / Lyophilization as a tool for enhance the stability of microemulsion systems containing Amphotericin B for leishmaniasis treatment

Do Vale Morais, Andreza 20 October 2017 (has links)
La leishmaniose viscérale est une maladie tropicale négligée et létale en l’absence de traitement. L’Amphotéricine B (AmB) est une molécule efficace mais sa forme conventionnelle, Fungizone®, conduit à une toxicité limitant les doses tandis que les formulations lipidiques moins toxiques telles que l’Ambisome® sont très coûteuses. Ainsi, le besoin de nouvelles formes thérapeutiques à la fois non toxiques et peu coûteuses subsiste actuellement. Dans ce travail, nous avons étudié deux solutions possibles : la Fungizone® chauffée (H-AmB) et une microémulsion chargée en AmB (MEAmB). En ce qui concerne la microémulsion, une forme lyophilisée est souhaitable afin de s’affranchir des risques d’hydrolyse et de contamination microbienne. Les objectifs de la thèse étaient de développer les deux nouvelles formes, d’évaluer la toxicité et l’efficacité de H-AmB et MEAmB contre Leishmania donovani (souche LV9) in-vitro et in-vivo et également d’optimiser la lyophilisation de la microémulsion.La microémulsion MEAmB est composée de gouttelettes sphériques dont le diamètre moyen est proche de 35 nm et a montré un comportement rhéologique de type newtonien. L’analyse spectroscopique de H-AmB a révélé la formation de super-agrégats qui sont moins toxiques que d’autres états d’agrégation. La MeAmB ainsi que l’H-AmB ont montré une activité antiparasitaire équivalente à celle d’AmBisome® sur les formes axénique et intramacrophagique de L. donovani. L’indice de sélectivité pour ces deux formulations est élevé, en contraste avec celui de la Fungizone® native. De plus, à la différence d’AmBisome®, elles ont montré une activité importante sur des souches résistantes à l’AmB. L’activité anti-leishmanienne in-vivo des nouvelles formulations est comparable aux formulations de référence. De même, aucune différence significative des marqueurs de toxicité rénale et hépatique n’a pu être observée. Ainsi, l’H-AmB et la MEAmB pourraient être considérées comme des traitements alternatifs de la leishmaniose viscérale, avec l’avantage d’être moins onéreuses à produire que l’Ambisome®.Afin d’optimiser le procédé de lyophilisation de la MEAmB, un plan d’expérience a été mis en œuvre. Ainsi, la taille des gouttelettes est minimisée par l’utilisation de 5% de maltose comme cryoprotectant, avec une température de congélation de -80°C et un temps total de lyophilisation de 24h. Par ailleurs, aucune modification significative de la teneur en AmB n’a été observée après la lyophilisation. Ainsi, la MEAmB lyophilisée est stable et pourrait éviter la dégradation due à la présence d’eau. / Visceral leishmaniasis is a neglected tropical disease that can be fatal if left untreated. Amphotericin B (AmB) is effective in the treatment of this disease, but the conventional formulation, Fungizone® has dose-limiting toxicity while the less toxic lipid-based forms such as Ambisome® are expensive. Therefore, the need for new therapeutic systems remains. In this respect, the heating of the Fungizone® formulation (H-AmB), and the development of a microemulsion (ME) containing AmB (MEAmB) are possible solutions. In addition, it is desirable to remove water from microemulsion systems in order to reduce instability due to microbiological contamination and hydrolysis. Therefore, the objective of this work was to develop and to evaluate the activity and toxicity in vitro and in vivo of H-AmB and MEAmB against Leishmania donovani (strain LV9) and, furthermore, to optimize a lyophilized microemulsion system containing AmB. Rheological, size and morphology studies showed that MEAmB presented average droplet sizes of 35 nm, a Newtonian behavior and spherical morphology. Spectroscopic characterization of H-AmB showed the formation of superaggregates, which are less toxic than the other states of aggregation. In-vitro evaluation on both the axenic and intramacrophagic amastigote forms showed that H-AmB and MEAmB showed similar activity to Ambisome®. A high selectivity index of H-AmB and MEAmB was observed compared with unheated Fungizone®. Furthermore, both new formulations showed high activity against AmB-resistant strains compared with Ambisome®. In-vivo experiments designed to evaluate their activity and toxicity did not reveal significant differences in activity between the new and reference formulations. There were no significant differences either in indicators of renal and hepatic toxicity. Therefore, both H-AmB and MEAmB can be used as an alternative for the treatment of LV9, presenting an advantage over Ambisome® in their lower costs of production. Therefore, a complete experimental design was performed in order to optimize the lyophilisation of the microemulsion system. It was observed that microemulsions with smaller droplet sizes were obtained using maltose as a cryoprotectant at a concentration of 5%, with freezing at -80 ° C, and a lyophilization process period of 24 h. Furthermore, it was observed that ME containing AmB showed no significant changes in drug content before and after the lyophilization process. Therefore, in its lyophilized form, the ME can remain stable and avoid degradation due to the presence of water.
16

Safety and Efficacy of Itraconazole Compared to Amphotericin B as Empirical Antifungal Therapy for Neutropenic Fever in Patients with Haematological Malignancy

Schuler, Ulrich, Bammer, Susanne, Aulitzky, Walter E., Binder, Claudia, Böhme, Angelika, Egerer, Gerlinde, Sandherr, Michael, Schwerdtfeger, Rainer, Silling, Gerda, Wandt, Hannes, Glasmacher, Axel, Ehninger, Gerhard 24 February 2014 (has links) (PDF)
Safety, tolerability and efficacy of itraconazole and amphotericin B (AMB) were compared for empirical antifungal treatment of febrile neutropenic cancer patients. Patients and Methods: In an open, randomised study, 162 patients with at least 72 h of antimicrobial treatment received either intravenous followed by oral itraconazole suspension or intravenous AMB for a maximum of 28 days. Permanent discontinuation of study medication due to any adverse event was the primary safety parameter. Efficacy parameters included response and success rate for both treatment groups. Results: Significantly fewer itraconazole patients discontinued treatment due to any adverse event (22.2 vs. 56.8% AMB; p < 0.0001). The main reason for discontinuation was a rise in serum creatinine (1.2% itraconazole vs. 23.5% AMB). Renal toxicity was significantly higher and more drug-related adverse events occurred in the AMB group. Intention-to-treat (ITT) analysis showed favourable efficacy for itraconazole: response and success rate were both significantly higher than for AMB (61.7 vs. 42% and 70.4 vs. 49.3%, both p < 0.0001). Treatment failure was markedly reduced in itraconazole patients (25.9 vs. 43.2%), largely due to the better tolerability. Conclusions: Itraconazole was tolerated significantly better than conventional AMB and also showed advantages regarding efficacy. This study confirms the role of itraconazole as a useful and safe agent in empirical antifungal therapy of febrile neutropenic cancer patients. / Hintergrund: Es wurden die Sicherheit, Verträglichkeit und Wirksamkeit von Itraconazol und Amphotericin B (AMB) in der antimykotischen Therapie der persistierend febrilen Neutropenie verglichen. Patienten und Methoden: In einer offenen, randomisierten Studie erhielten 162 Patienten mit mindestens 72-stündiger antibiotischer Therapie entweder Itraconazol (erst intravenös, dann oral) oder AMB (intravenös) für maximal 28 Tage. Primärer Sicherheitsparameter war die dauerhafte Unterbrechung der Studienmedikation aufgrund von Nebenwirkungen. Die Wirksamkeitsparameter umfassten die Ansprech- und Erfolgsrate für beide Behandlungsgruppen. Ergebnisse: Signifikant weniger Itraconazol-Patienten brachen die Behandlung wegen Nebenwirkungen ab (22,2 vs. 56,8% AMB; p < 0,0001). Hauptursache für Studienabbrüche war der Anstieg des Serum-Kreatinin-Spiegels (1,2% Itraconazol vs. 23,5% AMB). Nephrotoxische und weitere Nebenwirkungen traten im AMB-Studienarm signifikant häufiger auf. Intention-to-Treat (ITT)-Analysen zeigten eine bessere Wirksamkeit von Itraconazol: Ansprech- und Erfolgsrate waren signifikant höher als unter AMB (61,7 vs. 42% und 70,4 vs. 49,3%, beide p < 0,0001). Behandlungsversagen trat bei Itraconazol-Patienten merklich weniger auf (25,9 vs. 43,2%). Schlussfolgerungen: Die Verträglichkeit von Itraconazol war signifikant höher als beim herkömmlichen AMB. Itraconazol zeigte ebenfalls Vorteile in der Wirksamkeit. Diese Studie bestätigt die Rolle von Itraconazol als sinnvolles und sicheres Medikament in der empirischen antimykotischen Therapie von fiebrigen neutropenischen Tumorpatienten. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
17

Safety and Efficacy of Itraconazole Compared to Amphotericin B as Empirical Antifungal Therapy for Neutropenic Fever in Patients with Haematological Malignancy

Schuler, Ulrich, Bammer, Susanne, Aulitzky, Walter E., Binder, Claudia, Böhme, Angelika, Egerer, Gerlinde, Sandherr, Michael, Schwerdtfeger, Rainer, Silling, Gerda, Wandt, Hannes, Glasmacher, Axel, Ehninger, Gerhard January 2007 (has links)
Safety, tolerability and efficacy of itraconazole and amphotericin B (AMB) were compared for empirical antifungal treatment of febrile neutropenic cancer patients. Patients and Methods: In an open, randomised study, 162 patients with at least 72 h of antimicrobial treatment received either intravenous followed by oral itraconazole suspension or intravenous AMB for a maximum of 28 days. Permanent discontinuation of study medication due to any adverse event was the primary safety parameter. Efficacy parameters included response and success rate for both treatment groups. Results: Significantly fewer itraconazole patients discontinued treatment due to any adverse event (22.2 vs. 56.8% AMB; p < 0.0001). The main reason for discontinuation was a rise in serum creatinine (1.2% itraconazole vs. 23.5% AMB). Renal toxicity was significantly higher and more drug-related adverse events occurred in the AMB group. Intention-to-treat (ITT) analysis showed favourable efficacy for itraconazole: response and success rate were both significantly higher than for AMB (61.7 vs. 42% and 70.4 vs. 49.3%, both p < 0.0001). Treatment failure was markedly reduced in itraconazole patients (25.9 vs. 43.2%), largely due to the better tolerability. Conclusions: Itraconazole was tolerated significantly better than conventional AMB and also showed advantages regarding efficacy. This study confirms the role of itraconazole as a useful and safe agent in empirical antifungal therapy of febrile neutropenic cancer patients. / Hintergrund: Es wurden die Sicherheit, Verträglichkeit und Wirksamkeit von Itraconazol und Amphotericin B (AMB) in der antimykotischen Therapie der persistierend febrilen Neutropenie verglichen. Patienten und Methoden: In einer offenen, randomisierten Studie erhielten 162 Patienten mit mindestens 72-stündiger antibiotischer Therapie entweder Itraconazol (erst intravenös, dann oral) oder AMB (intravenös) für maximal 28 Tage. Primärer Sicherheitsparameter war die dauerhafte Unterbrechung der Studienmedikation aufgrund von Nebenwirkungen. Die Wirksamkeitsparameter umfassten die Ansprech- und Erfolgsrate für beide Behandlungsgruppen. Ergebnisse: Signifikant weniger Itraconazol-Patienten brachen die Behandlung wegen Nebenwirkungen ab (22,2 vs. 56,8% AMB; p < 0,0001). Hauptursache für Studienabbrüche war der Anstieg des Serum-Kreatinin-Spiegels (1,2% Itraconazol vs. 23,5% AMB). Nephrotoxische und weitere Nebenwirkungen traten im AMB-Studienarm signifikant häufiger auf. Intention-to-Treat (ITT)-Analysen zeigten eine bessere Wirksamkeit von Itraconazol: Ansprech- und Erfolgsrate waren signifikant höher als unter AMB (61,7 vs. 42% und 70,4 vs. 49,3%, beide p < 0,0001). Behandlungsversagen trat bei Itraconazol-Patienten merklich weniger auf (25,9 vs. 43,2%). Schlussfolgerungen: Die Verträglichkeit von Itraconazol war signifikant höher als beim herkömmlichen AMB. Itraconazol zeigte ebenfalls Vorteile in der Wirksamkeit. Diese Studie bestätigt die Rolle von Itraconazol als sinnvolles und sicheres Medikament in der empirischen antimykotischen Therapie von fiebrigen neutropenischen Tumorpatienten. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
18

ALTERAÇÕES LABORATORIAIS E EFEITOS ADVERSOS NO TRATAMENTO DA LEISHMANIOSE VISCERAL: HOSPITAL - ARAGUAÍNA-TO

Tobias, Célia Alves dos Santos 14 December 2009 (has links)
Made available in DSpace on 2016-08-10T10:29:38Z (GMT). No. of bitstreams: 1 CELIA ALVES DOS SANTOS TOBIAS.pdf: 5019796 bytes, checksum: 74c8086d1f7a5a95e1b31395c6183bf0 (MD5) Previous issue date: 2009-12-14 / To describe the laboratory abnormalities and adverse events in patients presenting with visceral leishmaniasis treated by antimony in a reference center for tropical diseases in Araguaina TO held a retrospective study by systematic analysis of medical records in order to identify the laboratory abnormalities and adverse effects caused by the use of leishmanicidas, between the months of January to December 2008, evaluating the clinical, laboratory and treatment of patients at the Hospital for Tropical Diseases (HDT) in 253 patients. Although the drugs used effectively combat the parasite, they can cause undesirable side effects, whether by active ingredient or its metabolites. The diagnostic methods used were bone marrow aspirates (2.4%) and serology for immunofluorescence (94%), and (3.5%) probably the criterion was the clinical and epidemiological. Meglumine antimoniate showed high efficiency (70%) and more adverse effects reported were: liver enzyme elevations (0.45%) and pancreatic (1.79%), electrocardiographic abnormalities (4.07%), minor and reversible. Pancreatitis a serious adverse reaction was reported in 4 cases. Amphotericin B was used in 65 patients (25.6%), with 28 patients (11%) had failures in responding to glucantime, replaced by amphotericin B, 14 patients had recurrences and 14 (5.53%) died . The liposomal amphotericin B was used in 2 cases with severe kidney problems. Among the patients studied, 141 (55.73%) males, 112 females and age groups below 10 years was equivalent to 70%. In therapy with antimonials, 10 patients (4.5%) had arthralgia, 8 patients (3.6%) myalgia; 67pacientes (30.14%) weakness, 57 (25.6%) vomiting, (19.8%) change in weight, 28 (12.6%) palpitations. There were several signs and symptoms at admission: fever (95.5%), splenomegaly (60.7%), and hepatomegaly (49.1%). In hematological data were no changes in 106 (47.3%) in the other patients (118), the results were normal, because it is an emerging and very important, it is necessary to adopt a protocol for follow-up function renal and laboratory tests aimed at detecting abnormalities in the post-treatment and use of drugs that reduce these adverse effects. / Para descrever as alterações laboratoriais e efeitos adversos de pacientes apresentando quadro de leishmaniose visceral, tratados com antimoniais em um centro de referência para doenças tropicais em Araguaína TO realizou-se um estudo retrospectivo através da análise sistematizada de prontuários com o objetivo de identificar as alterações laboratoriais e efeitos adversos causados pelo uso dos leishmanicidas, entre os meses de janeiro a dezembro de 2008, avaliando os aspectos clínicos, laboratoriais e terapêuticos de pacientes no Hospital de Doenças Tropicais (HDT) em 253 pacientes. Apesar das drogas utilizadas combaterem eficazmente o parasito, elas podem ocasionar efeitos colaterais indesejáveis, seja pelo próprio princípio ativo ou pelos seus metabólitos. Os métodos de diagnósticos utilizados foram aspirados medular (2,4%) e sorologia para Imunofluorescência (94%); e em (3,5%) provavelmente, o critério foi o clínico-epidemiológico. O antimoniato de meglumina apresentou elevada eficácia (70%) e os efeitos adversos mais relatados foram: elevações das enzimas hepáticas (0,45%) e pancreáticas (1,79%), alterações eletrocardiográficas (4,07%), pouco graves e reversíveis. Pancreatite uma reação adversa grave foi relatado em 4 casos. A anfotericina B foi utilizada em 65 pacientes (25,6%); sendo que 28 pacientes (11%) tiveram falhas na resposta com glucantime, substituído por anfotericina B; 14 pacientes tiveram recidivas e 14 (5,53%) foram a óbito. A anfotericina B lipossomal foi usada em 2 casos com problemas renais graves. Entre os pacientes analisados, 141 (55,73%) do sexo masculino, 112 do sexo feminino e a faixa etária em grupos menor que 10 anos foi equivalente a 70%. Na terapia com antimoniais, 10 pacientes (4,5%) tiveram artralgia; 8 pacientes(3,6%) mialgia; 67pacientes (30,14%) fraqueza; 57 (25,6%) vômitos; (19,8%) alteração do peso; 28 (12,6%) palpitação. Houve vários sinais e sintomas na internação: febre, (95,5%); esplenomegalia (60,7%); hepatomegalia (49,1%). Nos dados hematológicos houve alterações em 106 (47,3%); nos demais pacientes (118), os resultados se encontravam normais; por ser uma doença emergente e de grande importância, faz-se necessário a adoção de um protocolo para seguimento da função renal e exames laboratoriais visando à detecção de anormalidades no pós-tratamento e utilização de drogas que diminuam esses efeitos adversos.
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Estudo de subemulsões e microemulsões contendo anfotericina B para administração oral /

Franzini, Cristina Maria. January 2006 (has links)
Orientador: Anselmo Gomes de Oliveira / Banca: Marco Vinícius Chaud / Banca: Renata Fonseca Vianna Lopez / Resumo: O objetivo esse trabalho foi o desenvolvimento de sistemas microemulsionados ou subemulsionados estabilizados por fosfatidilcolina de soja (FS) associada à tensoativos hidrofílicos para veiculação de AmB. Foi avaliada a utilização de pluronic (PLU) como co-tensoativo e observou-se o predomínio de sistemas mais viscosos. O estudo do comportamento reológico das MEs, mostrou que todas as amostras apresentaram comportamento Newtoniano, mantendo a viscosidade constante independente da velocidade de deformação. Os estados de agregação da AmB foram avaliados através de seus espectros de absorção relativos às diferentes concentrações, inclusão em ciclodextrinas e incorporação no sistema microemulsionado selecionado. Foi verificada uma modificação relativa na proporção de monômeros do fármaco. A técnica de nefelometria foi realizada e indicou aumento no tamanho das gotículas da ME com o aumento da concentração da AmB. Verificou-se que a incorporação de AmB nos sistemas desenvolvidos é dependente da proporção relativa da fase interna oleosa. A liberação de AmB, in vitro, é mais prolongada à medida que aumenta a proporção de fase interna oleosa. Os sistemas microemulsionados e subemulsionados mostraram-se eficazes na veiculação de AmB apresentando-se como sistema reservatório facilitando a liberação prolongada. / Abstract: The objective of this work was the development of subemulsified and microemulsified systems stabilized by soya phosphatidylcholine (FS) and/or FS associated to hydrophylic surfactants to AmB veiculation. It was evaluated the use of pluronic (PLU) as co-surfactant and it was observed the predominancy of the more viscose systems. The study of the rheological behavior of MEs verified that all the samples have presented Newtonian behavior, maintaining the viscosity constant independent of the deformation speed. The states of aggregation of the AmB have been evaluated through its relative absorption specters to the different concentrations, inclusion in cyclodextrins and incorporation in the selected microemulsion system. A relative modification in the proportion of monomers of the drug was verified. The Nefelometry technique was performed and showed increase in the droplets size of the ME with increase to the AmB concentration. It was verified that the AmB incorporation in the developed systems is dependent on the oil phase. The in vitro release of AmB is more prolonged as long as the internal oil phase increases. The microemulsified and subemulsified systems appear as more effective in the AmB veiculation presenting themselves as reservatory system, facilitating the prolonged release. / Mestre
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Cellular differentiation and antibiotic production by Streptomyces nodosus immobilised in alginate capsules

Pereira, Tanya, University of Western Sydney, College of Health and Science, School of Natural Sciences January 2007 (has links)
Encapsulation is a novel technique that involves the entrapment of materials such as cells, enzymes or chemicals within a semi-permeable matrix and is being explored as a drug delivery system. This project investigated the encapsulation of Streptomyces nodosus in alginate to assess whether this organism can produce the antifungal drug amphotericin B from within the matrix. New methods were developed to immobilise S. nodosus mycelia and spores in alginate capsules, assess bacterial viability and detect ng mL–1 quantities of amphotericin B in culture fluids. When capsules were cultured and cell proliferation was encouraged, organisms formed protrusions on the surface of the capsules. Differentiated branched hyphae that never progressed to sporogenic hyphae were observed on the surface of these structures. Viability was maintained for up to 30 days and low levels of amphotericin B were produced. The emergence of a co-existing free-dwelling population was also observed. Culturing immobilised organisms using conditioned media from an amphotericin deficient S. nodosus strain, augmented the development of the free-dwelling population resulting in the detection of amphotericin B in the culture fluid and full differentiation to sporogenic hyphae. This is the first report of sporulation of S. nodosus in liquid environments and demonstrates that immobilised S. nodosus can produce antibiotics. The sporulation of free-dwelling organisms was also induced using conditioned media and manipulation of quorum size, indicating a solid surface is not required for sporulation. Conditioned media from other Streptomyces spp. induced variable responses including sporulation, pigment formation and antibiotic production, possibly demonstrating communication between species and/or alteration in nutritional status. This new model for the life cycle of S. nodosus will permit the study of developmental pathways, antibiotic production, microbial community structure and inter-species and intra-species signalling. / Doctor of Philosophy (PhD)

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