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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

Feo-hifomicose no Rio Grande do Sul : apresentação de série de casos e comentários sobre o tema em nosso meio / Presentation of series of cases and comments on the subject in our environment

Salles, Emily Ferreira January 2010 (has links)
Feo-hifomicose refere-se a infecções por fungos pigmentados escuros. Revisamos a casuística brasileira entre 1953 e 2010, apresentando as características clínico-epidemiológicas e diagnósticas de 17 casos. Nas quais a coloração de hematoxilina-eosina foi usada para visualizar alterações estruturais nas lesões; a coloração da prata para identificação dos microrganismos; e coloração de Fontana-Masson confirmou a melanina na parede fúngica. Os fungos cresceram sob aspecto de micélio e produziam pigmentos de melanina, que dão às colônias cor negra característica. A observação das características microscópicas dos cultivos forneceu a identificação etiológica. A feo-hifomicose está amplamente disseminada no Brasil. Entretanto, é subestimada devido a fixação das biopsias em formol, o que impede o isolamento em cultivos. / Phaeohyphomycosis refers to infection caused by darkly pigmented fungi. We reviewed the Brazilian casuistic from 1953 to 2010 and presented the clinicalepidemiologic and diagnostic features of addictional 17 cases. In the cases hematoxilin and eosin stain was used to look for structural changes of the infected lesion; Gomori’s methenamine-silver stain identified these organisms; and Fontana-Masson staining confirm the presence of melanin fungal cell wall. The organisms formed mycelial colonies and produced melanin-like pigments that give the colonies the characteristic dark color. The microscopic study of cultures identified etiology. The phaeohyphomycosis is a widespread tropical disease in Brazil. However, it is underestimated due to formalin fixation tissue specimens that oppose the prior cultures.
2

Feo-hifomicose no Rio Grande do Sul : apresentação de série de casos e comentários sobre o tema em nosso meio / Presentation of series of cases and comments on the subject in our environment

Salles, Emily Ferreira January 2010 (has links)
Feo-hifomicose refere-se a infecções por fungos pigmentados escuros. Revisamos a casuística brasileira entre 1953 e 2010, apresentando as características clínico-epidemiológicas e diagnósticas de 17 casos. Nas quais a coloração de hematoxilina-eosina foi usada para visualizar alterações estruturais nas lesões; a coloração da prata para identificação dos microrganismos; e coloração de Fontana-Masson confirmou a melanina na parede fúngica. Os fungos cresceram sob aspecto de micélio e produziam pigmentos de melanina, que dão às colônias cor negra característica. A observação das características microscópicas dos cultivos forneceu a identificação etiológica. A feo-hifomicose está amplamente disseminada no Brasil. Entretanto, é subestimada devido a fixação das biopsias em formol, o que impede o isolamento em cultivos. / Phaeohyphomycosis refers to infection caused by darkly pigmented fungi. We reviewed the Brazilian casuistic from 1953 to 2010 and presented the clinicalepidemiologic and diagnostic features of addictional 17 cases. In the cases hematoxilin and eosin stain was used to look for structural changes of the infected lesion; Gomori’s methenamine-silver stain identified these organisms; and Fontana-Masson staining confirm the presence of melanin fungal cell wall. The organisms formed mycelial colonies and produced melanin-like pigments that give the colonies the characteristic dark color. The microscopic study of cultures identified etiology. The phaeohyphomycosis is a widespread tropical disease in Brazil. However, it is underestimated due to formalin fixation tissue specimens that oppose the prior cultures.
3

Feo-hifomicose no Rio Grande do Sul : apresentação de série de casos e comentários sobre o tema em nosso meio / Presentation of series of cases and comments on the subject in our environment

Salles, Emily Ferreira January 2010 (has links)
Feo-hifomicose refere-se a infecções por fungos pigmentados escuros. Revisamos a casuística brasileira entre 1953 e 2010, apresentando as características clínico-epidemiológicas e diagnósticas de 17 casos. Nas quais a coloração de hematoxilina-eosina foi usada para visualizar alterações estruturais nas lesões; a coloração da prata para identificação dos microrganismos; e coloração de Fontana-Masson confirmou a melanina na parede fúngica. Os fungos cresceram sob aspecto de micélio e produziam pigmentos de melanina, que dão às colônias cor negra característica. A observação das características microscópicas dos cultivos forneceu a identificação etiológica. A feo-hifomicose está amplamente disseminada no Brasil. Entretanto, é subestimada devido a fixação das biopsias em formol, o que impede o isolamento em cultivos. / Phaeohyphomycosis refers to infection caused by darkly pigmented fungi. We reviewed the Brazilian casuistic from 1953 to 2010 and presented the clinicalepidemiologic and diagnostic features of addictional 17 cases. In the cases hematoxilin and eosin stain was used to look for structural changes of the infected lesion; Gomori’s methenamine-silver stain identified these organisms; and Fontana-Masson staining confirm the presence of melanin fungal cell wall. The organisms formed mycelial colonies and produced melanin-like pigments that give the colonies the characteristic dark color. The microscopic study of cultures identified etiology. The phaeohyphomycosis is a widespread tropical disease in Brazil. However, it is underestimated due to formalin fixation tissue specimens that oppose the prior cultures.
4

Invasive fungal infections and CARD9 deficiency / Infections fongiques invasives et déficit en CARD9

Lanternier, Fanny 22 November 2013 (has links)
Les infections fongiques invasives, sont des infections sévères grevées d’une lourde mortalité. Elles sont actuellement un problème majeur de santé publique et leur incidence augmente. Les candidémies représentent la quatrième cause d’infection hématogène nosocomiale aux Etats-Unis, les cryptococcoses sont responsables de 600 000 décès chaque année en Afrique et l’aspergillose invasive infecte 10% des patients transplantés de cellules souches. La mortalité de ces infections reste élevée avec des taux de mortalité de 50, 15 et 40% respectivement. L’augmentation de leur incidence est due à l’accroissement des populations immunodéprimées à risque de développer des infections fongiques en raison de l’augmentation des thérapeutiques immunosuppressives et de l’allongement de la durée de vie des patients immunodéprimés. Les infections fongiques invasives surviennent chez des patients immunodéprimés, majoritairement dans un contexte d’immunodépression acquise (neutropénie, chimiothérapie, greffe de cellules souches périphériques ou transplantation d’organe solide, diabète, infection par le virus de l’immunodéficience humaine), mais également secondairement à un déficit immunitaire héréditaire (granulomatose septique chronique, déficit immunitaire combiné, neutropénie congénitale, défaut de l’axe IFNγ-IL12). Cependant certains patients développent des infections fongiques invasives sans immunodépression ou facteurs de risques identifiés. Nous avons donc émis l’hypothèse que ces infections avaient possiblement une origine génétique non identifiée. Au cours de ma thèse, j’ai étudié une cohorte de patients présentant des infections fongiques invasives sans facteur favorisant identifié afin de rechercher une étiologie génétique à ces infections. Le premier groupe de patients que j’ai étudié présentait une dermatophytose invasive ou dermatophytose profonde sans immunodépression. Contrairement à la dermatophytose superficielle, en général bénigne et fréquente dans la population générale; la dermatophytose profonde est une infection rare, invasive et sévère, dans laquelle les dermatophytes (qui sont des champignons filamenteux) envahissent les tissus dermiques et hypodermiques, les ganglions et parfois les organes profonds. Les patients que j’ai étudié étaient tous originaires d’Afrique du Nord, pour la plupart issus de familles consanguines, dont certains avec des cas multiples. Ces observations suggéraient une origine génétique de la dermatophytose profonde avec une hérédité probablement récessive. Au cours de ma thèse, j’ai étudié les caractéristiques cliniques, immunologiques et génétiques de 18 patients atteints d’une dermatophytose profonde, issus de neuf familles Marocaines, Algériennes, Tunisiennes ou Egyptiennes. En parallèle, j’ai étudié des patients ayant présenté des infections fongiques avec localisations cérébrales. L’une de ces patients a présenté des abcès cérébraux suite à une infection disséminée à Exophiala dermatitidis et trois patients ont développé des infections du système nerveux central à Candida spp.. Les infections invasives à Exophiala dermatitidis sont des infections rares, avec de fréquentes atteintes du système nerveux central, survenant majoritairement chez des patients sans déficit immunitaire identifié suggérant l’existence d’une origine génétique probable méconnue chez ces patients. Les candidoses invasives surviennent habituellement chez des patients neutropéniques, ayant récemment subi une intervention chirurgicale ou étant porteurs d’un cathéter intraveineux. Parmi les candidoses invasives, les localisations au système nerveux central sont rares, et classiquement rapportées chez des nouveau-nés prématurés ou suite à une intervention neurochirurgicale. J’ai par ailleurs étudié une patiente ayant développé des infections invasives des tissus sous-cutanés et des adénopathies dues à un champignon filamenteux. (...) / Invasive fungal diseases are a major health problem as they are severe infections complicated with high mortality rates and with rising incidence. Invasive fungal diseases occur mainly in patients with acquired immunodeficiencies, but also with primary immunodeficiencies (chronic granulomatous disease, defect in IFN-ϒ/IL-12 axis, congenital neutropenia). However, few patients develop invasive fungal disease without known risk factor. We therefore hypothesized that these infections probably have an unidentified genetic etiology. I studied a cohort of patients who developed invasive fungal diseases without risk factors and searched for a genetic etiology to their infections. The first group of patients presented with deep dermatophytosis without known immunodeficiency. Deep dermatophytosis is a rare, invasive and severe infection where dermatophytes invade dermis, hypodermis, lymph nodes and sometimes deep organs. I could study clinical, immunological and genetic characteristics of 18 patients from nine families who presented deep dermatophytosis. I also studied patients who developed central nervous system (CNS) fungal infections; one patient with CNS Exophiala dermatitidis infection and three patients with CNS Candida spp. infection. Invasive E. dermatitidis infections are rare, with frequent CNS location, mainly reported in patients without known immunodeficiencies, suggesting a potential unknown genetic etiology in these patients. CNS candidiasis are also rare infections usually occuring in preterm neonates or following neurosurgery. Based on literature data previously reporting a large consanguineous Iranian family with CARD9 deficiency that developed chronic mucocutaneous and central nervous system candidiasis; according to candidate gene approach, I sequenced CARD9 in all patients. CARD9 is an adaptor protein expressed by myeloid cells that signals downstream Dectin-1 and Dectin2 that are the main Pattern Recognotion Receptor implicated in antifungal immunity. I identified in all studied patients homozygous CARD9 mutations. Among 18 patients with deep dermatophytosis, 16 had homozygous nonsense Q289X and two homozygous missense R101C mutation in CARD9. I identified R18W, R35Q and R70W homozygous missense mutations in the patients who developed E. dermatitidis and two patients who developed CNS candidiasis, respectively. Transmission was autosomal recessive for all patients, except for the one with E. dermatitidis infection who had an uniparental disomy. In contrast with controls, CARD9 expression is abolished in Q289X, reduced in R70W and normal in R18W patients’ myeloid cells. CARD9 deficient patients whole blood and dendritic cells display a selective response defect to Candida albicans and Saccharomyces cerevisiae ; with IL-6 and TNF-α production impairment after Candida albicans and Saccharomyces cerevisiae stimulation. This defect can explain elective fungal susceptibility of CARD9 deficient patients to invasive fungal infections. This work evidenced that CARD9 deficiency was the main genetic etiology of deep dermatophytosis. It also could evidence that CARD9 deficiency is associated with Exophiala dermatitidis and Candida spp. CNS infections. This susceptibility is associated with proinflammatory cytokines defect by dendritic cells and whole blood to fungal agents. Various fungal clinical phenotypes in CARD9 deficient patients assess CARD9 central role in skin and central nervous system antifungal immunity.
5

Characterization of four septin genes, and detection of genetic interactions between WdCDC10 and chitin synthase genes during yeast budding in the polymorphic mold, Wangiella (Exophiala) dermatitidis

Park, Changwon 28 April 2015 (has links)
Septins are a highly conserved family of eukaryotic proteins having significant homology within and among species. In the budding yeast, Saccharomyces cerevisiae, a septin-based hierarchy of proteins is required to localize chitin in the bud neck prior to septum formation. However, this process has not been clarified in a filamentous, conidiogenous fungus capable of yeast growth, such as Wangiella dermatitidis, a polymorphic agent of human phaeohyphomycosis. Prior studies of this melanized mold showed that some chitin synthase mutants (wdchsΔ) have defects in yeast septum formation, suggesting that the septins of W. dermatitidis might functionally associate with some of its chitin synthases (WdChsp). To test this hypothesis, four vegetative septin homologs of S. cerevisiae were cloned from W. dermatitidis and designated WdCDC3, WdCDC10, WdCDC11, and WdCDC12. Of the four, only WdCDC3 functionally complemented completely a strain of S. cerevisiae with a ts mutation in the corresponding gene, although WdCDC12 did so partially. Functional characterizations by mutagenesis of the four W. dermatitidis septin genes revealed that resulting mutants (wdcdc[delta]) each had unique defects in yeast growth and morphology, indicating that each septin carried out a distinct function. Furthermore, when a wdcdc10[delta] mutation was introduced into five different wdchs[delta] strains, weak genetic interactions were detected between WdCDC10 and WdCHS3 and WdCHS4, and a strong interaction between and WdCHS5. Cytological studies showed that WdChs5p was mislocalized in some septin mutants, including wdcdc10[delta]. These results confirmed that in W. dermatitidis septins are important for proper cellular morphogenesis, cytokinesis, and especially septum formation through associations with some chitin synthases. / text
6

Characterization of genes involved in the synthesis of β(1→3) glucan, and investigation of genetic interactions among three Rho-type GTPase genes in the polymorphic fungus Wangiella (Exophiala) dematitidis

Guo, Pengfei, 1976- 23 March 2011 (has links)
Morphological transitions in Wangiella dermatitidis, a causative agent of human phaeohyphomycosis, influence virulence processes in this polymorphic fungus. My project first involved the cloning and characterizion of the β(1→3) glucan synthase gene WdFKS1, which encodes the enzyme's catalytic subunit, followed by cloning and characterizing the WdRHO1 gene, which encodes its regulatory subunit. To better understand the Rho-type GTPase-mediated regulation of cell polarity and its role in fungal morphological transitions, a homologue of WdRAC1 from a W. dermatitidis was subsequently identified by degenerate PCR and gene walking. Gene deletions of WdFKS1 and WdRHO1 in haploid W. dermatitidis were lethal, whereas the deletion of WdRAC1 was not. RNA interference on WdFKS1 mRNA expression resulted in incomplete septa and damaged cell wall integrity, as well as slow growth rate in W. dermatitidis. Overexpression studies, after site-specific integrations of WdRHO1 and WdRAC1 alleles under control of the glaA promoter into the nonessential WdPKS1 locus, showed the different alleles had different effects on the cell morphological development. For example, whereas overexpression of the wdrho1⁺ allele did not affect the growth rate of W. dermatitidis, the overexpression of wdrho1[superscript G14V], a constitutively active mutation, slowed growth and repressed true filamentous hyphal growth by promoting pseudohyphal growth. While the deletion of WdRAC1 did not affect growth, its loss retarded polarized hyphal growth in a hyphal-inducing minimal medium. Moreover, three new phenotypes of a previously derived WdCDC42 deletion mutant were discovered during this study: in the first, the wdcdc42[Delta] mutant displayed cell lysis when incubated in YPMaltose medium at 37°C; in the second, a dark budding neck abnormality was found after Calcoflour staining; and in the third, the wdcdc42[Delta] mutant displayed no branching during true hyphal growth. Interestingly, the overexpression of wdrac1[superscript G16V] complemented the second and the third phenotypes caused by the WdCDC42 deletion. In addition, the wdcdc42[Delta]/wdrac1[superscript G16V] double mutant unexpectedly displayed an interrupted carotenogenesis pathway. These results support that in W. dermatitidis, Rho-type GTPases play essential roles in growth rate determination and cellular morphogenesis, especially while producing polarized hyphal growth during its many morphological transitions. / text
7

Nanoemulsões de anfotericina B e itraconazol : avaliação da atividade antifúngica in vitro e in vivo em agentes da cromoblastomicose

Daboit, Tatiane Caroline January 2013 (has links)
Cromoblastomicose é uma micose crônica que acomete a pele e o tecido subcutâneo. Vários tratamentos têm sido utilizados, mas a eficácia é extremamente baixa, não permitindo eleger uma terapia de escolha. No presente trabalho foram realizados: I – ensaios de suscetibilidade in vitro de agentes da cromoblastomicose contra antifúngicos comerciais; II - caracterização molecular de amostras oriundas de casos clínicos, bem como a descrição destes casos; III - a produção e caracterização de duas nanoemulsões, uma de anfotericina B e uma de itraconazol produzidas pela técnica de homogeneização à alta pressão; IV - a avaliação da atividade antifúngica destas nanoemulsões in vitro e in vivo em agentes da cromoblastomicose; V - a verificação do nível de comprometimento renal e hepático causados pelas nanoemulsões; VI - a avaliação da toxicidade das formulações produzidas. De modo geral, os agentes da cromoblastomicose, apresentaram maior suscetibilidade à terbinafina e ao itraconazol, respectivamente. A combinação de anfotericina B e terbinafina foi sinérgica para quatro dos cinco grupos avaliados. Quanto aos casos clínicos, no primeiro foi identificada uma infecção por E. spinifera e no segundo uma por Fonsecaea monophora. As nanoemulsões foram elaboradas com composição passível de administração parenteral, uma de anfotericina B e uma de itraconazol, pelo método de homogeneização à alta pressão. Não foi possível determinar as CIMs da nanoemulsão de anfotericina B e Abelcet® in vitro, enquanto que a nanoemulsão de itraconazol apresentou CIMs muito semelhantes às do fármaco livre. Em modelo animal de cromoblastomicose, a nanoemulsão de anfotericina B foi mais ativa que o fármaco livre, Fungizone® e Abelcet®. A nanoemulsão de itraconazol também apresentou melhor atividade quando comparada com o fármaco livre. Os níveis de uréia foram mais elevados nos animais que receberam anfotericina B livre e Fungizone®. A enzima alanina aminotransferase foi encontrada em níveis menores nos animais tratados com a nanoemulsão de itraconazol do que naqueles que receberam itraconazol livre. A anfotericina B livre e Fungizone® causaram graves danos aos rins. Nos animais tratados com Abelcet® e com a nanoemulsão de anfotericina B foi possível verificar apenas necrose focal. Da mesma forma, a nanoemulsão de itraconazol protegeu os animais contra danos hepáticos quando comparada com o fármaco livre. Em relação aos ensaios de toxicidade, a anfotericina B foi citotóxica em concentrações a partir de 4μg/mL, sendo que com a nanoemulsão esta toxicidade não foi observada em concentrações mais elevadas. O itraconazol foi citotóxico, sendo que este efeito não foi visto com a nanoemulsão. É de extrema importância a avaliação da suscetibilidade dos agentes da cromoblastomicose a fim de orientar a clínica. A identificação molecular de agentes isolados de casos clínicos pode contribuir para delinear o perfil epidemiológico da doença. As nanoemulsões de anfotericina B e itraconazol apresentaram atividades superiores in vivo quando comparadas aos demais tratamentos e foram capazes de reduzir os efeitos adversos causados por estes antifúngicos. Através de ensaios in vitro foi confirmada a redução da citotoxidade do fármaco quando veiculado na nanoemulsão. Assim, as nanoemulsões produzidas poderiam ser alternativas terapêuticas para o tratamento da cromoblatomicose. / Chromoblastomycosis is a chronic mycosis that affects the skin and subcutaneous tissue. Various treatments have been used, but the efficacy is extremely low and does not allow choosing a therapy of choice. In the present work was performed: I - in vitro susceptibility testing for chromoblastomycosis agents against commercial antifungal; II - molecular characterization of samples from clinical cases as well as the description of these cases III - production and characterization of two nanoemulsions , one of amphotericin B and one of itraconazole, produced by high pressure homogenization technique; IV - assessing the in vitro and in vivo antifungal activity of these nanoemulsions against chromoblastomycosis agents; V - checking the level of impairment caused in the kidney and liver by nanoemulsions; VI - evaluation of toxicity of the formulations produced. In general, the chromoblastomycosis agents showed greater susceptibility to terbinafine and to itraconazole, respectively. The combination of amphotericin B and terbinafine was synergistic to four of the five groups. As for clinical cases, in the first was identified an infection by E. spinifera and in the second one by Fonsecaea monophora. The nanoemulsions were prepared with composition amenable of parenteral administration, one of amphotericin B and one of itraconazole, by the at high pressure homogenization method. Could not be determined the MIC of amphotericin B nanoemulsion and Abelcet® in vitro, while the itraconazole nanoemulsion showed MICs very similar to free drug. In a chromoblastomycosis animal model, the amphotericin B nanoemulsion was more active than free drug, Abelcet® and Fungizone®. The nanoemulsion of itraconazole also showed better activity compared to the free drug. Urea levels were higher in the animals receiving amphotericin B free and Fungizone®. The enzyme alanine aminotransferase was found in lower levels in animals treated with itraconazole nanoemulsion than in those who received itraconazole free. Amphotericin B free and Fungizone® caused severe damage to the kidneys. Already in animals treated with Abelcet® and the amphotericin B nanoemulsion was verified only focal necrosis. Likewise, the itraconazole nanoemulsion protected against liver damage when compared with the free drug. Regarding toxicity assays, amphotericin B was cytotoxic at concentrations from 4 μg/mL, while with the nanoemulsion this toxicity was not observed at higher concentrations. Itraconazole was cytotoxic, and this effect was not observed with the nanoemulsion. It is extremely important to evaluate the susceptibility of chromoblastomycosis agents to guide the clinic. Molecular identification of agents isolated from clinical cases can contribute to outline an epidemiological profile of the disease. The amphotericin B and itraconazole nanoemulsions showed higher activities in vivo when compared to other treatments and were able to reduce the adverse effects caused by these antifungals. Through in vitro assays were confirmed the reduction of the cytotoxicity of the drug when vehiculated in the nanoemulsion. Therefore, the nanoemulsions may be produced therapeutic alternatives for the chromoblastomycosis treatment.
8

Nanoemulsões de anfotericina B e itraconazol : avaliação da atividade antifúngica in vitro e in vivo em agentes da cromoblastomicose

Daboit, Tatiane Caroline January 2013 (has links)
Cromoblastomicose é uma micose crônica que acomete a pele e o tecido subcutâneo. Vários tratamentos têm sido utilizados, mas a eficácia é extremamente baixa, não permitindo eleger uma terapia de escolha. No presente trabalho foram realizados: I – ensaios de suscetibilidade in vitro de agentes da cromoblastomicose contra antifúngicos comerciais; II - caracterização molecular de amostras oriundas de casos clínicos, bem como a descrição destes casos; III - a produção e caracterização de duas nanoemulsões, uma de anfotericina B e uma de itraconazol produzidas pela técnica de homogeneização à alta pressão; IV - a avaliação da atividade antifúngica destas nanoemulsões in vitro e in vivo em agentes da cromoblastomicose; V - a verificação do nível de comprometimento renal e hepático causados pelas nanoemulsões; VI - a avaliação da toxicidade das formulações produzidas. De modo geral, os agentes da cromoblastomicose, apresentaram maior suscetibilidade à terbinafina e ao itraconazol, respectivamente. A combinação de anfotericina B e terbinafina foi sinérgica para quatro dos cinco grupos avaliados. Quanto aos casos clínicos, no primeiro foi identificada uma infecção por E. spinifera e no segundo uma por Fonsecaea monophora. As nanoemulsões foram elaboradas com composição passível de administração parenteral, uma de anfotericina B e uma de itraconazol, pelo método de homogeneização à alta pressão. Não foi possível determinar as CIMs da nanoemulsão de anfotericina B e Abelcet® in vitro, enquanto que a nanoemulsão de itraconazol apresentou CIMs muito semelhantes às do fármaco livre. Em modelo animal de cromoblastomicose, a nanoemulsão de anfotericina B foi mais ativa que o fármaco livre, Fungizone® e Abelcet®. A nanoemulsão de itraconazol também apresentou melhor atividade quando comparada com o fármaco livre. Os níveis de uréia foram mais elevados nos animais que receberam anfotericina B livre e Fungizone®. A enzima alanina aminotransferase foi encontrada em níveis menores nos animais tratados com a nanoemulsão de itraconazol do que naqueles que receberam itraconazol livre. A anfotericina B livre e Fungizone® causaram graves danos aos rins. Nos animais tratados com Abelcet® e com a nanoemulsão de anfotericina B foi possível verificar apenas necrose focal. Da mesma forma, a nanoemulsão de itraconazol protegeu os animais contra danos hepáticos quando comparada com o fármaco livre. Em relação aos ensaios de toxicidade, a anfotericina B foi citotóxica em concentrações a partir de 4μg/mL, sendo que com a nanoemulsão esta toxicidade não foi observada em concentrações mais elevadas. O itraconazol foi citotóxico, sendo que este efeito não foi visto com a nanoemulsão. É de extrema importância a avaliação da suscetibilidade dos agentes da cromoblastomicose a fim de orientar a clínica. A identificação molecular de agentes isolados de casos clínicos pode contribuir para delinear o perfil epidemiológico da doença. As nanoemulsões de anfotericina B e itraconazol apresentaram atividades superiores in vivo quando comparadas aos demais tratamentos e foram capazes de reduzir os efeitos adversos causados por estes antifúngicos. Através de ensaios in vitro foi confirmada a redução da citotoxidade do fármaco quando veiculado na nanoemulsão. Assim, as nanoemulsões produzidas poderiam ser alternativas terapêuticas para o tratamento da cromoblatomicose. / Chromoblastomycosis is a chronic mycosis that affects the skin and subcutaneous tissue. Various treatments have been used, but the efficacy is extremely low and does not allow choosing a therapy of choice. In the present work was performed: I - in vitro susceptibility testing for chromoblastomycosis agents against commercial antifungal; II - molecular characterization of samples from clinical cases as well as the description of these cases III - production and characterization of two nanoemulsions , one of amphotericin B and one of itraconazole, produced by high pressure homogenization technique; IV - assessing the in vitro and in vivo antifungal activity of these nanoemulsions against chromoblastomycosis agents; V - checking the level of impairment caused in the kidney and liver by nanoemulsions; VI - evaluation of toxicity of the formulations produced. In general, the chromoblastomycosis agents showed greater susceptibility to terbinafine and to itraconazole, respectively. The combination of amphotericin B and terbinafine was synergistic to four of the five groups. As for clinical cases, in the first was identified an infection by E. spinifera and in the second one by Fonsecaea monophora. The nanoemulsions were prepared with composition amenable of parenteral administration, one of amphotericin B and one of itraconazole, by the at high pressure homogenization method. Could not be determined the MIC of amphotericin B nanoemulsion and Abelcet® in vitro, while the itraconazole nanoemulsion showed MICs very similar to free drug. In a chromoblastomycosis animal model, the amphotericin B nanoemulsion was more active than free drug, Abelcet® and Fungizone®. The nanoemulsion of itraconazole also showed better activity compared to the free drug. Urea levels were higher in the animals receiving amphotericin B free and Fungizone®. The enzyme alanine aminotransferase was found in lower levels in animals treated with itraconazole nanoemulsion than in those who received itraconazole free. Amphotericin B free and Fungizone® caused severe damage to the kidneys. Already in animals treated with Abelcet® and the amphotericin B nanoemulsion was verified only focal necrosis. Likewise, the itraconazole nanoemulsion protected against liver damage when compared with the free drug. Regarding toxicity assays, amphotericin B was cytotoxic at concentrations from 4 μg/mL, while with the nanoemulsion this toxicity was not observed at higher concentrations. Itraconazole was cytotoxic, and this effect was not observed with the nanoemulsion. It is extremely important to evaluate the susceptibility of chromoblastomycosis agents to guide the clinic. Molecular identification of agents isolated from clinical cases can contribute to outline an epidemiological profile of the disease. The amphotericin B and itraconazole nanoemulsions showed higher activities in vivo when compared to other treatments and were able to reduce the adverse effects caused by these antifungals. Through in vitro assays were confirmed the reduction of the cytotoxicity of the drug when vehiculated in the nanoemulsion. Therefore, the nanoemulsions may be produced therapeutic alternatives for the chromoblastomycosis treatment.
9

Nanoemulsões de anfotericina B e itraconazol : avaliação da atividade antifúngica in vitro e in vivo em agentes da cromoblastomicose

Daboit, Tatiane Caroline January 2013 (has links)
Cromoblastomicose é uma micose crônica que acomete a pele e o tecido subcutâneo. Vários tratamentos têm sido utilizados, mas a eficácia é extremamente baixa, não permitindo eleger uma terapia de escolha. No presente trabalho foram realizados: I – ensaios de suscetibilidade in vitro de agentes da cromoblastomicose contra antifúngicos comerciais; II - caracterização molecular de amostras oriundas de casos clínicos, bem como a descrição destes casos; III - a produção e caracterização de duas nanoemulsões, uma de anfotericina B e uma de itraconazol produzidas pela técnica de homogeneização à alta pressão; IV - a avaliação da atividade antifúngica destas nanoemulsões in vitro e in vivo em agentes da cromoblastomicose; V - a verificação do nível de comprometimento renal e hepático causados pelas nanoemulsões; VI - a avaliação da toxicidade das formulações produzidas. De modo geral, os agentes da cromoblastomicose, apresentaram maior suscetibilidade à terbinafina e ao itraconazol, respectivamente. A combinação de anfotericina B e terbinafina foi sinérgica para quatro dos cinco grupos avaliados. Quanto aos casos clínicos, no primeiro foi identificada uma infecção por E. spinifera e no segundo uma por Fonsecaea monophora. As nanoemulsões foram elaboradas com composição passível de administração parenteral, uma de anfotericina B e uma de itraconazol, pelo método de homogeneização à alta pressão. Não foi possível determinar as CIMs da nanoemulsão de anfotericina B e Abelcet® in vitro, enquanto que a nanoemulsão de itraconazol apresentou CIMs muito semelhantes às do fármaco livre. Em modelo animal de cromoblastomicose, a nanoemulsão de anfotericina B foi mais ativa que o fármaco livre, Fungizone® e Abelcet®. A nanoemulsão de itraconazol também apresentou melhor atividade quando comparada com o fármaco livre. Os níveis de uréia foram mais elevados nos animais que receberam anfotericina B livre e Fungizone®. A enzima alanina aminotransferase foi encontrada em níveis menores nos animais tratados com a nanoemulsão de itraconazol do que naqueles que receberam itraconazol livre. A anfotericina B livre e Fungizone® causaram graves danos aos rins. Nos animais tratados com Abelcet® e com a nanoemulsão de anfotericina B foi possível verificar apenas necrose focal. Da mesma forma, a nanoemulsão de itraconazol protegeu os animais contra danos hepáticos quando comparada com o fármaco livre. Em relação aos ensaios de toxicidade, a anfotericina B foi citotóxica em concentrações a partir de 4μg/mL, sendo que com a nanoemulsão esta toxicidade não foi observada em concentrações mais elevadas. O itraconazol foi citotóxico, sendo que este efeito não foi visto com a nanoemulsão. É de extrema importância a avaliação da suscetibilidade dos agentes da cromoblastomicose a fim de orientar a clínica. A identificação molecular de agentes isolados de casos clínicos pode contribuir para delinear o perfil epidemiológico da doença. As nanoemulsões de anfotericina B e itraconazol apresentaram atividades superiores in vivo quando comparadas aos demais tratamentos e foram capazes de reduzir os efeitos adversos causados por estes antifúngicos. Através de ensaios in vitro foi confirmada a redução da citotoxidade do fármaco quando veiculado na nanoemulsão. Assim, as nanoemulsões produzidas poderiam ser alternativas terapêuticas para o tratamento da cromoblatomicose. / Chromoblastomycosis is a chronic mycosis that affects the skin and subcutaneous tissue. Various treatments have been used, but the efficacy is extremely low and does not allow choosing a therapy of choice. In the present work was performed: I - in vitro susceptibility testing for chromoblastomycosis agents against commercial antifungal; II - molecular characterization of samples from clinical cases as well as the description of these cases III - production and characterization of two nanoemulsions , one of amphotericin B and one of itraconazole, produced by high pressure homogenization technique; IV - assessing the in vitro and in vivo antifungal activity of these nanoemulsions against chromoblastomycosis agents; V - checking the level of impairment caused in the kidney and liver by nanoemulsions; VI - evaluation of toxicity of the formulations produced. In general, the chromoblastomycosis agents showed greater susceptibility to terbinafine and to itraconazole, respectively. The combination of amphotericin B and terbinafine was synergistic to four of the five groups. As for clinical cases, in the first was identified an infection by E. spinifera and in the second one by Fonsecaea monophora. The nanoemulsions were prepared with composition amenable of parenteral administration, one of amphotericin B and one of itraconazole, by the at high pressure homogenization method. Could not be determined the MIC of amphotericin B nanoemulsion and Abelcet® in vitro, while the itraconazole nanoemulsion showed MICs very similar to free drug. In a chromoblastomycosis animal model, the amphotericin B nanoemulsion was more active than free drug, Abelcet® and Fungizone®. The nanoemulsion of itraconazole also showed better activity compared to the free drug. Urea levels were higher in the animals receiving amphotericin B free and Fungizone®. The enzyme alanine aminotransferase was found in lower levels in animals treated with itraconazole nanoemulsion than in those who received itraconazole free. Amphotericin B free and Fungizone® caused severe damage to the kidneys. Already in animals treated with Abelcet® and the amphotericin B nanoemulsion was verified only focal necrosis. Likewise, the itraconazole nanoemulsion protected against liver damage when compared with the free drug. Regarding toxicity assays, amphotericin B was cytotoxic at concentrations from 4 μg/mL, while with the nanoemulsion this toxicity was not observed at higher concentrations. Itraconazole was cytotoxic, and this effect was not observed with the nanoemulsion. It is extremely important to evaluate the susceptibility of chromoblastomycosis agents to guide the clinic. Molecular identification of agents isolated from clinical cases can contribute to outline an epidemiological profile of the disease. The amphotericin B and itraconazole nanoemulsions showed higher activities in vivo when compared to other treatments and were able to reduce the adverse effects caused by these antifungals. Through in vitro assays were confirmed the reduction of the cytotoxicity of the drug when vehiculated in the nanoemulsion. Therefore, the nanoemulsions may be produced therapeutic alternatives for the chromoblastomycosis treatment.

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