ABSTRACT
The fungal strain Paracoccidioides brasiliensis remains viable inside of epithelial cells and can induce apoptosis in this population. However, until now, the molecules that participate in this process remained unknown. Thus, this study evaluated the contribution of two P. brasiliensis molecules, the 14-3-3 and glycoprotein of 43 kDa proteins, which had been previously described as extracellular matrix adhesins and apoptosis inductors in human pneumocytes. Accordingly, epithelial cells were treated with these molecules for different periods of time and the expression of the apoptosis regulating-proteins Bak, Bax, Bcl-2, p53 and caspases were evaluated by terminal deoxynucleotidyl transferase dUTP nick end labelling, flow cytometry and real-time polymerase chain reaction analysis. Our results demonstrated that treatment with these molecules induces apoptosis signalling in pulmonary epithelial cells, showing the same pattern of programmed cell-death as that observed during infection with P. brasiliensis. Thus, we could conclude that P. brasiliensis uses these molecules as virulence factors that participate not only in the fungal adhesion process to host cells, but also in other important cellular mechanisms such as apoptosis.
Subject(s)
Humans , Apoptosis , Antigens, Fungal/physiology , /physiology , Epithelial Cells/microbiology , Fungal Proteins/physiology , Glycoproteins/physiology , Paracoccidioides/physiology , Cell Line/microbiology , Flow Cytometry , In Situ Nick-End Labeling , Real-Time Polymerase Chain ReactionABSTRACT
A pesquisa avaliou a eficácia de ondas de alta frequência, no tratamento de onicomicose em 3 pacientes, durante 12 meses, através do exame clínico das unhas e exame micológico. O agente causal da micose nos três pacientes foi o dermatófito Trichophyton rubrum, e, após a aplicação da alta frequência, foi possível observar uma grande melhora no aspecto das unhas e uma inibição do crescimento em cultura, apesar do micológico direto se manter positivo. O estudo preliminar dos três casos demonstrou a atividade fungistática das ondas de alta frequência sendo um método promissor para ser utilizado, em associação com fármacos convencionais.
The research evaluated the efficacy of high frequency waves in the treatment of onychomycosis in three patients during twelve months through the clinical examination of nails and also through mycological examination. The causative agent of the mycosis, in the three patients, was the dermatophyte Trichophyton rubrum and after application of high frequency, it was possible to notice a great improvement in the appearance of nails and also growth inhibition in culture despite the fact that the mycological examination remained positive. The preliminary study of the three cases demonstrated that the fungistatic activity of high frequency waves is a promising method to be used in combination with conventional drugs.
Subject(s)
Humans , Onychomycosis/therapy , Ultrasonic Therapy/methods , Treatment Outcome , Trichophyton/isolation & purificationABSTRACT
JUSTIFICATIVA E OBJETIVOS: Dermatomicoses são doenças fúngicas que acometem a pele, unhas e cabelos de homens e animais, sendo altamente prevalentes na América Latina. O objetivo deste estudo foi identificar lesões características de micoses em frequentadores de Albergues e na população da periferia da cidade de Araraquara, SP. MÉTODO: Os voluntários que participaram da pesquisa foram atendidos na Casa Transitória e nas Unidades Básicas de Saúde (UBS) do município de Araraquara SP no ano de 2007. Foi realizada uma triagem de dermatomicoses, aquelas lesões que apresentavam características semelhantes foram submetidas à coleta, através de raspado de pele, unha, cabelo, sendo as amostras biológicas armazenadas em placas estéreis para o posterior processamento do material micológico. Após exame direto e cultura desses materiais, foram identificados os principais fungos responsáveis pelas lesões. RESULTADOS: Das 93 amostras coletadas, 40 (43%) foram positivas somente em cultura (sendo que 22 (23,6%) para dermatofitose, 15 (16,2%) para leveduras do gênero Candida e 3 (3,2%) para agentes de micoses superficiais), 15 (16,2%) amostras positivas para fungos, no exame direto não foi possível isolamento em cultura e 38 (40,8%) amostras negativas. O resultado mostrou que os pés foram as áreas anatômicas mais acometidas, a faixa etária entre 41e 50 anos foi a mais atingida e ambos os sexos apresentaram o mesmo número de casos de dermatomicose. CONCLUSÃO: Esse estudo permitiu conhecer a epidemiologia das dermatomicoses, embora essas desordens não sejam sérias em termos de mortalidade, lesões físicas e/ou psicológicas, elas têm significativa consequência clínica, com lesões crônicas, de difícil tratamento, contagiosas, além de problemas estéticos.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Candida albicans , Dermatomycoses , Epidermophyton , Microsporum , TrichophytonABSTRACT
Paracoccidioidomycosis presents a variety of clinical manifestations and Paracoccidioides brasiliensis can reach many tissues, most importantly the lungs. The ability of the pathogen to interact with host surface structures is essential to its virulence. The interaction between P. brasiliensis and epithelial cells has been studied, with particular emphasis on the induction of apoptosis. To investigate the expression of different apoptosis-inducing pathways in human A549 cells, we infected these cells with P. brasiliensis Pb18SP (subcultured) and 18R (recently isolated from cell culture and showing a high adhesion pattern) samples in vitro. The expressions of Bcl-2, Bak and caspase 3 were analysed by flow cytometry and DNA fragmentation using the TUNEL technique. Apoptosis of human A549 cells was induced by P. brasiliensis in a sample and time-dependent manner. Using an in vitro model, our data demonstrates that caspase 3, Bak, Bcl-2 and DNA fragmentation mediate P. brasiliensis-induced apoptosis in A549 cells. The overall mechanism is a complex process, which may involve several signal transduction pathways. These findings could partially explain the efficient behaviour of this fungus in promoting tissue infection and/or blood dissemination.