57 research outputs found
Ecological study of Paracoccidioides brasiliensis in soil: growth ability, conidia production and molecular detection
<p>Abstract</p> <p>Background</p> <p><it>Paracoccidioides brasiliensis </it>ecology is not completely understood, although several pieces of evidence point to the soil as its most probable habitat. The present study aimed to investigate the fungal growth, conidia production and molecular pathogen detection in different soil conditions.</p> <p>Methods</p> <p>Soils samples of clayey, sandy and medium textures were collected from ground surface and the interior of armadillo burrows in a hyperendemic area of Paracoccidioidomycosis. <it>P</it>. <it>brasiliensis </it>was inoculated in soil with controlled humidity and in culture medium containing soil extracts. The molecular detection was carried out by Nested PCR, using panfungal and species specific primers from the ITS-5.8S rDNA region.</p> <p>Results</p> <p>The soil texture does not affect fungus development and the growth is more abundant on/in soil saturated with water. Some soil samples inhibited the development of <it>P. brasiliensis</it>, especially those that contain high values of Exchangeable Aluminum (H+Al) in their composition. Some isolates produced a large number of conidia, mainly in soil-extract agar medium. The molecular detection was positive only in samples collected from armadillo burrows, both in sandy and clayey soil.</p> <p>Conclusion</p> <p><it>P. brasiliensis </it>may grow and produce the infectious conidia in sandy and clayey soil, containing high water content, mainly in wild animal burrows, but without high values of H+Al.</p
Estudo da mcrobiota fúngica gastrintestinal de morcegos (Mammalia, Chiroptera) da região noroeste do estado de São Paulo: potencial zoonótico
Os morcegos são hospedeiros de uma rica diversidade de microrganismos. Muitos trabalhos apontam uma estreita ligação entre quirópteros e fungos com potencial patogênico, principalmente por habitarem ambientes como cavernas, grutas e ocos de árvores, favoráveis à manutenção e propagação dos fungos. O objetivo do trabalho foi estudar a microbiota fúngica gastrintestinal de morcegos. Das 98 amostras pertencentes a 11 espécies de morcegos procedentes de 15 cidades estudadas, 20% são da espécie Carollia perspicillata, 19% Artibeus lituratus, 17% Molossus rufus, 13% Glossophaga soricina, 9% Nyctinomops macrotis, 8% Molossus molossus, 7% Desmodus rotundus, 2% Lasiurus ega, e 1% Eptesicus furinalis, Myotis nigricans e Tadarida brasiliensis. O gênero Aspergillus sp. foi isolado de 29% das amostras, seguidos por 6% Microsporum sp. e Penicillium sp., 4% Tricophyton sp. e zigomicetos e 2% Fusarium sp. Das espécies de leveduras, 14% foram de Rhodotorula sp., 10% Candida sp. e 2% Cryptococcus sp., 22% dos isolados permaneceram sem identificação. Todos os 82 cultivos de vísceras foram negativos para Histoplasma capsulatum. Houve associação estatística significativa entre os resultados do cultivo microbiológico e as espécies de morcegos (p < 0,05). Concluímos que os morcegos podem atuar como agentes veiculadores de fungos com potencial patogênico, entretanto outros trabalhos devem ser realizados a fim de estabelecer estratégias que permitam identificar os principais fatores correlacionados com o crescimento e a disseminação dos microrganismos na natureza e qual a implicação dos quirópteros no ciclo epidemiológico.Bats are hosts of a rich diversity of microorganisms. Many studies indicate a close link between bats and fungi with pathogenic potential, especially for living in environments such as caves, caverns and hollow trees, favorable to the maintenance and spread of fungi. The objective was to study the gastrointestinal mycoflora of bats. Of the 98 samples belonging to 11 species of bats coming from 15 studied cities, 20% of the species were Carollia perspicillata, 19% Artibeus lituratus, 17% Molossus rufus, 13% Glossophaga soricina, 9% Nyctinomops macrotis, 8% Molossus molossus, 7% Desmodus rotundus, 2% Lasiurus ega and 1% Eptesicus furinalis, Myotis nigricans and Tadarida brasiliensis. The genus Aspergillus sp. was isolated from 29% of the samples, followed by 6% Microsporum sp. and Penicillium sp. 4% Trichophyton sp. and zygomycetes and 2% Fusarium sp. Of yeast species, 14% were from Rhodotorula sp., 10% Candida sp. and 2% Cryptococcus sp., 22% of isolates remained unidentified. All 82 cultures of organs were negative for Histoplasma capsulatum. There was a statistically significant association between the results of microbiological culture and bat species (p < 0.05). We conclude that the bats can act as disperser agents of fungi with pathogenic potential, although other studies should be performed to establish strategies to identify the main factors correlated with the growth and spread of microorganisms in nature and implication of bats in the epidemiological cycle
Photodynamic Therapy in Pythium insidiosum - An In Vitro Study of the Correlation of Sensitizer Localization and Cell Death
Pythiosis is an infectious disease caused by Pythium insidiosum, a fungus-like organism. Due to the lack of ergosterol on its cell membrane, antibiotic therapy is ineffective. The conventional treatment is surgery, but lesion recurrence is frequent, requiring several resections or limb amputation. Photodynamic therapy uses photo-activation of drugs and has the potential to be an attractive alternative option. The in vitro PDT response on the growing of Pythium insidiosum culture was investigated using three distinct photosensitizers: methylene blue, Photogem, and Photodithazine. The photosensitizer distribution in cell structures and the PDT response for incubation times of 30, 60, and 120 minutes were evaluated. Methylene blue did not penetrate in the pathogen's cell and consequently there was no PDT inactivation. Photogem showed heterogenous distribution in the hyphal structure with small concentration inside the cells. Porphyrin-PDT response was heterogenous, death and live cells were observed in the treated culture. After 48 hours, hyphae regrowth was observed. Photodithazine showed more homogenous distribution inside the cell and with the specific intracellular localization dependent on incubation time. Photodithazine first accumulates in intracellular vacuoles, and at incubation times of one hour, it is located at all cell membranes. Higher inhibition of the growing rates was achieved with Photodithazine -PDT, over 98%. Our results showed that the photosensitizers that cross more efficiently the Pythium insidiosum membranes are able to cause extensive damage to the organism under illumination and therefore, are the best options for clinical treatment.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Sporothrix schenckii sensu stricto Isolated from Soil in an Armadillo's Burrow
Sporotrichosis is a polymorphic disease of man and animals caused by traumatic implantation of propagules into the skin and subcutaneous tissue. Pathogenic species includes S. brasiliensis, S. schenckii, S. globosa and S. luriei. The disease is remarkable for its occurrence as sapronoses and/or zoonosis outbreaks in tropical and subtropical areas; although, the ecology of the clinical clade is still puzzling. Here, we describe an anamorphic Sporothrix strain isolated from soil in an armadillo's burrow, which was located in a hyper endemic area of Paracoccidioidomycosis in Brazil. This isolate was identified as S. schenckii sensu stricto (Clade IIa) based on morphological and physiological characteristics and phylogenetic analyses of calmodulin sequences. We then discuss the role of the nine-banded armadillo Dasypus novemcinctus as a natural carrier of Sporothrix propagules to better understand Sporothrix sources in nature and reveal essential aspects about the pathogen's eco-epidemiology.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Agarose cell block technique as a complementary method in the diagnosis of fungal osteomyelitis in a dog
A 7-year-old Labrador Retriever female dog presenting left forelimb lameness for one day was admitted to the Veterinary Hospital (UNESP-Botucatu) for clinical evaluation. Several tests, including blood and image analysis, microbiological culture and cytology of lytic areas of affected bone were made in order to establish a diagnosis. Serum biochemical profile revealed increased levels of liver enzymes, plasma globulin, creatine kinase (CK) and calcium. Hemogram revealed anemia and leukocytosis; left humerus image analysis revealed an osteolytic lesion and cytology revealed a suppurative periostitis. Differential diagnosis was a nonspecific infectious inflammatory process or osteosarcoma. Since it was not possible to achieve a definitive diagnosis and there was a highly suspicious for an infectious agent, an agarose cell block of the bone marrow fine-needle aspiration was made. The cytological examination of cell block presented similar findings as described previously. However, additional stains including periodic acid-Schiff (PAS) were positive for fungal hyphae, which rendered a diagnosis of fungal osteomyelitis due to Aspergillus spp. This case report illustrates an uncommon cause of osteomyelitis for breed that was diagnosed by an underused method in veterinary medicine
Chlorine incubation for 30 (A), 60 (B) and 120 minutes (C) in concentration of 150 µg/mL.
<p>Pathology morphology is preserved. Chlorine (red) is already present inside the cell surface after 30 minutes, and its distribution to all membranes is observed for longer incubation times.</p
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