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1.
Vet Med Int ; 2024: 1267770, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716202

RESUMEN

Amazon River dolphins are an important flagship species in the Anavilhanas National Park, Brazil, where they interact with visitors. This study aimed to quantify and identify fungi isolated from dolphin skin and oral samples and their surrounding environment in this unique ecosystem. Samples were collected from three dolphins and water samples from Flutuante dos Botos and the Novo Airão city harbor. Fungi were isolated using culture media and identified through micromorphology assays and ITS region sequencing. Oral swab samples resulted in culture of Trichosporon montevideense and Exophiala dermatitidis. Skin samples from one dolphin revealed Toxicocladosporium irritans and Diaporthe lithocarpus. Water samples exhibited higher fungal counts and diversity, with Rhodotorula mucilaginosa, Exophiala dermatitidis, Penicillium citrinum, Fomitopsis meliae, and Nectria pseudotrichia identified at the collection site and Candida spencermartinsiae and Penicillium chermesinum at the city harbor. This study provides important insights into the fungal diversity associated with Amazon River dolphins and their environment, enhancing our understanding of the public health and ecological dynamics in the Anavilhanas National Park.

2.
Braz J Microbiol ; 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38368282

RESUMEN

Histoplasmosis is commonly observed in AIDS patients as a neglected opportunistic disease that has an important relationship with environmental factors. The present study described the clinical characteristics of HIV/AIDS patients diagnosed with disseminated histoplasmosis in a tertiary healthcare facility in Manaus, Amazonas, Brazil, and evaluated the patients' homes and urban environmental samples as a source of exposure to Histoplasma capsulatum. A review of medical records from 2017 to 2019 of patients with HIV/AIDS associated with histoplasmosis was carried out, as well as the collection of environmental samples in the homes of these patients. These samples were subjected to DNA extraction and then subjected to qPCR. A total of 62 patients diagnosed with HIV/AIDS and histoplasmosis were identified, which corresponds to 4.5% (n = 62/1372) of the HIV/AIDS cases detected in the period. Of these, 68% (n = 42/62) were male, with a mean age of 36 years and low education. In 47% (n = 29/62) of the cases, the diagnosis of HIV/AIDS and histoplasmosis occurred simultaneously. Mortality was 45% (n = 28/62), and 68% (n = 42/62) of these patients did not regularly use highly active antiretroviral therapy. The main symptoms found were respiratory, gastrointestinal, and weight loss, and in 81% (n = 50/62), the place of residence was in an urban area. A total of 57 environmental samples were analyzed, and the presence of Histoplasma capsulatum was not detected in any of the analyzed samples. There was a high mortality rate in the studied group of patients with AIDS and histoplasmosis. Most patients reported residing in urban areas of Manaus, with no history of travel to other areas previously known as being high risk for histoplasmosis.

3.
Artículo en Inglés | MEDLINE | ID: mdl-37738109

RESUMEN

Background: This study aimed at improving a real-time polymerase-chain-reaction (qPCR) assay for the detection of Histoplasma capsulatum, a fungal pathogen that can cause severe respiratory infections in humans, in clinical and soil samples. Methods: Primer and probes were in-silico designed, in-silico and in-vitro evaluated including clinical biopsy materials and finally subjected to a real-world application with collected soil samples. Results: Applying the qPCR assay with liver and lung biopsies from 71 patients each, including 59 patients infected with human immunodeficiency virus (HIV), as well as with Sabouraud (SAB) agar culture as the diagnostic reference standard, diagnostic accuracy of the qPCR assay of 100% (5/5) sensitivity and 96% (63/66) specificity for liver samples and 100% (4/4) sensitivity and 94% (63/67) specificity for the lung samples was recorded. When applying the assay with soil samples from caves near of Presidente Figueiredo city, Amazonas, Brazil, one sample from the Maroaga cave was confirmed as positive. Conclusions: The improved qPCR assessed in this study was successful in detecting H. capsulatum with high efficiency and accuracy in in-vitro evaluation, including the identification of the target pathogen in both clinical and environmental samples.

4.
Trop Med Int Health ; 27(4): 387-396, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35178835

RESUMEN

OBJECTIVES: In the state of Amazonas, northern Brazil, cryptococcosis is endemic, with a predominance of Cryptococcus neoformans in individuals with HIV/AIDS, and Cryptococcus gattii VGII in non-HIV individuals. This study analysed the clinical isolates and clinical-epidemiological characteristics of HIV/AIDS patients diagnosed with cryptococcosis in a tertiary healthcare facility in Manaus, Amazonas and investigated the presence of agents of cryptococcosis in environmental samples. METHODS: A survey was made of data from HIV/AIDS patients diagnosed with cryptococcosis between January 2017 and December 2019, and environmental samples were collected at the patients' and their neighbours' homes. The isolates were submitted to morphophysiological analysis and PCR-RFLP typing to determine the molecular types. RESULTS: Clinical-epidemiological characteristics of 55 patients and 75 clinical isolates were analysed. Neurocriptococcosis was the clinical form observed in 98.2% (n = 54/55) of patients. A total of 38.1% (n = 21/55) of patients died within 100 weeks, of which 21.8% (n = 12/55) died less than a month after the diagnosis of cryptococcosis. C. neoformans VNI (n = 68/75), C. neoformans VNII (n = 1/75), C. gattii VGI (n = 3/75) and C. gattii VGII (n = 3/75) were identified. Mixed infection was observed in two patients, one by C. neoformans VNI and VNII and the other by C. neoformans VNI and C. gattii VGI. Cryptococcus VNI was detected in three (n = 3/51) households, one of a patient (n = 1/17) and two households that neighbour patients' houses (n = 2/34). CONCLUSIONS: This study demonstrated the prevalence of C. neoformans VNI, which is a cause of cryptococcosis in patients with HIV/AIDS in the state of Amazonas, and revealed a greater diversity of molecular types affecting these patients in the region than in previous studies. In the studied group, a high mortality rate was observed, which reflects the importance of early diagnosis, and evidences cryptococcosis as an AIDS-defining disease and an important public health problem in the region. The home environment proved to be a potential source of infection/reinfection by C. neoformans VNI.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Criptococosis , Cryptococcus gattii , Cryptococcus neoformans , Brasil/epidemiología , Criptococosis/epidemiología , Genotipo , Humanos
5.
Ann Clin Microbiol Antimicrob ; 19(1): 20, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-32434527

RESUMEN

BACKGROUND: Cryptococcosis is a disease of wide geographic distribution. It is most critical when it affects immunocompromised patients, with AIDS, tuberculosis or other diseases that require prolonged hospitalization. METHODS: This study described a case report, molecular epidemiology, the phylogenetic relationship, along with antifungal susceptibility test of a new ST 623 of C. neoformans isolated in a patient with non-Hodgkin's Lymphoma, from Manaus, Brazil. RESULTS: The new C. neoformans was susceptible to all antifungal drugs tested. Our results showed that ST623 new clone has no evident evolutionary proximity to any other ST of the VNI subtype group identified in Brazil. CONCLUSIONS: In the context of phylogenetic analysis, this new genotype belongs to VNI subtype, and subsequencing complete genome studies are necessary to better understand the phylogenetic relationships amongst STs in this group.


Asunto(s)
Criptococosis/genética , Criptococosis/microbiología , Cryptococcus neoformans/clasificación , Cryptococcus neoformans/aislamiento & purificación , Anciano , Brasil , Criptococosis/diagnóstico , Criptococosis/tratamiento farmacológico , Cryptococcus neoformans/efectos de los fármacos , Resultado Fatal , Humanos , Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/microbiología , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Técnicas de Tipificación Micológica , Filogenia , Reacción en Cadena de la Polimerasa
6.
Acta sci., Biol. sci ; 39(1): 13-20, jan.-mar. 2017. tab, ilus
Artículo en Inglés | LILACS | ID: biblio-846673

RESUMEN

Endophytic bacteria isolated from Eichhornia crassipes (Mart) Solms., collected in oil contaminated wastewater of effluent generated by Petrobras refinery in Manaus were investigated to determine their potential for producing biosurfactants. Assay with 2.6-dichlorophenol indophenol (DCPIP) indicator to verify hydrocarbon biodegradation activity; oil emulsification test; drop-collapse method; surface tension and growth curve of biosurfactant production. The M87 Microbacterium sp. strain chosen for this work was identified by the sequencing of the rDNA region and the chemical characterization was performed by FTIR, UFLC/MS and 1H RMN techniques. The selected bacterial isolate provided 3g L-1 of biosurfactant, using diesel oil as sole carbon source, being efficient in biodegrading oil as demonstrated by the DCPIP test. Fractions obtained by column chromatography were efficient in reducing water surface tension around 40 mN m-1, especially fraction 1, which reduced it to 34.17 mN m-1. The different techniques of chemical analysis used for the identification of the biosurfactant isolate indicated that this is probably a long - chain fatty acid lipid type, which may be used in the future as both biosurfactant in decontamination processes of hydrocarbon-polluted areas or as bioemulsifier in countless processes, since it exhibited no toxicity as determined by Alamar Blue assay.


Foram investigadas bactérias endofíticas isoladas de Eichhornia crassipes (Mart.) Solms., coletadas em águas contaminadas com resíduos de petróleo em um afluente da refinaria da Petrobrás/Manaus, para avaliação da produção de biossurfactantes. Para selecionar o micro-organismos à produção e caracterização de biossurfactantes, foram realizados os seguintes testes: a descoloração do indicador 2,6 indofenol (DCPIP), emulsificação do diesel, colapso da gota, tensão superficial e curva de produção. A caracterização química foi realizada por meio das técnicas de FT-IR, UFLC/MS e RMN1H. A bactéria M87 Microbacterium neste estudo, foi identificada pelo sequenciamento da região rDNA e produziu 3g L-1 de biossurfactantes utilizando o diesel como fonte de carbono, mostrando-se eficiente na ação biodegradadora do petróleo, por meio do teste de Indofenol (DCPIP). As frações obtidas, mostraram-se eficazes na redução da tensão superficial da água abaixo de 40 mN m-1, com destaque para a fração 1 que reduziu a tensão superficial para 34,17 mN m-1. Pelas análises química utilizadas, pode-se inferir que, provavelmente, se trata de um ácido graxo de cadeia longa, que pode ser utilizado futuramente tanto como biossurfactante em processos de descontaminação de ambientes impactados por hidrocarbonetos, assim como bioemulsificante em inúmeros processos uma vez que não apresentou toxicidade por meio do teste realizado.


Asunto(s)
Biodegradación Ambiental , Eichhornia , Petróleo , Residuos
7.
Mycoses ; 59(8): 509-15, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27005969

RESUMEN

Cryptococcus neoformans and Cryptococcus gattii are the main causative agents of cryptococcosis, a systemic fungal disease that affects internal organs and skin, and which is acquired by inhalation of spores or encapsulated yeasts. It is currently known that the C. neoformans/C. gattii species complex has a worldwide distribution, however, some molecular types seem to prevail in certain regions. Few environmental studies of Cryptococcus have been conducted in the Brazilian Amazon. This is the first ecological study of the pathogenic fungi C. neoformans/C. gattii species complex in the urban area of Manaus, Amazonas, Brazil. A total of 506 samples from pigeon droppings (n = 191), captive bird droppings (n = 60) and tree hollows (n = 255) were collected from June 2012 to January 2014 at schools and public buildings, squares, pet shops, households, the zoo and the bus station. Samples were plated on niger seed agar (NSA) medium supplemented with chloramphenicol and incubated at 25°C for 5 days. Dark-brown colonies were isolated and tested for thermotolerance at 37°C, cycloheximide resistance and growth on canavanine-glycine-bromothymol blue agar. Molecular typing was done by PCR-RFLP. Susceptibility to the antifungal drugs amphotericin B, fluconazole, itraconazole and ketoconazole was tested using Etest(®) strips. In total, 13 positive samples were obtained: one tree hollow (C. gattiiVGII), nine pigeon droppings (C. neoformansVNI) and three captive bird droppings (C. neoformansVNI). The environmental cryptococcal isolates found in this study were of the same molecular types as those responsible for infections in Manaus.


Asunto(s)
Cryptococcus gattii/genética , Cryptococcus gattii/aislamiento & purificación , Cryptococcus neoformans/genética , Cryptococcus neoformans/aislamiento & purificación , Microbiología Ambiental , Tipificación Molecular/métodos , Anfotericina B/farmacología , Animales , Antifúngicos/farmacología , Aves/microbiología , Brasil , Criptococosis/microbiología , Cryptococcus gattii/clasificación , Cryptococcus gattii/patogenicidad , Cryptococcus neoformans/clasificación , Cryptococcus neoformans/patogenicidad , Reservorios de Enfermedades/microbiología , Heces/microbiología , Fluconazol/farmacología , Humanos , Itraconazol/farmacología , Cetoconazol/farmacología , Técnicas de Tipificación Micológica/métodos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Árboles/microbiología
8.
Braz. arch. biol. technol ; 57(1): 138-144, Jan.-Feb. 2014. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-702580

RESUMEN

Two methods were used to make crude preparations of surface-active compounds (SACs) produced by Gordonia amicalis grown on the medium containing 1% diesel oil. Using a 2:1 (v/v) solution of chloroform:methanol for extraction, Type I SACs were isolated and shown to produce oil in water (O/W) emulsions. Type II SACs were isolated by precipitation with ammonium sulfate and produced predominantly water in oil emulsions (W/O). The crude Type I and II preparations were able to produce a significant reduction in the surface tension of water; however, the crude Type II preparation had 10-25 fold higher emulsification activity than the Type I preparation. Both SAC preparations were analyzed by the TLC and each produced two distinct bands with Rf 0.44 and 0.62 and Rf 0.52 and 0.62, respectively. The partially purified SACs were characterized by the ESI(+)-MS, FT-IR and NMR. In each one of these fractions, a mixture of 10 oligomers was found consisting of a series of compounds, with masses from 502 to 899, differing in molecular mass by a repeating unit of 44 Daltons. The mass spectra of these compounds did not appear to match other known biosurfactants and could represent a novel class of these compounds.

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