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1.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688756

RESUMO

This study evaluated in-vitro action of a new molecule, the polypyrrole nanoparticles (Ppy-NP), against Pythium insidiosum isolates using M38-A2/CLSI; the minimal inhibitory (MIC) and minimal oomicidal (MOC) concentrations were also determined. Additionally, changes in the hyphae wall of P. insidiosum CBS 575.85 treated with Ppy-NP were evaluated by scanning electron microscopy (SEM). The MIC100 and MOC for all isolates ranged from 8 to 32 µg mL-1, and the MIC90 and MIC50 were 16 µg mL-1. The SEM showed structural damage to the hyphae of P. insidisoum treated with Ppy-NP, as hyphae surfaces with less turgidity were found, thereby showing scaling and ruptures compared to the control (untreated hyphae). Our findings highlighted the anti-P. insidiosum properties of Ppy-NP proved to be a promising candidate for research using pythiosis experimental models.


Assuntos
Nanopartículas , Pythium , Polímeros , Pirróis
2.
Med Mycol ; 60(12)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36441020

RESUMO

Brain, lungs, and intestines of Columba livia captured in Brazil were analyzed for research on Tremellomycetes. Mycological culture presented the growth of colonies suggestive of Cryptococcus spp. in 11.60% (13/112) of the samples. Microscopy revealed capsulated yeast cells. Molecular analysis evidenced Papiliotrema flavescens, Naganishia diffluens, Filobasidium magnum, and Naganishia randhawae. Thermotolerance of Tremellomycetes isolates from brain and lung (n = 10) evidenced cell growth and viability at 37 °C. At 42 °C/24 h, these isolates showed viability, except for one P. flavescens isolate. Here, we report the first isolation of Tremellomycetes species from the brain and lungs of a healthy C. livia.


The study reported the first isolation of Tremellomycetes species, including P. flavescens, N. diffluens, F. magnum, and N. randhawae from the organs of domestic pigeons. All isolates expressed important virulence factors such as capsule and thermotolerance, indicating their pathogenic potential.


Assuntos
Columbidae , Cryptococcus , Animais , Leveduras , Brasil
3.
Braz J Microbiol ; 53(1): 509-512, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35018604

RESUMO

We investigated the anti-Pythium insidiosum activity of the antimicrobial peptides (AMPs) MSI-78, LL-37, and magainin-2. To detect the minimum inhibitory concentration (MIC), fourteen clinical strains were incubated with the AMPs following the CLSI M38-A2 protocol. All three AMPs showed antimicrobial activity with an MIC range of 20-80 mg/L against all strains. We concluded that the evaluated AMPs have great potential as anti-Pythium insidiosum agents, and their activity deserves to be more explored in further research. Antimicrobial peptides were tested against Pythium insidiosum, a microorganism that causes a difficult-to-treat disease in animals and humans. These peptides have been shown to be able to kill P. insidiosum and may be candidates for use in the treatment of this infection.


Assuntos
Pythium , Animais , Peptídeos Catiônicos Antimicrobianos , Peptídeos Antimicrobianos , Humanos , Magaininas , Testes de Sensibilidade Microbiana
4.
Braz J Microbiol ; 53(1): 171-177, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34735710

RESUMO

We investigated the antibacterial activity of the antimicrobial peptides h-Lf1-11, MSI-78, LL-37, fengycin 2B, and magainin-2. The minimum inhibitory concentration (MIC) was determined by microdilution technique according to CLSI (M07-A9, 2012) against Escherichia coli, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, carbapenem-resistant Klebsiella pneumoniae, and Acinetobacter baumannii. The MSI-78 showed potent bactericidal activity with MIC range of 1.25-40 mg/L against all bacterial strains. The h-Lf1-11, magainin-2, and LL-37 exhibited moderate activity (MIC range of 40-160, 80-160, and 40-160 mg/L, respectively) while the fengycin 2B did not show significant activity against all bacterial strains tested. These results revealed that MSI-78, h-Lf1-11, magainin-2, and LL-37 have great potential as antibacterial agents and their activity deserves to be more explored in further studies for the treatment of antibiotic-resistant bacteria.


Assuntos
Antibacterianos/farmacologia , Peptídeos Antimicrobianos/farmacologia , Bactérias/efeitos dos fármacos , Lipopeptídeos/farmacologia , Magaininas/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana
5.
J Mycol Med ; 31(2): 101119, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33626413

RESUMO

Fusarium infections have been associated with high mortality rates due to the lack of definition of an ideal treatment strategy. Antimicrobial peptides (AMPs) have potential antifungal activity. Therefore, investigating the in vitro activity of these molecules alone and in association with conventional antifungals against clinical isolates of Fusarium was the aim of this study. Fusarium solani (n=10) strains were tested against the AMPs, MSI-78, h-Lf1-11 and cecropin B in accordance with CLSI protocol. Further, a checkerboard assay for its combination with amphotericin B or voriconazole, was carried out. MSI-78, h-Lf1-11 and cecropin B exhibited antifungal activity against F. solani strains tested with MICs ranging from 20 to 320mg/L. Satisfactory percentage of synergism was demonstrated for all evaluated combinations, ranging from 70 to 100%. The use of AMPs combined with amphotericin B and voriconazole antifungals has great synergistic potential and deserve to be evaluated in murine models of fusariosis.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Fusarium/efeitos dos fármacos , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Voriconazol/farmacologia , Combinação de Medicamentos , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana , Proteínas Citotóxicas Formadoras de Poros/classificação
6.
Med Mycol ; 59(1): 67-73, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-32400872

RESUMO

Pythium insidiosum infections have been widely studied in an attempt to develop an effective therapeutic protocol for the treatment of human and animal pythiosis. Several antifungal agents are still prescribed against this oomycete, although they present contradictory results. To evaluate the susceptibility profile and to verify the morphological alterations in P. insidiosum isolates treated with amorolfine hydrochloride and azithromycin, alone or in combination. Susceptibility tests for P. insidiosum isolates (n = 20) against amorolfine hydrochloride (AMR) and azithromycin (AZM) were performed according to Clinical and Laboratory Standards Institutes (CLSI) protocol M38-A2. Combinations of both drugs were evaluated using the checkerboard microdilution method. Additionally, transmission and scanning electron microscopy were performed in order to verify the morphological alterations in P. insidiosum isolates in response to these drugs. All P. insidiosum isolates had a minimum inhibitory concentration (MIC) ranging from 16 to 64 mg/l and 8 to 64 mg/l for amorolfine hydrochloride and azithromycin, respectively. Synergistic interactions between the drugs were not observed, with antagonism in 59.8% of isolates, and indifferent interactions in 36.2%. Electron microscopy showed changes in the surface of P. insidiosum hyphae, disorganization of intracellular organelles, and changes in the plasma membrane and cell wall of oomycetes treated with the drugs. This is the first study to demonstrate in vitro anti-P. insidiosum effect of amorolfine hydrochloride. These results indicate the therapeutic potential of this drug against cutaneous and subcutaneous forms of pythiosis, but further studies are necessary to confirm this potential.


Assuntos
Antifúngicos/farmacologia , Azitromicina/farmacologia , Testes de Sensibilidade Microbiana/veterinária , Morfolinas/farmacologia , Pitiose/tratamento farmacológico , Pythium/efeitos dos fármacos , Animais , Antifúngicos/uso terapêutico , Azitromicina/uso terapêutico , Modelos Animais de Doenças , Cães , Cavalos , Humanos , Morfolinas/uso terapêutico
7.
Mycoses ; 63(4): 395-406, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32012366

RESUMO

BACKGROUND: The evolution of pathogenic mechanisms is a major challenge, which requires a thorough comprehension of the phylogenetic relationships of pathogens. Peronosporaleans encompasses a heterogeneous group of oomycetes that includes some animal/human pathogens, like Pythium insidiosum. OBJECTIVE: We analysed here the phylogenetic positioning and other evolutionary aspects related to this species and other peronosporaleans, using a multi-locus approach with one mitochondrial and three nuclear genes. METHODOLOGY: Phylogenetic patterns of 55 oomycetes were inferred by maximum likelihood and Bayesian analysis, and a relaxed molecular clock method was applied to infer the divergence time of some peronosporaleans branches. RESULTS: Pythium insidiosum was monophyletic with a major and polytomous clade of American isolates; however, Pythium spp. was found to be paraphyletic with Phytopythium sp. and Phytophthora spp. In general, peronosporaleans subdivided into four lineages, one of which evidenced a close relationship of P insidiosum, P aphanidermatum and P arrhenomanes. This lineage diverged about 63 million years ago (Mya), whereas P insidiosum diversified at approximately 24 Mya. The divergence of American and Thai isolates seems to have occurred at approximately 17 Mya, with further American diversification at 2.4 Mya. CONCLUSION: Overall, this study clarifies the phylogenetic relationships of P insidiosum regarding other peronosporaleans in a multi-locus perspective, despite previous claims that phylogenomic analyses are needed to accurately infer the patterns and processes related to the evolution of different lineages in this group. Additionally, this is the first time that a molecular clock was applied to study the evolution of P insidiosum.


Assuntos
Evolução Molecular , Oomicetos/classificação , Filogenia , Pythium , Animais , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes Mitocondriais , Phytophthora/classificação , Pythium/classificação , Pythium/isolamento & purificação , RNA Ribossômico/genética
8.
Mycoses ; 62(5): 428-433, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30784136

RESUMO

This study evaluated the in vitro susceptibility of Trichosporon asahii strains to diphenyl diselenide (DPDS) and ebselen (EBS) alone and in combination with amphotericin B (AMB), fluconazole (FCZ), itraconazole (ITZ) and caspofungin (CAS) using the microdilution method. EBS showed in vitro activity against T asahii strains with minimal inhibitory concentration (MIC) ranged from 0.25 to 8.0 µg/mL. For DPDS, the MIC ranged from 8.0 to 64 µg/mL. The combinations demonstrating the greatest synergism rate against fluconazole-resistant T asahii strains were the following: CAS + DPDS (96.67%), AMB + DPDS (93.33%), FCZ + DPDS (86.67%) and ITZ + DPDS (83.33%). The combinations AMB + DPDS and AMB + EBS exhibited the highest synergism rate against the fluconazole-susceptible (FS) T asahii strains (90%). Antagonism was observed in the following combinations: FCZ + EBS (80%) and FCZ + DPDS (13.33%) against the FS strains, and ITZ + EBS (20%) against the FR strains. Our findings suggest that the antimicrobial activity of DPDS and EBS against T. asahii and its use as an adjuvant therapy with antifungal agents warrant in vivo experimental investigation.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Derivados de Benzeno/farmacologia , Agonismo de Drogas , Sinergismo Farmacológico , Compostos Organosselênicos/farmacologia , Trichosporon/efeitos dos fármacos , Isoindóis , Testes de Sensibilidade Microbiana
9.
Med Mycol ; 57(7): 807-812, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30260397

RESUMO

The oomycetous pathogen Pythium insidiosum is the causative agent of pythiosis, a life-threatening disease that affects animals and humans. This infectious disease is difficult to treat, and early and accurate diagnosis is critical for effective treatment. In this sense, this study aimed to evaluate the intradermal (ID) injection of P. insidiosum protein antigens (PiPA) for the diagnosis and treatment of pythiosis using an experimental model. For diagnostic purposes, PiPA were injected by the ID route in the following groups of rabbits: (a) control; (b) previously immunized with PiPA injected by the subcutaneous (SC) route; and (c) infected with P. insidiosum zoospores. For treatment purposes, rabbits with pythiosis were also treated with PiPA by the ID or SC routes. Mean induration sizes were different at 24 h and 72 h readings when compared to the control group. Sensitivity of the protocol was 100% at 24 h and 80% at 72 h, with 100% specificity in both readings. PiPA treatment using ID or SC routes did not result in significant differences in lesion sizes and cure rates; however, serum levels of interferon-gamma were higher in SC route. This study demonstrates the applicability of PiPA ID for diagnosis and treatment of pythiosis in an experimental model.


Assuntos
Antígenos/administração & dosagem , Pitiose/diagnóstico , Pitiose/terapia , Pythium/química , Animais , Antígenos/imunologia , Citocinas/sangue , Modelos Animais de Doenças , Injeções Intradérmicas , Interferon gama/sangue , Pythium/imunologia , Coelhos
10.
Artigo em Inglês | MEDLINE | ID: mdl-30373795

RESUMO

We evaluated the efficacy of azithromycin (50 mg/kg, every 12 h [q12h] orally) and miltefosine (25 mg/kg, q24h orally) treatments in an experimental model of vascular/disseminated pythiosis in immunosuppressed mice. Azithromycin was the only treatment able to reduce mortality. The histopathological findings showed acute vascular inflammation, pathogen dissemination, necrotizing myositis, neuritis, and arteritis. The results suggest that azithromycin, but not miltefosine, may have clinical relevance in the treatment of vascular/disseminated pythiosis.


Assuntos
Antiprotozoários/uso terapêutico , Azitromicina/uso terapêutico , Fosforilcolina/análogos & derivados , Pitiose/tratamento farmacológico , Pythium/efeitos dos fármacos , Animais , Hospedeiro Imunocomprometido/imunologia , Camundongos , Fosforilcolina/uso terapêutico , Pitiose/parasitologia
11.
Ciênc. rural (Online) ; 49(1): e20180744, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1045237

RESUMO

ABSTRACT: We aimed to genotype the South American clinical isolates of Pythium insidiosum using the single nucleotide polymorphisms (SNP) of the ribosomal DNA sequences (rDNA). Previously, an SNP-based multiplex-PCR was able to distinguish three different clades of P. insidiosum isolates. Thus, we used this assay to evaluate South American clinical isolates of P. insidiosum (n=32), standard strains from Costa Rica (n=4), Thailand (n=3), Japan (n=1), and India (n=1), a standard strain of Pythium aphanidermatum, and Brazilian environmental isolates of Pythium torulosum, Pythium rhizo-oryzae and Pythium pachycaule voucher (n=3). It was possible to allocate each American P. insidiosum isolate to clade I, the isolates of India, Japan, and Thailand to clade II, and the Thai isolate to clade III. P. aphanidermatum, P.torulosum, P.rhizo-oryzae and P.pachycaule voucher isolates were not amplified. For the first time, a P. insidiosum isolate from Uruguay, South America, was included in molecular analyzes. By SNP-based multiplex-PCR, it was possible to perform the identification and genotyping of the South American isolates of P. insidiosum, demonstrating similar genetic characteristics of these isolates.


RESUMO: O objetivo deste estudo foi genotipar isolados clínicos de Pythium insidiosum da América do Sul utilizando polimorfismos de nucleotídeo único (SNP) de sequências de rDNA. Anteriormente, um multiplex-PCR baseado em SNP foi capaz de distinguir P. insidiosum em três diferentes clados. Dessa forma, utilizamos este método para avaliar isolados clínicos de P. insidiosum da América do Sul (n=32), cepas padrão da Costa Rica (n=4), Tailândia (n=3), Japão (n=1) e Índia (n=1), uma cepa padrão de Pythium aphanidermatum e isolados ambientais brasileiros de Pythium torulosum; Pythium rhizo-oryzae e Pythium pachycaule voucher (n=3). Os isolados analisados foram alocados aos clados: I (americanos), II (isolados da Índia, Japão e Tailândia), e III (um isolado tailandês). P. aphanidermatum, P.torulosum, P.rhizo-oryzae e P.pachycaule voucher não foram amplificados. Pela primeira vez, um isolado de P. insidiosum do Uruguai foi incluído em análises moleculares. Através da multiplex-PCR baseada em SNP, foi possível realizar a identificação e genotipagem dos isolados sul-americanos de P. insidiosum, demonstrando características genéticas semelhantes entre esses isolados.

12.
Transbound Emerg Dis ; 65(6): 1671-1679, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29920968

RESUMO

Pythium insidiosum is a widespread pathogen that causes pythiosis, a disease with severe health consequences in horses and humans worldwide. Latin America hosts one of the largest, but scattered, horse herds, making it critical to identify areas at high risk of pythiosis transmission to help guide surveillance in areas with disease transmission risk. We utilized ecological niche modelling and epidemiological data to reconstruct the ecological conditions for pathogen circulation to identify areas with potential risk of pythiosis in Brazil and Uruguay. We surveyed 338 horse farm locations in southern Brazil and reconstructed the landscape conditions where the disease is endemic, based on the association between high-resolution satellite imagery and P. insidiosum serology. The final model was projected to the entire Brazil-Uruguay border region to predict areas at risk of disease transmission. We detected 66 seropositive farms and risk of infection in areas with low vegetation and low temperatures. There was a significant difference between seropositive and seronegative locations, mainly during the summer, suggesting that P. insidiosum circulates under specific landscape conditions. Areas that were unsuitable for P. insidiosum circulation were clustered in the central, north-eastern, and north-western regions of the study area. Our findings suggest that P. insidiosum is a generalist pathogen that has the potential to circulate across broad areas in Uruguay and Rio Grande do Sul in Brazil. The risk maps generated may help stakeholders with disease prevention, as well as highlight pythiosis as a potential transboundary disease with economic and public health importance.


Assuntos
Doenças dos Cavalos/epidemiologia , Pitiose/microbiologia , Pythium/isolamento & purificação , Animais , Anticorpos Antifúngicos/sangue , Brasil/epidemiologia , Doenças dos Cavalos/microbiologia , Cavalos , Humanos , Pitiose/epidemiologia , Pythium/patogenicidade , Uruguai/epidemiologia
13.
Diagn Microbiol Infect Dis ; 90(1): 40-43, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29126660

RESUMO

Posaconazole (PSC) in combination with anidulafungin (AFG) was evaluated in a murine model of pulmonary aspergillosis. Immunosuppressed animals were infected via the nasal cavity with 2 different A. fumigatus strains. The animals received PSC (oral, 20mg/kg per day) and/or AFG (i.p., 10mg/kg per day) for 7days. On Day 8, the mice were euthanized and fungal burdens were determined from the lungs. Survival curves were constructed for mortality analysis. Compared to untreated groups, groups singly treated with PSC or AFG showed a reduced fungal burden in the lungs (P=0.0001-0.006) and prevention of mortality (66.66-83.33% of survival). Combination treatment with PSC and AFG significantly reduced the fungal burden (or sterilized the lungs) compared to the findings in the untreated and monotherapy groups and improved the survival rate to 100%. The PSC and AFG combination therapy was highly effective and should be evaluated in larger-scale experiments.


Assuntos
Antifúngicos/uso terapêutico , Aspergillus fumigatus/efeitos dos fármacos , Equinocandinas/uso terapêutico , Aspergilose Pulmonar/tratamento farmacológico , Triazóis/uso terapêutico , Anidulafungina , Animais , Aspergillus fumigatus/isolamento & purificação , Modelos Animais de Doenças , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Aspergilose Pulmonar/microbiologia , Resultado do Tratamento
14.
Int J Antimicrob Agents ; 51(5): 784-788, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29127050

RESUMO

The aim of this study was to evaluate the susceptibility of 20 clinical isolates of Fusarium spp. to classic antifungals [amphotericin B (AmB), itraconazole (ITR), voriconazole (VRC) and caspofungin (CAS)] and to non-antifungal agents [amiodarone (AMD), doxycycline (DOX) and moxifloxacin (MFX)] by the broth microdilution method. Combinations between these antifungal and non-antifungal agents were also evaluated to determine the fractional inhibitory concentration indices using the chequerboard technique. Synergistic interactions were observed for the following combinations (% synergism): AMD + VRC, 80%; MFX + AmB, 75%; AMD + AmB, 65%; DOX + VRC, 60%; MFX + VRC, 55%; DOX + AmB, 50%; and AMD + CAS, 30%. Synergism was not observed for associations with ITR. Antagonism was not seen in any combination. These findings suggest that the combinations of AMD, DOX or MFX with AmB or VRC to have potential for future in vivo investigations.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Fusarium/efeitos dos fármacos , Anfotericina B/farmacologia , Caspofungina , Sinergismo Farmacológico , Quimioterapia Combinada , Equinocandinas/farmacologia , Humanos , Itraconazol/farmacologia , Lipopeptídeos/farmacologia , Testes de Sensibilidade Microbiana , Voriconazol/farmacologia
15.
Pesqui. vet. bras ; 37(5): 459-464, maio 2017. ilus, mapas, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-895441

RESUMO

Foram coletadas 186 amostras de água de ambientes pantanosos em 13 municípios das regiões Sul, Central e Oeste do Rio Grande do Sul, Brasil, com o objetivo de isolar e caracterizar espécies de Pythium e avaliar a sua patogenicidade empregando coelhos como modelo experimental. Em 11,8% (n=22) das águas coletadas foram isoladas diferentes espécies de Pythium incluindo: P. insidiosum (n=1), P. catenulatum (n=3), P. pachycaule voucher (n=1), P. rhizo-oryzae (n=3), P. torulosum (n=4) e Pythium spp. (n=10). Zoósporos desses micro-organismos foram produzidos in vitro e inoculados por via subcutânea em coelhos, os quais foram avaliados durante 45 dias. Dentre os oomicetos testados, apenas P. insidiosum evidenciou patogenicidade, causando pitiose no modelo experimental, evidenciando que, em nossas condições, apenas esta espécie de Pythium é patógena para mamíferos.(AU)


One hundred and eighty-six water samples from swampy areas were collected in 13 municipalities of South, Central and West regions of Rio Grande do Sul, Brazil, in order to isolate and characterize Pythium species and assess their pathogenicity using rabbits as experimental model. Different Pythium species were isolated from 22 (11.8%) water samples, including P. insidiosum (n=1), P. catenulatum (n=3), P. pachycaule voucher (n=1), P. rhizo-oryzae (n=3), P. torulosum (n=4) e Pythium spp. (n=10). Zoospores of these microorganisms were produced in vitro and inoculated subcutaneously into rabbits, which were assessed over 45 days. Only P. insidiosum showed pathogenicity, causing pythiosis in the experimental model.(AU)


Assuntos
Animais , Coelhos , Pythium/isolamento & purificação , Virulência , Modelos Animais , Pitiose , Água Doce/microbiologia
16.
Med Mycol ; 55(6): 669-672, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27816906

RESUMO

Pythium insidiosum is an aquatic oomycete that causes pythiosis, an important and severe disease of difficult treatment that affects humans, domestic and wild animals. This infection is often described in horses in Brazil and humans in Thailand. In clinical practice, we have observed many cases that do not respond to available therapies, indicating the need to explore alternative therapeutic approaches. In this sense, studies using metal compounds in conjunction with available antimicrobial agents have been demonstrated greater antimicrobial activity. Thus, in this research, we tested in vitro activities of metallic compounds containing cadmium, lead, copper, manganese, or zinc against 23 isolates of P. insidiosum. The assays were performed by broth microdilution based on CLSI M38-A2 document. The minimum inhibitory and fungicidal concentrations were established for all isolates. Copper acetate and cadmium acetate showed the highest inhibitory effects, with minimal inhibitory concentration ranging from 4-64 µg/ml and 16-256 µg/ml, respectively. The mean geometric for minimal fungicidal concentrations were, respectively, 26 µg/ml and 111.43 µg/ml for copper acetate and cadmium acetate. These results suggest that copper and cadmium can inhibit P. insidiosum growth, highlighting the greater inhibitory activity of copper acetate. In addition, our results propose that copper and/or cadmium compounds can be used in upcoming researches to formulate effective new complexed drugs against P. insidiosum in in vitro and in vivo experimental models.


Assuntos
Antifúngicos/farmacologia , Pythium/efeitos dos fármacos , Acetatos/farmacologia , Antifúngicos/química , Cádmio/farmacologia , Cobre/farmacologia , Técnicas In Vitro , Manganês/farmacologia , Testes de Sensibilidade Microbiana , Compostos Organometálicos/farmacologia , Pythium/isolamento & purificação , Sulfato de Zinco/farmacologia
17.
Parasitology ; 144(2): 214-219, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27762176

RESUMO

Cystic echinococcosis is a zoonotic disease of difficult diagnosis and treatment. The use of protoscolicidal agents in procedures is of utmost importance for treatment success. This study was aimed at analysing the in vitro and ex vivo activity of Melaleuca alternifolia oil (tea tree oil - TTO), its nanoemulsion formulation (NE-TTO) and its major component (terpinen-4-ol) against Echinococcus ortleppi protoscoleces obtained from cattle. Concentrations of 2·5, 5 and 10 mg mL-1 of TTO, 10 mg mL-1 of NE-TTO and 1, 1·5 and 2 mg mL-1 of terpinen-4-ol were evaluated in vitro against protoscoleces at 5, 10, 15 and 30 min. TTO was also injected directly into hydatid cysts (ex vivo analysis, n = 20) and the viability of protoscoleces was evaluated at 5, 15 and 30 min. The results indicated protoscolicidal effect at all tested formulations and concentrations. Terpinen-4-ol (2 mg mL-1) activity was superior when compared with the highest concentration of TTO. NE-TTO reached a gradual protoscolicidal effect. TTO at 20 mg mL-1 showed 90% protoscolicidal action in hydatid cysts at 5 min. The results showed that TTO affects the viability of E. ortleppi protoscoleces, suggesting a new protoscolicidal option to the treatment of cystic equinococcosis.


Assuntos
Anti-Helmínticos/farmacologia , Echinococcus/efeitos dos fármacos , Melaleuca , Óleo de Melaleuca/farmacologia , Animais
18.
Infect Genet Evol ; 48: 58-63, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27894990

RESUMO

Pythium insidiosum is an important oomycete due to its ability to infect humans and animals. It causes pythiosis, a disease of difficult treatment that occurs more frequently in humans in Thailand and in horses in Brazil. Since cell-wall components are frequently related to host shifts, we decided here to use sequences from the exo-1,3-ß-glucanase gene (exo1), which encodes an immunodominant protein putatively involved in cell wall remodeling, to investigate the microevolutionary relationships of Brazilian and Thai isolates of P. insidiosum. After neutrality ratification, the phylogenetic analyses performed through Maximum parsimony (MP), Neighbor-joining (NJ), Maximum likelihood (ML), and Bayesian analysis (BA) strongly supported Thai isolates being paraphyletic in relation to those from Brazil. The structure recovered by these analyses, as well as by Spatial Analysis of Molecular Variance (SAMOVA), suggests the subdivision of P. insidiosum into three clades or population groups, which are able to explain almost 81% of the variation encountered for exo1. Moreover, the two identified Thai clades were almost as strongly differentiated between each other, as they were from the Brazilian clade, suggesting an ancient Asian subdivision. The derived positioning in the phylogenetic tree, linked to the lower diversity values and the recent expansion signs detected for the Brazilian clade, further support this clade as derived in relation to the Asian populations. Thus, although some patterns presented here are compatible with those recovered with different molecular markers, exo1 was revealed to be a good marker for studying evolution in Pythium, providing robust and strongly supported results with regard to the patterns of origin and diversification of P. insidiosum.


Assuntos
Glucana 1,3-beta-Glucosidase/genética , Pythium/genética , Brasil , Evolução Molecular , Variação Genética , Filogenia , Pythium/enzimologia , Tailândia
19.
Acta Trop ; 164: 41-44, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27554941

RESUMO

Echinococcosis is a cosmopolitan zoonotic infection that affects humans and animals. The aim of this study was to identify and characterize the fertile hydatid cysts from bovine viscera in order to verify different species and/or genotypes present in Southern Brazil. Firstly, cysts were collected from a slaughterhouse, which received animals from different regions of Rio Grande do Sul State (RS), considered an important area of occurrence of cystic echinococcosis. In total, 2396 cysts were analyzed by microscopy to verify the presence of protoscoleces. Protoscoleces were detected in 291 samples and were classified as fertile hydatid cysts. Total DNA was extracted from protoscoleces and amplified by polymerase chain reaction (PCR). Two hundred and fifty-one samples were identified by PCR and characterized as G5/G6/G7 genotypes, of which 40 belonged to Echinococcus granulosus sensu stricto (G1-G3). PCR was also performed, using G5-specific primers to identify 250 samples as Echinococcus ortleppi (G5). Only one sample was identified as Echinococcus canadensis (G7) by DNA sequencing using primers specific for the coxI gene. Phylogenetic analysis was also performed and identified three distinct groups E1 (G5), E2 (G7), and E3 (G1-G3), which were grouped according to similarity of their sequences. The study highlights the fact that E. granulosus sensu stricto, E. ortleppi, and E. canadensis (G7) were infecting cattle in RS, emphasizing the adaptation of different species of Echinococcus to this intermediate host.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Equinococose/epidemiologia , Equinococose/parasitologia , Echinococcus/genética , Animais , Brasil/epidemiologia , Bovinos , Equinococose/veterinária , Echinococcus/isolamento & purificação , Genótipo
20.
Ciênc. rural ; 46(5): 839-846, May 2016. tab
Artigo em Inglês | LILACS | ID: lil-777273

RESUMO

ABSTRACT: Conidiobolomycosis is an emerging disease caused by fungi of the cosmopolitan genus Conidiobolus. Particular strains of Conidiobolus coronatus, Conidiobolus incongruus and Conidiobolus lamprauges, mainly from tropical or sub-tropical origin, cause the mycosis in humans and animals, domestic or wild. Lesions are usually granulomatous and necrotic in character, presenting two clinical forms: rhinofacial and nasopharyngeal. This review includes the main features of the disease in sheep, with an emphasis on the epidemiology, clinical aspects, and diagnosis of infections caused by Conidiobolus spp. in Brazil. In this country, the disease is endemic in the Northeast and Midwest, affecting predominantly woolless sheep breeds and occasioning death in the majority of the studied cases. The species responsible for infections of sheep are C. coronatus and C. lamprauges and the predominant clinical presentation is nasopharyngeal. These fungal infections are very important, since they compromise the health status of the sheep flock and cause serious economic losses to the sheep industry. Thus, research is needed to investigate faster tools for diagnosis and effective methods for the control and treatment of conidiobolomycosis.


RESUMO: Conidiobolomicose é uma enfermidade emergente causada por fungos cosmopolitas do gênero Conidiobolus. Isolados de Conidiobolus coronatus, Conidiobolus incongruus e Conidiobolus lamprauges, principalmente de origem tropical e subtropical, afetam humanos, animais domésticos e silvestres. As lesões da conidiobolomicose normalmente são de caráter granulomatoso e necrótico, apresentando-se sob duas formas clínicas: rinofacial e nasofaríngea. O presente artigo tem como objetivo revisar as principais características da doença em ovinos, particularizando a epidemiologia, assim como os aspectos clínicos e o diagnóstico das infecções causadas por Conidiobolus spp. no Brasil. Neste País, a enfermidade é endêmica nas regiões nordeste e centro-oeste, afetando ovinos predominantemente de raças deslanadas, ocasionando a morte na grande maioria dos casos estudados. As espécies do fungo responsáveis pelas infecções em ovinos são C. coronatus e C. lamprauges e a forma clínica predominante é a nasofaríngea. Tais infecções fúngicas são muito importantes, uma vez que comprometem o status sanitário do rebanho ovino e acarretam sérios prejuízos econômicos à ovinocultura. Dessa forma, pesquisas são necessárias para investigar ferramentas rápidas de diagnóstico e métodos eficazes de controle e tratamento da conidiobolomicose.

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