Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.022
Filtrar
1.
Clin Microbiol Infect ; 27(1): 83-88, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32745596

RESUMO

OBJECTIVES: To describe the burden, epidemiology and outcomes of co-infections and superinfections occurring in hospitalized patients with coronavirus disease 2019 (COVID-19). METHODS: We performed an observational cohort study of all consecutive patients admitted for ≥48 hours to the Hospital Clinic of Barcelona for COVID-19 (28 February to 22 April 2020) who were discharged or dead. We describe demographic, epidemiologic, laboratory and microbiologic results, as well as outcome data retrieved from electronic health records. RESULTS: Of a total of 989 consecutive patients with COVID-19, 72 (7.2%) had 88 other microbiologically confirmed infections: 74 were bacterial, seven fungal and seven viral. Community-acquired co-infection at COVID-19 diagnosis was uncommon (31/989, 3.1%) and mainly caused by Streptococcus pneumoniae and Staphylococcus aureus. A total of 51 hospital-acquired bacterial superinfections, mostly caused by Pseudomonas aeruginosa and Escherichia coli, were diagnosed in 43 patients (4.7%), with a mean (SD) time from hospital admission to superinfection diagnosis of 10.6 (6.6) days. Overall mortality was 9.8% (97/989). Patients with community-acquired co-infections and hospital-acquired superinfections had worse outcomes. CONCLUSIONS: Co-infection at COVID-19 diagnosis is uncommon. Few patients developed superinfections during hospitalization. These findings are different compared to those of other viral pandemics. As it relates to hospitalized patients with COVID-19, such findings could prove essential in defining the role of empiric antimicrobial therapy or stewardship strategies.


Assuntos
Infecções Bacterianas/epidemiologia , Infecção Hospitalar/epidemiologia , Micoses/epidemiologia , Superinfecção/epidemiologia , Viroses/epidemiologia , Idoso , Antibacterianos/uso terapêutico , Infecções Bacterianas/microbiologia , Infecções Bacterianas/mortalidade , Infecções Bacterianas/terapia , Técnicas de Tipagem Bacteriana , Hemocultura/métodos , /terapia , Coinfecção , Infecções Comunitárias Adquiridas , Infecção Hospitalar/microbiologia , Infecção Hospitalar/mortalidade , Infecção Hospitalar/terapia , Feminino , Hospitalização , Hospitais , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Micoses/microbiologia , Micoses/mortalidade , Micoses/terapia , Estudos Retrospectivos , Espanha/epidemiologia , Escarro/microbiologia , Superinfecção/mortalidade , Superinfecção/terapia , Superinfecção/virologia , Análise de Sobrevida , Viroses/mortalidade , Viroses/terapia , Viroses/virologia
2.
PLoS One ; 15(11): e0241119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33156870

RESUMO

Effectively planning conservation introductions involves assessing the suitability of both donor and recipient populations, including the landscape of disease risk. Chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), has caused extensive amphibian declines globally and may hamper reintroduction attempts. To determine Bd dynamics in potential source populations for conservation translocations of the threatened California red-legged frog (Rana draytonii) to Yosemite National Park, we conducted Bd sampling in two populations in the foothills of the Sierra Nevada Mountains, California, U.S.A. At one of two sites, we observed lethally high Bd loads in early post-metamorphic life stages and confirmed one chytridiomycosis-induced mortality, the first such report for this species. These results informed source population site selection for subsequent R. draytonii conservation translocations. Conservation efforts aimed at establishing new populations of R. draytonii in a landscape where Bd is ubiquitous can benefit from an improved understanding of risk through disease monitoring and ex situ infection studies.


Assuntos
Anuros/microbiologia , Micoses/microbiologia , Animais
3.
Medicine (Baltimore) ; 99(48): e23409, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33235120

RESUMO

BACKGROUND: Talaromyces marneffei (T marneffei), known as a significant pathogen in patients with AIDS in Southeast Asia, is a dimorphic fungus, which can cause deadly systematic infection in immunocompromised hosts. What is more, the dimorphic phase transition has been reported as a conspicuous process linked with virulence. Interestingly, the yeast form was found in infected individuals, representing the pathogenic phase. However, few researches were found to study the mechanism of dimorphic transition. Thus, a diverse insight into the dimorphic switch mechanism, is urgently needed and we are the first one to research the mechanism of dimorphism. METHODS: Firstly, we investigated the microarray of T. marneffei in the Gene Expression Omnibus database (GEO) for differentially expressed genes (DEGs). Then Database for Annotation, Visualization and Integrated Discovery (DAVID) v6.8 was employed to analyze the underlying enrichment and pathway in biological process of DEGs. Meanwhile, protein-protein interaction (PPI) network was constructed using STRING database. On the strength of the theory that similar amino acid sequences share similar structures, which play a decisive role on the function of protein, three dimensional structures of hub-genes were predicted to further investigate the likely function of hub-genes. RESULTS: GSE51109 was elected as the eligible series for the purpose of our research, including GSM1238923 (GSM23), GSM1238924 (GSM24), and GSM1238925 (GSM25). PMAA_012920, PMAA_028730, PMAA_068140, PMAA_092900, PMAA_032350 were the most remarkable genes in all of the three PPI networks, thus, were viewed as hub-genes. With regard to the three-dimensional construction, except that there was no significant prediction structure of PMAA_092900 with the criterion seq identify > 30%, GMQE: 0-1, QMEAN4: -4-0, the parallel templates for four structures were Crystal structure of Saccharomyces cerevesiae mitochondrial NADP(+)-dependent isocitrate dehydrogenase in complex with isocitrate, Organellar two-pore channels (TPCs), Yeast Isocitrate Dehydrogenase (Apo Form) and Crystal Structure Of ATP-Dependent Phosphoenolpyruvate Carboxykinase From Thermus thermophilus HB8 in order. CONCLUSION: The dimorphic transition of T. marneffei was viewed as a pathogenic factor and DEGs were observed. In-depth study of the function and pathway of DEGs revealed that PMAA_012920, PMAA_028730, PMAA_068140, PMAA_092900, PMAA_032350 were most likely acting as the hub-genes and were likely taking effect through regulating energy metabolism.


Assuntos
Regulação Fúngica da Expressão Gênica , Talaromyces/genética , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Biologia Computacional , Bases de Dados Genéticas , Redes Reguladoras de Genes , Humanos , Micoses/microbiologia , Conformação Proteica , Mapas de Interação de Proteínas , Talaromyces/patogenicidade
4.
PLoS One ; 15(11): e0242913, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33253322

RESUMO

Infectious diseases are considered major threats to biodiversity, however strategies to mitigate their impacts in the natural world are scarce and largely unsuccessful. Chytridiomycosis is responsible for the decline of hundreds of amphibian species worldwide, but an effective disease management strategy that could be applied across natural habitats is still lacking. In general amphibian larvae can be easily captured, offering opportunities to ascertain the impact of altering the abundance of hosts, considered to be a key parameter affecting the severity of the disease. Here, we report the results of two experiments to investigate how altering host abundance affects infection intensity in amphibian populations of a montane area of Central Spain suffering from lethal amphibian chytridiomycosis. Our laboratory-based experiment supported the conclusion that varying density had a significant effect on infection intensity when salamander larvae were housed at low densities. Our field experiment showed that reducing the abundance of salamander larvae in the field also had a significant, but weak, impact on infection the following year, but only when removals were extreme. While this suggests adjusting host abundance as a mitigation strategy to reduce infection intensity could be useful, our evidence suggests only heavy culling efforts will succeed, which may run contrary to objectives for conservation.


Assuntos
Anfíbios/genética , Micoses/microbiologia , Urodelos/genética , Anfíbios/crescimento & desenvolvimento , Anfíbios/microbiologia , Animais , Biodiversidade , Quitridiomicetos/genética , Ecossistema , Larva , Micoses/genética , Dinâmica Populacional , Espanha/epidemiologia , Urodelos/crescimento & desenvolvimento , Urodelos/microbiologia
5.
Nat Commun ; 11(1): 5393, 2020 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-33106491

RESUMO

Wildlife diseases are contributing to the current Earth's sixth mass extinction; one disease, chytridiomycosis, has caused mass amphibian die-offs. While global spread of a hypervirulent lineage of the fungus Batrachochytrium dendrobatidis (BdGPL) causes unprecedented loss of vertebrate diversity by decimating amphibian populations, its impact on amphibian communities is highly variable across regions. Here, we combine field data with in vitro and in vivo trials that demonstrate the presence of a markedly diverse variety of low virulence isolates of BdGPL in northern European amphibian communities. Pre-exposure to some of these low virulence isolates protects against disease following subsequent exposure to highly virulent BdGPL in midwife toads (Alytes obstetricans) and alters infection dynamics of its sister species B. salamandrivorans in newts (Triturus marmoratus), but not in salamanders (Salamandra salamandra). The key role of pathogen virulence in the complex host-pathogen-environment interaction supports efforts to limit pathogen pollution in a globalized world.


Assuntos
Anuros/microbiologia , Quitridiomicetos/patogenicidade , Micoses/veterinária , Salamandridae/microbiologia , Urodelos/microbiologia , Animais , Quitridiomicetos/classificação , Quitridiomicetos/fisiologia , Micoses/microbiologia , Virulência
6.
BMC Infect Dis ; 20(1): 800, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33115429

RESUMO

BACKGROUND: Talaromyces marneffei infection is an important opportunistic infection associated with acquired immune deficiency syndrome (AIDS). However, it is unusual in patients with non-AIDS and other non-immunosuppressed conditions. We report a case of delayed diagnosis of disseminated T. marneffei infection in non-AIDS, non-immunosuppressive and non-endemic conditions. CASE PRESENTATION: We describe a previously healthy 24-year-old man who complained of a 3-month history of intermittent diarrhea and a recent week of uncontrollable high fever. The HIV antibody test was negative. Enhanced abdominal computed tomography (CT) and integrated 18F-2-deoxy-2-fluoro-D-glucose position emission tomography/computed tomography (FDG PET/CT) both suspected malignant lymphoma. However, a large number of yeast-like cells were found in macrophages in cervical lymph node samples by hematoxylin and eosin stain and silver hexamine stain. Subsequent blood culture suggested T. marneffei infection. Metagenomic Next Generation Sequencing (mNGS) results suggested T. marneffei as the dominant pathogen. Unfortunately, the patient continued to develop acute liver failure and died due to adverse events associated with amphotericin B. CONCLUSIONS: Early diagnosis in HIV-negative patients who are otherwise not immunosuppressed and endemic poses a serious challenge. T. marneffei infection is an FDG-avid nonmalignant condition that may lead to false-positive FDG PET/CT scans. Nevertheless, integrated FDG PET/CT is necessary in patients with fever of unknown origin in the early period to perform earlier biopsy for histopathology and culture in highly avid sites and to avoid delays in diagnosis and treatment.


Assuntos
Linfoma/diagnóstico por imagem , Micoses/diagnóstico , Talaromyces/genética , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/virologia , Anfotericina B/efeitos adversos , Anfotericina B/uso terapêutico , Antifúngicos/efeitos adversos , Antifúngicos/uso terapêutico , China , Diagnóstico Tardio , Diagnóstico Diferencial , Evolução Fatal , Febre , HIV/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/mortalidade , Masculino , Micoses/tratamento farmacológico , Micoses/microbiologia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Talaromyces/isolamento & purificação , Tomografia Computadorizada por Raios X , Adulto Jovem
7.
PLoS One ; 15(10): e0241048, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33119670

RESUMO

To prevent transmission of the pathogenic chytrid fungi Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal), hygiene protocols prescribe the single use of disposable gloves for handling amphibians. We discovered that rinse water from nitrile gloves instantly kills 99% of Bd and Bsal zoospores. Transmission experiments using midwife toads (Alytes obstetricans) and Bd, and Alpine newts (Ichthyosaura alpestris) and Bsal, show that the use of the same pair of gloves for 2 subsequent individuals does not result in significant transmission of any chytrid fungus. In contrast, handling infected amphibians bare-handed caused transmission of Bsal in 4 out of 10 replicates, but did not result in transmission of Bd. Based on the manufacturer's information, high resolution mass spectrometry (HRMS) and colorimetric tests, calcium lactate and calcium nitrate were identified as compounds with antifungal activity against both Bd and Bsal. These findings corroborate the importance of wearing gloves as an important sanitary measure in amphibian disease prevention. If the highly recommended single use of gloves is not possible, handling multiple post-metamorphic amphibians with the same pair of nitrile gloves should still be preferred above bare-handed manipulation.


Assuntos
Anfíbios/microbiologia , Antifúngicos/farmacologia , Quitridiomicetos/efeitos dos fármacos , Luvas Protetoras/estatística & dados numéricos , Higiene/normas , Micoses/prevenção & controle , Animais , Compostos de Cálcio/farmacologia , Quitridiomicetos/crescimento & desenvolvimento , Quitridiomicetos/patogenicidade , Humanos , Lactatos/farmacologia , Micoses/microbiologia , Micoses/transmissão , Nitratos/farmacologia
8.
PLoS One ; 15(10): e0240545, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33057351

RESUMO

The bacterial strain, EMM-1, was isolated from the rhizosphere of red maize ("Rojo Criollo") and identified as Pseudomonas protegens EMM-1 based on phylogenetic analysis of 16S rDNA, rpoB, rpoD, and gyrB gene sequences. We uncovered genes involved in the production of antimicrobial compounds like 2,4-diacetylphloroglucinol (2,4-DAPG), pyoluteorin, and lectin-like bacteriocins. These antimicrobial compounds are also produced by other fluorescent pseudomonads alike P. protegens. Double-layer agar assay showed that P. protegens EMM-1 inhibited the growth of several multidrug-resistant (MDR) bacteria, especially clinical isolates of the genera Klebsiella and ß-hemolytic Streptococcus. This strain also displayed inhibitory effects against diverse fungi, such as Aspergillus, Botrytis, and Fusarium. Besides, a crude extract of inhibitory substances secreted into agar was obtained after the cold-leaching process, and physicochemical characterization was performed. The partially purified inhibitory substances produced by P. protegens EMM-1 inhibited the growth of Streptococcus sp. and Microbacterium sp., but no inhibitory effect was noted for other bacterial or fungal strains. The molecular weight determined after ultrafiltration was between 3 and 10 kDa. The inhibitory activity was thermally stable up to 60°C (but completely lost at 100°C), and the inhibitory activity remained active in a wide pH range (from 3 to 9). After treatment with a protease from Bacillus licheniformis, the inhibitory activity was decreased by 90%, suggesting the presence of proteic natural compounds. All these findings suggested that P. protegens EMM-1 is a potential source of antimicrobials to be used against pathogens for humans and plants.


Assuntos
Anti-Infecciosos/toxicidade , Bacteriocinas/toxicidade , Pseudomonas/metabolismo , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/metabolismo , Anti-Infecciosos/uso terapêutico , Antibiose , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Bacteriocinas/isolamento & purificação , Bacteriocinas/metabolismo , Bacteriocinas/uso terapêutico , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Micoses/tratamento farmacológico , Micoses/microbiologia , Doenças das Plantas/prevenção & controle , Rizosfera , Zea mays/microbiologia
9.
Eye Contact Lens ; 46(6): e66-e68, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33044373

RESUMO

We report a rare case of dematiaceous fungus colonization in the therapeutic bandage contact lens (BCL), in an eye with peripheral ulcerative keratitis. Bandage contact lens removal and appropriate treatment resulted in improvement of the visual acuity and prevented the spread of fungus to the underlying ocular structures. Microbiological evaluation of the BCL showed dematiaceous fungal filaments, and the fungus was identified as Bipolaris species. In patients with pigmented plaque-like lesions, with BCL in situ, dematiaceous fungus on the undersurface of the BCL should be kept in mind. Patient education regarding the importance of frequent BCL replacement, proper ocular hygiene, and timely follow-up should be emphasized.


Assuntos
Ascomicetos/isolamento & purificação , Betacoronavirus , Lentes de Contato/microbiologia , Úlcera da Córnea/microbiologia , Infecções por Coronavirus/epidemiologia , Infecções Oculares Fúngicas/microbiologia , Micoses/microbiologia , Pneumonia Viral/epidemiologia , Idoso , Antifúngicos/uso terapêutico , Bandagens , Carboximetilcelulose Sódica/uso terapêutico , Úlcera da Córnea/diagnóstico , Úlcera da Córnea/tratamento farmacológico , Infecções Oculares Fúngicas/diagnóstico , Infecções Oculares Fúngicas/tratamento farmacológico , Humanos , Perda de Seguimento , Masculino , Micoses/diagnóstico , Micoses/tratamento farmacológico , Natamicina/uso terapêutico , Pandemias , Tomografia de Coerência Óptica , Acuidade Visual
10.
Future Microbiol ; 15: 1405-1413, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33085538

RESUMO

As the global COVID-19 pandemic spreads worldwide, new challenges arise in the clinical landscape. The need for reliable diagnostic methods, treatments and vaccines for COVID-19 is the major worldwide urgency. While these goals are especially important, the growing risk of co-infections is a major threat not only to the health systems but also to patients' lives. Although there is still not enough published statistical data, co-infections in COVID-19 patients found that a significant number of patients hospitalized with COVID-19 developed secondary systemic mycoses that led to serious complications and even death. This review will discuss some of these important findings with the major aim to warn the population about the high risk of concomitant systemic mycoses in individuals weakened by COVID-19.


Assuntos
Infecções por Coronavirus/complicações , Micoses/complicações , Infecções Oportunistas/complicações , Pneumonia Viral/complicações , Betacoronavirus/patogenicidade , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/patologia , Glucocorticoides/efeitos adversos , Humanos , Infecções Fúngicas Invasivas/complicações , Infecções Fúngicas Invasivas/diagnóstico , Infecções Fúngicas Invasivas/epidemiologia , Infecções Fúngicas Invasivas/microbiologia , Pneumopatias Fúngicas/complicações , Pneumopatias Fúngicas/diagnóstico , Pneumopatias Fúngicas/epidemiologia , Pneumopatias Fúngicas/microbiologia , Micoses/diagnóstico , Micoses/epidemiologia , Micoses/microbiologia , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/epidemiologia , Infecções Oportunistas/microbiologia , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/patologia , Risco
11.
J Med Microbiol ; 69(11): 1285-1292, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32945764

RESUMO

Introduction. Papiliotrema laurentii, formerly Cryptococcus laurentii, is typically isolated from environmental sources, but also occasionally from clinical specimens. Other close relatives may be misidentified as P. laurentii by phenotypic methods. P. laurentii usually lacks melanin; however, melanin-forming strains have also been isolated.Hypothesis/Gap Statement. Although melanin production by encapsulated budding yeasts is considered a major virulence factor, the comparative pathogenicity of melanin-forming and non-melanized environmental strains of P. laurentii has rarely been studied.Aim. We performed phenotypic and molecular identification and determined the genotypic heterogeneity among P. laurentii isolates. We also studied the pathogenicity of melanin-forming and non-melanized strains in normal and immunosuppressed mice.Methodology. Eleven environmental isolates were tested for their identity by Vitek2 and/or ID32C systems, and by PCR-sequencing of the internal transcribed spacer (ITS) region and D1/D2 domains of ribosomal DNA (rDNA). Genotypic heterogeneity was studied by sequence comparisons. The pathogenicity of melanized and non-melanized P. laurentii strains was studied in intravenously infected normal and immunosuppressed BALB/c mice.Results. Phenotypic methods identified seven of the environmental isolates, while PCR-sequencing of the ITS region and D1/D2 domains of rDNA detected two and five isolates, respectively, as P. laurentii. Sequence comparisons demonstrated genotypic heterogeneity among P. laurentii. The remaining four environmental isolates yielded expected results. None of the normal mice infected with 105 cells of melanized/non-melanized P. laurentii strains died. Infection of immunosuppressed mice with 107 cells caused higher mortality with non-melanized P. laurentii, while viable counts in brain/lung tissue were higher in mice infected with a melanized strain and were detectable for up to 14 days.Conclusion. Phenotypic methods lacked specificity, but PCR-sequencing of D1/D2 domains correctly identified P. laurentii and sequence comparisons demonstrated the genotypic heterogeneity of the isolates. Both melanized and non-melanized strains at a higher dose caused mortality in immunosuppressed mice and persisted in brain/lung tissue up to 14 days post-infection.


Assuntos
Basidiomycota/genética , Basidiomycota/patogenicidade , Microbiologia Ambiental , Variação Genética , Micoses/microbiologia , Animais , Basidiomycota/classificação , DNA Fúngico/genética , DNA Intergênico/genética , Feminino , Genótipo , Hospedeiro Imunocomprometido , Melaninas , Camundongos , Camundongos Endogâmicos BALB C , Técnicas de Tipagem Micológica , Filogenia , Análise de Sequência de DNA , Virulência , Fatores de Virulência/genética
12.
PLoS Pathog ; 16(9): e1008800, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32913361

RESUMO

Soil-dwelling animals are at risk of pathogen infection in soils. When choosing nesting sites, animals could reduce this risk by avoiding contact with pathogens, yet there is currently little evidence. We tested this hypothesis using Solenopsis invicta as a model system. Newly mated queens of S. invicta were found to nest preferentially in soil containing more actinobacteria of Streptomyces and Nocardiopsis and to be attracted to two volatiles produced by these bacteria, geosmin and 2-methylisoborneol. Actinobacteria-rich soil was favored by S. invicta and this soil contained fewer putative entomopathogenic fungi than adjacent areas. Queens in such soil benefited from a higher survival rate. In culture, isolated actinobacteria inhibited entomopathogenic fungi, suggested that their presence may reduce the risk of fungal infection. These results indicated a soil-dwelling ant may choose nest sites presenting relatively low pathogen risk by detecting the odors produced by bacteria with anti-fungal properties.


Assuntos
Actinobacteria/fisiologia , Anti-Infecciosos/farmacologia , Formigas/fisiologia , Fungos/efeitos dos fármacos , Micoses/prevenção & controle , Comportamento de Nidação/efeitos dos fármacos , Compostos Orgânicos Voláteis/farmacologia , Animais , Formigas/microbiologia , Micoses/microbiologia , Microbiologia do Solo , Simbiose
13.
PLoS One ; 15(9): e0235370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915779

RESUMO

Controlled experiments are one approach to understanding the pathogenicity of etiologic agents to susceptible hosts. The recently discovered fungal pathogen, Batrachochytrium salamandrivorans (Bsal), has resulted in a surge of experimental investigations because of its potential to impact global salamander biodiversity. However, variation in experimental methodologies could thwart knowledge advancement by introducing confounding factors that make comparisons difficult among studies. Thus, our objective was to evaluate if variation in experimental methods changed inferences made on the pathogenicity of Bsal. We tested whether passage duration of Bsal culture, exposure method of the host to Bsal (water bath vs. skin inoculation), Bsal culturing method (liquid vs. plated), host husbandry conditions (aquatic vs. terrestrial), and skin swabbing frequency influenced diseased-induced mortality in a susceptible host species, the eastern newt (Notophthalmus viridescens). We found that disease-induced mortality was faster for eastern newts when exposed to a low passage isolate, when newts were housed in terrestrial environments, and if exposure to zoospores occurred via water bath. We did not detect differences in disease-induced mortality between culturing methods or swabbing frequencies. Our results illustrate the need to standardize methods among Bsal experiments. We provide suggestions for future Bsal experiments in the context of hypothesis testing and discuss the ecological implications of our results.


Assuntos
Quitridiomicetos/patogenicidade , Micoses/veterinária , Urodelos/microbiologia , Animais , Técnicas de Cultura de Células , Quitridiomicetos/isolamento & purificação , Quitridiomicetos/fisiologia , Micoses/microbiologia , Micoses/patologia , Pele/microbiologia , Pele/patologia , Coloração e Rotulagem , Urodelos/fisiologia
15.
Sci Rep ; 10(1): 15145, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934254

RESUMO

Two species of parasitic fungi from the phylum Chytridiomycota (chytrids) are annihilating global amphibian populations. These chytrid species-Batrachochytrium dendrobatidis and B. salamandrivorans-have high rates of mortality and transmission. Upon establishing infection in amphibians, chytrids rapidly multiply within the skin and disrupt their hosts' vital homeostasis mechanisms. Current disease models suggest that chytrid fungi locate and infect their hosts during a motile, unicellular 'zoospore' life stage. Moreover, other chytrid species parasitize organisms from across the tree of life, making future epidemics in new hosts a likely possibility. Efforts to mitigate the damage and spread of chytrid disease have been stymied by the lack of knowledge about basic chytrid biology and tools with which to test molecular hypotheses about disease mechanisms. To overcome this bottleneck, we have developed high-efficiency delivery of molecular payloads into chytrid zoospores using electroporation. Our electroporation protocols result in payload delivery to between 75 and 97% of living cells of three species: B. dendrobatidis, B. salamandrivorans, and a non-pathogenic relative, Spizellomyces punctatus. This method lays the foundation for molecular genetic tools needed to establish ecological mitigation strategies and answer broader questions in evolutionary and cell biology.


Assuntos
Anfíbios/crescimento & desenvolvimento , Doenças dos Animais/epidemiologia , Quitridiomicetos/patogenicidade , Eletroporação/métodos , Micoses/veterinária , Esporos Fúngicos/isolamento & purificação , Anfíbios/microbiologia , Animais , Interações Hospedeiro-Patógeno , Micoses/microbiologia , Esporos Fúngicos/fisiologia
16.
Mol Ecol ; 29(17): 3167-3169, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32745298

RESUMO

What happens when two emergent diseases infect the same host? In a From the Cover article in this issue of Molecular Ecology, McDonald et al. (2020) compare transcriptomic responses to co-infection by the two chytrid fungi in the skin, liver and spleen of Eastern newts (Notophthalmus viridescens). Novel molecular tools, such as high-throughput DNA sequencing for genome discovery and transcriptomics, have revolutionized our understanding of host-pathogen interactions and disease ecology (Güimil et al. 2005; Rosenblum et al. 2012). For example, epidemiologists are using genomic data to track the spread of the emergent SARS-CoV-2 in real time, both locally and globally. RNA sequencing (RNA-Seq) is routinely employed to study response to disease in humans, improving disease diagnostics, profiling and development of intervention strategies. Transcriptomic profiles may be particularly informative for emergent diseases, whose pathologies and effect on host phenotype are poorly known. Fungal pathogens increasingly threaten a variety of wild and domesticated organisms (Fisher et al. 2012), and two chytrid fungi attacking amphibians are causing one of the worst losses of vertebrate biodiversity ever recorded (Scheele et al. 2019).


Assuntos
Quitridiomicetos/imunologia , Micoses/veterinária , Salamandridae/imunologia , Animais , Coinfecção/imunologia , Perfilação da Expressão Gênica , Humanos , Fígado/microbiologia , Micoses/imunologia , Micoses/microbiologia , Salamandridae/genética , Salamandridae/microbiologia , Pele/microbiologia , Baço/microbiologia , Transcriptoma/genética
17.
Appl Microbiol Biotechnol ; 104(18): 7777-7785, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32780290

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel ß-coronavirus, is the main pathogenic agent of the rapidly spreading pneumonia called coronavirus disease 2019 (COVID-19). SARS-CoV-2 infects much more people, especially the elder population, around the world than other coronavirus, such as SARS-CoV and MERS-CoV, which is challenging current global public health system. Beyond the pathogenesis of SARS-CoV-2, microbial coinfection plays an important role in the occurrence and development of SARS-CoV-2 infection by raising the difficulties of diagnosis, treatment, prognosis of COVID-19, and even increasing the disease symptom and mortality. We summarize the coinfection of virus, bacteria and fungi with SARS-CoV-2, their effects on COVID-19, the reasons of coinfection, and the diagnosis to emphasize the importance of microbial coinfection in COVID-19. KEY POINTS: • Microbial coinfection is a nonnegligible factor in COVID-19. • Microbial coinfection exacerbates the processes of the occurrence, development and prognosis of COVID-19, and the difficulties of clinical diagnosis and treatment. • Different virus, bacteria, and fungi contributed to the coinfection with SARS-CoV-2.


Assuntos
Infecções Bacterianas/epidemiologia , Infecções por Coronavirus/epidemiologia , Síndrome da Liberação de Citocina/epidemiologia , Linfopenia/epidemiologia , Micoses/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Viroses/epidemiologia , Antibacterianos/uso terapêutico , Antivirais/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Infecções Bacterianas/virologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Coinfecção , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/microbiologia , Infecções por Coronavirus/virologia , Síndrome da Liberação de Citocina/tratamento farmacológico , Síndrome da Liberação de Citocina/microbiologia , Síndrome da Liberação de Citocina/virologia , Citocinas/biossíntese , Progressão da Doença , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Linfócitos/microbiologia , Linfócitos/virologia , Linfopenia/tratamento farmacológico , Linfopenia/microbiologia , Linfopenia/virologia , Micoses/tratamento farmacológico , Micoses/microbiologia , Micoses/virologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/microbiologia , Pneumonia Viral/virologia , Viroses/tratamento farmacológico , Viroses/microbiologia , Viroses/virologia
18.
Emerg Microbes Infect ; 9(1): 1958-1964, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32815458

RESUMO

Objectives Severe or critical COVID-19 is associated with intensive care unit admission, increased secondary infection rate, and would lead to significant worsened prognosis. Risks and characteristics relating to secondary infections in severe COVID-19 have not been described. Methods Severe and critical COVID-19 patients from Shanghai were included. We collected lower respiratory, urine, catheters, and blood samples according to clinical necessity and culture and mNGS were performed. Clinical and laboratory data were archived. Results We found 57.89% (22/38) patients developed secondary infections. The patient receiving invasive mechanical ventilation or in critical state has a higher chance of secondary infections (P<0.0001). The most common infections were respiratory, blood-stream and urinary infections, and in respiratory infections, the most detected pathogens were gram-negative bacteria (26, 50.00%), following by gram-positive bacteria (14, 26.92%), virus (6, 11.54%), fungi (4, 7.69%), and others (2, 3.85%). Respiratory Infection rate post high flow, tracheal intubation, and tracheotomy were 12.90% (4/31), 30.43% (7/23), and 92.31% (12/13) respectively. Secondary infections would lead to lower discharge rate and higher mortality rate. Conclusion Our study originally illustrated secondary infection proportion in severe and critical COVID-19 patients. Culture accompanied with metagenomics sequencing increased pathogen diagnostic rate. Secondary infections risks increased after receiving invasive respiratory ventilations and intravascular devices, and would lead to a lower discharge rate and a higher mortality rate.


Assuntos
Bacteriemia/patologia , Infecções Bacterianas/patologia , Infecções por Coronavirus/patologia , Fungemia/patologia , Micoses/patologia , Infecções Oportunistas/patologia , Pneumonia Viral/patologia , Infecções Respiratórias/patologia , Infecções Urinárias/patologia , Idoso , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Bacteriemia/virologia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/mortalidade , Infecções Bacterianas/virologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/microbiologia , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/virologia , Estado Terminal , Feminino , Fungemia/microbiologia , Fungemia/mortalidade , Fungemia/virologia , Fungos/patogenicidade , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Positivas/patogenicidade , Humanos , Unidades de Terapia Intensiva , Pulmão/microbiologia , Pulmão/patologia , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Micoses/microbiologia , Micoses/mortalidade , Micoses/virologia , Infecções Oportunistas/microbiologia , Infecções Oportunistas/mortalidade , Infecções Oportunistas/virologia , Pandemias , Pneumonia Viral/microbiologia , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Respiração Artificial/efeitos adversos , Infecções Respiratórias/microbiologia , Infecções Respiratórias/mortalidade , Infecções Respiratórias/virologia , Estudos Retrospectivos , Risco , Índice de Gravidade de Doença , Análise de Sobrevida , Infecções Urinárias/microbiologia , Infecções Urinárias/mortalidade , Infecções Urinárias/virologia
19.
PLoS One ; 15(8): e0238252, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857797

RESUMO

We report on aerobic "environmental" bacteria isolated from European honey bees (Apis mellifera). We determined the number of culturable aerobic bacteria in the gut of nurse bees sampled from locations around Australia. Bees from healthy colonies had 107-108 aerobic bacteria per g of bee gut, while bees from colonies with chalkbrood consistently had significantly fewer bacteria (104-105 bacteria per g). When colonies recovered from chalkbrood, bacterial numbers returned to normal levels, suggesting that counting aerobic bacteria in the gut could be used to predict an outbreak of the disease. Furthermore, Western Australian bees from the "Better Bees" program (bred to promote hygienic behaviour) had significantly higher numbers of aerobic gut bacteria compared to regular bees from healthy colonies. Bacteria with the ability to inhibit the chalkbrood pathogen were found in most bees from regular colonies (> 60%) but only in a few "Better Bees" (10%). Phylogenetic analysis of aerobic bacterial isolates that inhibited the chalkbrood pathogen revealed a close relationship (>97% sequence identity) to the genera Bacillus, Klebsiella, Pantoea, Hafnia, and Enterobacter (bacteria that have previously been isolated from honey bees), but we also isolated Maccrococcus and Frigoribacterium species (bacteria that were not previously identified in bees). Finally, we investigated the ability of bacteria to inhibit the chalkbrood fungus Ascosphaera apis. Mass spectroscopy analysis revealed that the bee gut isolates Frigoribacterium sp. and Bacillus senegalensis produce gluconic acid. We further found that this simple sugar is involved in chalkbrood fungal hyphal lysis and cytoplasmic leakage. Our findings suggest that "environmental" gut bacteria may help bees to control the chalkbrood pathogen.


Assuntos
Abelhas/microbiologia , Microbioma Gastrointestinal , Micoses/veterinária , Animais , Austrália , Bactérias/genética , Bactérias/metabolismo , Criação de Abelhas , Micoses/microbiologia , Filogenia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA