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1.
Med Mycol ; 62(3)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38383897

RESUMO

In Ghana, most laboratory diagnoses of severe mycoses are based on histopathology findings due to inadequate availability of serology, culture, and molecular tests. The aim of this study was to evaluate the spectrum of mycoses diagnosed in Ghana. We retrospectively reviewed reports from 2012 to 2021 from three major pathology laboratories in Ghana to identify reports indicating the presence of fungal elements and diagnosis of a mycosis, then extracted demographic, clinical history, site of infection, stain(s), used and diagnosed mycosis details. Over the 10-year period, 107 cases were found. No apparent increasing and decreasing trend in the number of cases per year or in a period was observed. The age range of affected patients was from 4 to 86 years. Special stains for fungi were only used in 22 of 107 (20.6%) of cases. The most frequently affected site was the sino-nasal area (34%). Mycosis type was determined for 58 (54.2%) cases, comprising aspergillosis (21), candidiasis (14), dermatophytosis (6), mucormycosis (3), two cases each of chromoblastomycosis, histoplasmosis, eumycetoma, entomophthoromycosis, sporotrichosis, and Malassezia infection and a single case each of cryptococcosis and deep onychomycosis. Of the 53 (49.5%) cases with presumptive diagnosis data, only seven (13.2%) had a pre-biopsy suspicion of mycosis. There is a wide spectrum of mycoses in Ghana, including endemic mycoses not previously reported. Improving the use of special fungal stains could increase yield and mycoses identification. Laboratory diagnostic capacity needs enhancement to complement histopathology investigations with serology, culture, and molecular methods.


In Ghana, diagnosis of mycoses is mainly based on histopathology findings. To appreciate the varied mycoses diagnosed, we reviewed the reports of major laboratories from 2012 to 2021 and found 107 cases including endemic, rare, and previously unreported cases with fungal stains unusually used.


Assuntos
Aspergilose , Histoplasmose , Micoses , Humanos , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Gana/epidemiologia , Micoses/patologia , Micoses/veterinária , Aspergilose/veterinária , Histoplasmose/veterinária
2.
BMC Oral Health ; 23(1): 441, 2023 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-37394471

RESUMO

BACKGROUND: Deep-seated fungal infections of the oral cavity present a diagnostic challenge as the clinical presentation is usually aggressive leading to misdiagnosis of malignancy. Nevertheless, the species of fungi responsible for such diseases in immunocompromised individuals are varied thus, further complicating the diagnosis. CASE PRESENTATION: Presented below is a case regarding the diagnosis and management of deep mycotic infection of the oral cavity caused by a fungus that very rarely causes disease in humans, the Verticillium species. CONCLUSIONS: The case highlights the fact that rare pathogens should also be considered in the differential diagnosis, especially in patients with debilitating conditions like uncontrolled diabetes. Likewise, histopathological evaluation and microbiological investigations are of paramount importance and remain the gold standard to reach a definitive diagnosis.


Assuntos
Micoses , Verticillium , Humanos , Micoses/diagnóstico , Micoses/microbiologia , Micoses/patologia , Diagnóstico Diferencial
3.
Environ Monit Assess ; 195(6): 662, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37169998

RESUMO

Snake fungal disease, caused by Ophidiomyces ophidiicola, is recognized as a potential concern for North American snakes. We tested skin swabs from Northern Pine Snakes (Pituophis melanoleucus melanoleucus) in the New Jersey pinelands for the presence of O. ophidiicola before emergence from hibernation. We used qPCR to test the collected swabs for the presence of O. ophidiicola, then determined pathogen prevalence as a function of sampling year, sampling location (skin lesion, healthy ventral skin, healthy head skin) sex, and age. There were no temporal trends in O. ophidiicola detection percentages on snakes, which varied from 58 to 83% in different years. Ophidiomyces ophidiicola detection on snakes was highest in swabs of skin lesions (71%) and lowest in head swabs (29%). Males had higher prevalence than females (82% versus 62%). The fungus was not detected in hatchling snakes (age 0) in the fall, but 75% of juveniles tested positive at the end of hibernation (age 1 year). We also screened hibernacula soil samples for the presence of O. ophidiicola. Where snakes hibernated, 69% of soil samples were positive for O. ophidiicola, and 85% of snakes lying on positive soil samples also tested positive for the pathogen. Although a high proportion of snakes (73%) tested positive for O. ophidiicola during our 4-year study, the snakes appeared healthy except for small skin lesions. We conclude that O. ophidiicola prevalence is high on hibernating Northern Pine Snakes and in the hibernacula soil, with a strong association between snakes and positive adjacent soil. This is the first demonstration that snakes likely become infected during hibernation.


Assuntos
Monitoramento Ambiental , Micoses , Masculino , Animais , Feminino , New Jersey/epidemiologia , Prevalência , Serpentes/microbiologia , Micoses/microbiologia , Micoses/patologia
4.
Int J Infect Dis ; 132: 93-98, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37072056

RESUMO

OBJECTIVES: Talaromyces marneffei is an emerging pathogen, and the number of infections in HIV-negative individuals is rapidly increasing. Nevertheless, there is no sufficient comprehensive report on this issue, and awareness needs to be raised among clinicians. METHODS: We analyzed the differences in the clinical data of patients who are HIV-negative and HIV-positive with Talaromyces marneffei infection (TMI) from 2018 to 2022. RESULTS: A total of 848 patients were included, among whom 104 were HIV-negative. The obvious differences between the HIV-positive and HIV-negative groups were as follows: (i) the patients who are HIV-negative were older and more likely to exhibit cough and rash, (ii) the time in days from symptom onset to diagnosis among patients who are HIV-negative was longer, (iii) the laboratory findings and radiological presentations seemed more severe in patients who are HIV-negative, (iv) differences were observed regarding the underlying conditions and co-infection pathogens, and correlation analysis showed that correlations existed for many indicators, (v) and persistent infection was more likely to occur in patients who are HIV-negative. CONCLUSION: TMI in patients who are HIV-negative differs from that in patients who are HIV-positive in many aspects, and more investigations are needed. Clinicians should be more aware of TMI in patients who are HIV-negative.


Assuntos
Infecções por HIV , Micoses , Talaromyces , Humanos , Micoses/complicações , Micoses/diagnóstico , Micoses/microbiologia , Micoses/patologia , Estudos Retrospectivos , Infecções por HIV/complicações , Masculino , Feminino , Adulto , Pessoa de Meia-Idade
5.
Nagoya J Med Sci ; 85(1): 123-126, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36923611

RESUMO

Blockade of the secretion of immunoglobulins leads to their accumulation in plasma cells, resulting in condensed immunoglobulins in the rough endoplasmic reticulum of plasma cells, termed Russell bodies. They are sometimes found in lymphoplasmacellular inflammation of the intestinal mucosa and in lymphoid cell malignancies, but only very rarely in skin diseases. Here, we report an 86-year-old female who presented with a lesion with the prominent accumulation of Russell bodies underlying pseudocarcinomatous hyperplasia with fungal infection in the face. Immunohistochemical staining showed the cells containing Russell bodies to be positive for CD138 and the Russell bodies to be positive for immunoglobulin κ and λ light chains. The present case suggests that when inflammatory cell infiltration with abundant round intracellular eosinophilic materials is observed in the dermis, the dermal accumulation of Russell bodies should be considered in cases with reactive pseudocarcinomatous hyperplasia with fungal infection.


Assuntos
Micoses , Dermatopatias , Feminino , Humanos , Idoso de 80 Anos ou mais , Hiperplasia/patologia , Imunoglobulinas , Plasmócitos/patologia , Dermatopatias/patologia , Micoses/patologia
6.
Med Ultrason ; 25(4): 423-434, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36996385

RESUMO

In this series of papers on comments and illustrations of the World Federation for Medicine and Biology (WFUMB) guidelines on contrast enhanced ultrasound (CEUS) the topics of parasitic and fungus infections are discussed. Improved detection and characterization of common focal liver lesions (FLL) are the main topics of these guidelines but detailed and illustrating information is missing. The focus in this paper on infectious (parasitic and fungus) focal liver lesions is on their appearance on B-mode and Doppler ultrasound and CEUS features. Knowledge of these data should help to raise awareness of these rarer findings, to think of these clinical pictures in the corresponding clinical situation, to interpret the ultrasound images correctly and thus to initiate the appropriate diagnostic and therapeutic steps in time.


Assuntos
Neoplasias Hepáticas , Micoses , Humanos , Neoplasias Hepáticas/patologia , Meios de Contraste , Fígado/diagnóstico por imagem , Fígado/patologia , Ultrassonografia/métodos , Micoses/diagnóstico por imagem , Micoses/patologia , Fungos
7.
Pediatr Dermatol ; 40(5): 900-903, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36813738

RESUMO

Congenital erosive and vesicular dermatosis (CEVD) is a rare skin condition that most commonly presents as erosive and vesicular lesions on the trunk and extremities in premature infants and heals with characteristic reticulated and supple scarring (RSS). The exact pathogenesis of CEVD is unknown and is typically a diagnosis of exclusion. We present the cases of two extremely premature neonates with Candida septicemia who were found to have diffuse, erythematous skin eruptions shortly after birth that ultimately healed with RSS. Through these cases, we highlight the importance of including fungal infection in the work-up of CEVD healing with RSS.


Assuntos
Micoses , Anormalidades da Pele , Dermatopatias Vesiculobolhosas , Lactente , Recém-Nascido , Humanos , Cicatriz/etiologia , Cicatrização , Dermatopatias Vesiculobolhosas/patologia , Pele/patologia , Anormalidades da Pele/patologia , Micoses/complicações , Micoses/patologia , Doenças Raras/complicações , Doenças Raras/patologia
8.
Clin Nucl Med ; 48(4): e167-e169, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36728208

RESUMO

ABSTRACT: Penicilliosis marneffei is an extremely rare fungal infectious disease and is especially rare in people with normal immunity. Penicilliosis marneffei restricted to the lung and involving the formation of a pulmonary tumor is difficult to distinguish from peripheral lung cancer. This kind of case has rarely been reported. We report the case of a 53-year-old man with penicilliosis marneffei misdiagnosed as lung cancer by 18 F-FDG PET/CT.


Assuntos
Neoplasias Pulmonares , Micoses , Penicillium , Masculino , Humanos , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Micoses/diagnóstico , Micoses/microbiologia , Micoses/patologia , Erros de Diagnóstico
9.
Can J Ophthalmol ; 58(5): 449-454, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35525264

RESUMO

OBJECTIVE: To evaluate the accuracy of the initial diagnosis in the case of fungal infections of the orbit and identify factors that may influence patient outcomes. METHODS: An institutional review board-approved retrospective chart review was conducted across 2 large academic centres to identify cases of fungal infections involving the orbit from January 1, 1998, to November 15, 2019. Data collected included patient demographics, past medical history, examination findings, diagnosis, treatment, imaging, and outcomes. RESULTS: Fifty cases of fungal infection involving the orbit were identified. Of these, 33 (66.0%) were initially misdiagnosed as nonfungal diagnoses. Sixteen patients (32.0%) received multiple initial diagnoses. The most common diagnoses on presentation were bacterial cellulitis (n = 12 of 50; 24.0%) and bacterial sinusitis (n = 12 of 50; 24.0%). These were followed by vascular and orbital inflammatory conditions (n = 9 of 50; 18.0%): 5 patients (10.0%) were clinically diagnosed with giant cell arteritis, 3 (6.0%) with nonspecific orbital inflammation, and 1 (2.0%) with optic neuritis. In this subset of patients, 77.8% (n = 7 of 9) were treated initially with systemic steroids. Additional initial diagnoses included neoplastic mass lesions, mucocele, dacryocystitis, cavernous sinus thrombosis, hemorrhage, tick-borne illness, allergic rhinitis, and allergic conjunctivitis. Misdiagnosis was significantly correlated with involvement of the masticator space on imaging (p = 0.04). CONCLUSION: Fungal infections of the orbit are misdiagnosed in 2 of 3 cases. Nearly 15% of patients who are later diagnosed with fungal disease of the orbit were initially treated with systemic steroids. Misdiagnosis is more frequent when the masticator space is involved.


Assuntos
Micoses , Doenças Orbitárias , Humanos , Órbita/patologia , Estudos Retrospectivos , Micoses/diagnóstico , Micoses/patologia , Doenças Orbitárias/microbiologia , Erros de Diagnóstico
11.
PLoS Negl Trop Dis ; 16(1): e0010144, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35073309

RESUMO

BACKGROUND: The awareness of non-malarial febrile illnesses (NMFIs) has been on the rise over the last decades. Therefore, we undertook a systematic literature review and meta-analysis of causative agents of non-malarial fevers on the African continent. METHODOLOGY: We searched for literature in African Journals Online, EMBASE, PubMed, Scopus, and Web of Science databases to identify aetiologic agents that had been reported and to determine summary estimates of the proportional morbidity rates (PMr) associated with these pathogens among fever patients. FINDINGS: A total of 133 studies comprising 391,835 patients from 25 of the 54 African countries were eligible. A wide array of aetiologic agents were described with considerable regional differences among the leading agents. Overall, bacterial pathogens tested from blood samples accounted for the largest proportion. The summary estimates from the meta-analysis were low for most of the agents. This may have resulted from a true low prevalence of the agents, the failure to test for many agents or the low sensitivity of the diagnostic methods applied. Our meta-regression analysis of study and population variables showed that diagnostic methods determined the PMr estimates of typhoidal Salmonella and Dengue virus. An increase in the PMr of Klebsiella spp. infections was observed over time. Furthermore, the status of patients as either inpatient or outpatient predicted the PMr of Haemophilus spp. infections. CONCLUSION: The small number of epidemiological studies and the variety of NMFI agents on the African continent emphasizes the need for harmonized studies with larger sample sizes. In particular, diagnostic procedures for NMFIs should be standardized to facilitate comparability of study results and to improve future meta-analyses. Reliable NMFI burden estimates will inform regional public health strategies.


Assuntos
Febre/epidemiologia , Febre/etiologia , África/epidemiologia , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/patologia , Humanos , Micoses/epidemiologia , Micoses/patologia , Doenças Parasitárias/epidemiologia , Doenças Parasitárias/patologia , Saúde Pública , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/patologia , Viroses/epidemiologia , Viroses/patologia
12.
J Clin Lab Anal ; 36(2): e24209, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34997792

RESUMO

BACKGROUND: Fungal rhinosinusitis (FRS) encompasses a various spectrum of diseases. Histopathology is the "reference method" for diagnosing FRS, but it cannot determine the genus and species. Moreover, in more than 50% of the histopathologically proven cases, the culture elicited no reliable results. This study was an attempt to evaluate the diagnostic efficiency of semi-nested polymerase chain reaction (PCR) from formalin-fixed paraffin-embedded (FFPE) functional endoscopic sinus surgery (FESS) in FRS patients. METHODS: One hundred ten specimens were subjected to DNA extraction and histopathology examination. The amplification of the ß-globin gene by conventional PCR was used to confirm the quality of extracted DNA. The semi-nested PCR was performed using ITS1, ITS2, and ITS4 primers during two steps. Sequencing the internal transcribed spacer region (ITS1-5.8S-ITS2) to identify causative agents was performed on PCR products. RESULTS: Sixty-four out of 110 samples were positive by histopathology evidence, of which 56 samples (87.5%) were positive by PCR. Out of 46 negative samples by histopathological methods, five samples (10.9%) yielded positive results by PCR. Sensitivity, specificity, positive predictive value, and negative predictive value of the semi-nested PCR method were reported 87.5%, 89.2%, 92.7%, and 85.2%, respectively. The kappa factor between PCR and histopathological methods was 0.76, indicating substantial agreements between these two tests. CONCLUSION: Due to the acceptable sensitivity and specificity of the present method, it might be used to diagnose fungal sinusitis infections along with microscopic techniques. This method is recommended to confirm the diagnose of suspected fungal sinusitis with negative histopathology results.


Assuntos
Fungos/genética , Micoses/diagnóstico , Inclusão em Parafina , Reação em Cadeia da Polimerase , Rinite/patologia , Sinusite/patologia , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Formaldeído , Fungos/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Micoses/patologia , Rinite/diagnóstico , Rinite/microbiologia , Sensibilidade e Especificidade , Sinusite/diagnóstico , Sinusite/microbiologia
13.
Diagn Cytopathol ; 50(3): 93-98, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34967146

RESUMO

BACKGROUND: COVID 19 has been rapidly spreading across the globe. As a result of alteration of the immune milieu by COVID 19 and its treatment, there has been a rise in opportunistic fungal infections particularly Mucormycosis in these patients. Delay in diagnosis of these fungal infections can be fatal. The usual diagnostic modalities used to detect Mucor include potassium hydroxide (KOH) mount, fungal culture, and histopathology. Since histopathology and fungal culture have a long turnaround time we are dependent on KOH mount for rapid results. Here we investigate the role of stained cytology smears in the rapid diagnosis of Mucormycosis. METHODS: A prospective observational study was conducted in a tertiary health care hospital on samples of patients clinically suspected to have Mucormycosis. We performed May Grunwald Giemsa (MGG) and Papanicolaou (PAP) stains on the remnant samples of nasal swabs/scrapings/biopsies after KOH test and fungal culture. We took 16 KOH positive and 16 KOH negative samples. We also examined 16 fresh samples from patients whose earlier samples were reported to be negative on KOH test. RESULTS: The 6/16 KOH positive samples were found to be positive on stained cytology smears and 2 were mixed infections wherein both Mucor and Aspergillus were seen. The 4/16 KOH negative samples were positive for Mucor with one sample having both Mucor and Aspergillus. The 3/16 repeat samples which were earlier negative on KOH test were positive for Mucor. CONCLUSION: Stained cytology smears if used in conjunction with KOH test can increase the overall sensitivity of detection of Mucormycosis and mixed infections.


Assuntos
COVID-19/patologia , COVID-19/virologia , Mucormicose/patologia , Mucormicose/virologia , SARS-CoV-2/patogenicidade , Biópsia/métodos , COVID-19/diagnóstico , Feminino , Humanos , Mucormicose/diagnóstico , Micoses/diagnóstico , Micoses/patologia , Estudos Prospectivos , Manejo de Espécimes/métodos , Esfregaço Vaginal/métodos
14.
Braz. J. Pharm. Sci. (Online) ; 58: e191024, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1394036

RESUMO

Abstract Posaconazole exerts an extended spectrum of antifungal activity against various strains of clinically relevant moulds and yeasts. In recent years, antifungal triazole posaconazole has become increasingly important for the prophylaxis and treatment of systemic mycoses. After oral administration of posaconazole, absolute bioavailability has been estimated to range from 8% to 47%. Pharmaceutical co-crystallization is a promising approach for improving dissolution rate or manipulating other physical properties of API. The objective of this study is to improve the dissolution rate of posaconazole by co-crystallization. A 1:1 stoichiometric co-crystals of adipic acid were prepared by solvent assisted grinding method. The prepared co-crystals were subjected to solid-state characterization by FTIR, PXRD and DSC studies. The physicochemical properties of posaconazole and co-crystals were assessed in terms of melting point, flowability and dissolution rate. The results indicated improvement in flow property and dissolution rate. In vitro dissolution profile of co-crystals showed a significant increased dissolution of posaconazole from initial period in 0.1 N hydrochloric acid solution. The dissolution efficiency for posaconazole-adipic acid co-crystal was 61.65 % against posaconazole, 46.58 %. Thus, co-crystallization can be a promising approach to prepare posaconazole-adipic acid co-crystals with improved physicochemical properties.


Assuntos
Administração Oral , Cristalização/instrumentação , Ácido Clorídrico , Entorses e Distensões/diagnóstico , Leveduras/classificação , Técnicas In Vitro/métodos , Preparações Farmacêuticas , Disponibilidade Biológica , Espectroscopia de Infravermelho com Transformada de Fourier , Eficiência , Dissolução , Micoses/patologia
15.
Front Immunol ; 12: 760095, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34912336

RESUMO

Talaromyce marneffei is an important thermally dimorphic pathogen causing disseminated mycoses in immunocompromised individuals in southeast Asia. Previous studies have suggested that NLRP3 inflammasome plays a critical role in antifungal immunity. However, the mechanism underlying the role of NLRP3 inflammasome activation in host defense against T. marneffei remains unclear. We show that T. marneffei yeasts but not conidia induce potent IL-1ß production. The IL-1ß response to T. marneffei yeasts is differently regulated in different cell types; T. marneffei yeasts alone are able to induce IL-1ß production in human PBMCs and monocytes, whereas LPS priming is essential for IL-1ß response to yeasts. We also find that Dectin-1/Syk signaling pathway mediates pro-IL-1ß production, and NLRP3-ASC-caspase-1 inflammasome is assembled to trigger the processing of pro-IL-1ß into IL-1ß. In vivo, mice deficient in NLRP3 or caspase-1 exhibit higher mortality rate and fungal load compared to wild-type mice after systemic T. marneffei infection, which correlates with the diminished recruitment of CD4 T cells into granulomas in knockout mice. Thus, our study first demonstrates that NLRP3 inflammasome contributes to host defense against T. marneffei infection.


Assuntos
Inflamassomos/imunologia , Micoses/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Infecções Oportunistas/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Caspase 1/genética , Feminino , Humanos , Inflamassomos/genética , Interleucina-1beta/imunologia , Lectinas Tipo C/imunologia , Leucócitos Mononucleares/imunologia , Fígado/imunologia , Fígado/microbiologia , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Micoses/microbiologia , Micoses/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Infecções Oportunistas/microbiologia , Infecções Oportunistas/patologia , Baço/microbiologia , Talaromyces
16.
STAR Protoc ; 2(4): 100963, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34849488

RESUMO

Epithelia provide the first line of defense against foreign pathogens, and disruption of tissue homeostasis frequently allows for opportunistic infections. Here we provide a protocol for induction of epithelial cell loss in zebrafish larvae, followed by infection with fungal pathogens. Details are provided for monitoring larval survival after infection, assessment of fungal burden, and prophylactic treatment with antifungal compounds. Limitations of the protocol include potential antifungal toxicity and high fungal inoculums to induce lethal infection with some pathogenic fungal species. For complete details on the use and execution of this protocol, please refer to Wurster et al. (2021).


Assuntos
Modelos Animais de Doenças , Células Epiteliais/patologia , Larva/microbiologia , Micoses , Peixe-Zebra/microbiologia , Animais , Antifúngicos/uso terapêutico , Micoses/tratamento farmacológico , Micoses/microbiologia , Micoses/patologia
17.
Microbiol Spectr ; 9(2): e0104821, 2021 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-34704799

RESUMO

The fungus Nosema bombycis causes significant economic losses via parasitism of an economically important insect. MicroRNAs (miRNAs) play important roles in regulating host and parasite gene expression via mRNA degradation or by inhibiting protein translation. To investigate whether microRNA-like RNAs (milRNAs) regulate N. bombycis pathogenesis and to better understand the regulatory mechanisms underlying infection, we constructed small RNA libraries from N. bombycis hyphae during the schizont proliferation period. Eleven novel milRNAs were determined by RNA sequencing and stem-loop reverse transcriptase PCR (RT-PCR) assays. Moreover, a virulence-associated milRNA, Nb-milR8, was identified as critical for N. bombycis proliferation by binding and downregulating expression of its target gene, BmPEX16, in the host during infection. Silencing of Nb-milR8 or overexpression of the target BmPEX16 gene resulted in increased susceptibility of Bombyx mori to N. bombycis infection. Taken together, these results suggest that Nb-milR8 is an important virulence factor that acts as an effector to suppress host peroxidase metabolism, thereby facilitating N. bombycis proliferation. These results provide important novel insights into interactions between pathogenic fungi and their hosts. IMPORTANCE A thorough understanding of fungal pathogen adaptations is essential for treating fungal infections. Recent studies have suggested that the role of small RNAs expressed in fungal microsporidia genomes are important for elucidating the mechanisms of fungal infections. Here, we report 11 novel microRNA-like RNAs (milRNAs) from the fungal microsporidium Nosema bombycis and identified NB-milRNAs that adaptively regulate N. bombycis proliferation. In addition, we demonstrate that N. bombycis modulates small RNA (sRNA)-mediated infection by encoding an Nb-miR8 that downregulates the expression of the host peroxidase metabolism protein BmPEX16, which is essential for peroxisome membrane biogenesis and peroxisome assembly. These results significantly contribute to our understanding of the pathogenic mechanisms of fungi, and especially microsporidia, while providing important targets for genetical engineering-based treatment of microsporidia.


Assuntos
Bombyx/microbiologia , Proteínas Fúngicas/biossíntese , Proteínas de Membrana/biossíntese , MicroRNAs/genética , Nosema/genética , Peroxidase/metabolismo , Animais , Bombyx/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/genética , Proteínas de Membrana/genética , Micoses/patologia , Nosema/crescimento & desenvolvimento , Nosema/patogenicidade , Peroxissomos/metabolismo , RNA Fúngico/genética
19.
Sci Rep ; 11(1): 17383, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34462470

RESUMO

Amphibian chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), has caused the greatest known loss of biodiversity due to an infectious disease. We used Bd infection data from quantitative real-time PCR (qPCR) assays of amphibian skin swabs collected across Chile during 2008-2018 to model Bd occurrence with the aim to determine bioclimatic and anthropogenic variables associated with Bd infection. Also, we used Bd presence/absence records to identify geographical Bd high-risk areas and compare Bd prevalence and infection loads between amphibian families, ecoregions, and host ecology. Data comprised 4155 Bd-specific qPCR assays from 162 locations across a latitudinal gradient of 3700 km (18º to 51ºS). Results showed a significant clustering of Bd associated with urban centres and anthropogenically highly disturbed ecosystems in central-south Chile. Both Bd prevalence and Bd infection loads were higher in aquatic than terrestrial amphibian species. Our model indicated positive associations of Bd prevalence with altitude, temperature, precipitation and human-modified landscapes. Also, we found that macroscale drivers, such as land use change and climate, shape the occurrence of Bd at the landscape level. Our study provides with new evidence that can improve the effectiveness of strategies to mitigate biodiversity loss due to amphibian chytridiomycosis.


Assuntos
Anfíbios/microbiologia , Batrachochytrium/genética , Altitude , Animais , Batrachochytrium/isolamento & purificação , Chile , DNA Fúngico/análise , DNA Fúngico/metabolismo , Ecossistema , Modelos Lineares , Micoses/epidemiologia , Micoses/microbiologia , Micoses/patologia , Micoses/veterinária , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Análise Espacial , Temperatura
20.
mBio ; 12(4): e0159421, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34425700

RESUMO

Invasive infections with emerging yeasts such as Geotrichum, Saprochaete/Magnusiomyces, Trichosporon, and other species are associated with high morbidity and mortality rates. Due to the rarity and heterogeneity of these yeasts, medical mycology has lacked guidance in critical areas affecting patient management. Now, physicians and life scientists from multiple disciplines and all world regions have united their expertise to create the "Global guideline for the diagnosis and management of rare yeast infections: an initiative of the European Confederation of Medical Mycology in cooperation with the International Society for Human and Animal Mycology and the American Society for Microbiology." Recommendations are stratified for high- and low-resource settings and are therefore applicable worldwide. The advantages and disadvantages of various diagnostic methods and treatment options are outlined. This guideline reflects the current best-practice management for invasive rare yeast infections in a range of settings, with the intent of establishing a global standard of care for laboratorians and clinicians alike.


Assuntos
Micoses/diagnóstico , Doenças Raras/diagnóstico , Doenças Raras/microbiologia , Antifúngicos/uso terapêutico , Humanos , Micologia/métodos , Micoses/tratamento farmacológico , Micoses/patologia
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