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2.
G3 (Bethesda) ; 10(9): 3417-3433, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32727924

RESUMO

Research into secondary metabolism (SM) production by fungi has resulted in the discovery of diverse, biologically active compounds with significant medicinal applications. The fungi rich in SM production are taxonomically concentrated in the subkingdom Dikarya, which comprises the phyla Ascomycota and Basidiomycota. Here, we explore the potential for SM production in Mucoromycota and Zoopagomycota, two phyla of nonflagellated fungi that are not members of Dikarya, by predicting and identifying core genes and gene clusters involved in SM. The majority of non-Dikarya have few genes and gene clusters involved in SM production except for the amphibian gut symbionts in the genus Basidiobolus Basidiobolus genomes exhibit an enrichment of SM genes involved in siderophore, surfactin-like, and terpene cyclase production, all these with evidence of constitutive gene expression. Gene expression and chemical assays also confirm that Basidiobolus has significant siderophore activity. The expansion of SMs in Basidiobolus are partially due to horizontal gene transfer from bacteria, likely as a consequence of its ecology as an amphibian gut endosymbiont.


Assuntos
Entomophthorales , Transferência Genética Horizontal , Anfíbios , Animais , Fungos , Filogenia , Metabolismo Secundário
3.
J Vet Intern Med ; 34(5): 2091-2095, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32681715

RESUMO

A 7-year-old castrated male French Bulldog was examined for chronic large intestinal enteropathy. A colonic mass and thickened rectal mucosa were identified, and histopathologic examination of endoscopic biopsy specimens disclosed eosinophilic proctitis with large (5-20 µm), irregularly shaped, pauciseptate hyphae that were Gomori methenamine silver and periodic acid-Schiff positive. Amplification and sequencing of ribosomal DNA extracted from paraffin-embedded tissues yielded a sequence with 97% identity to GenBank sequences for Basidiobolus ranarum. After itraconazole, terbinafine, and prednisone administration, clinical signs resolved rapidly, and sonographic lesions were largely absent after 6 weeks. Treatment was discontinued by the owner 15 weeks after diagnosis. Three weeks later, the dog collapsed acutely and was euthanized. Necropsy identified metastatic islet cell carcinoma and grossly unremarkable colorectal tissues. However, histopathology of the rectum disclosed multifocal submucosal granulomas with intralesional hyphae morphologically similar to those previously observed. This report is the first to describe medical treatment of gastrointestinal basidiobolomycosis in a dog.


Assuntos
Neoplasias Colorretais , Doenças do Cão , Entomophthorales , Zigomicose , Animais , Neoplasias Colorretais/veterinária , Doenças do Cão/diagnóstico , Doenças do Cão/tratamento farmacológico , Cães , Masculino , Zigomicose/diagnóstico , Zigomicose/tratamento farmacológico , Zigomicose/veterinária
4.
Fitoterapia ; 146: 104671, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32565347

RESUMO

Two new cyclopentapeptides, basidiosins A and B (1 and 2) were isolated from the mycelia extracts of entomophthoralean fungus Basidiobolus meristosporus RCEF 4516. The structures were determined based on spectroscopic methods, and the absolute config urations were assigned by Marfey's method on their acid hydrolyzates. Compounds 1 and 2 were identified as cyclo(L-Thr-L-Leu- L-Ile-D-Tyr-D-Thr) and cyclo(L-Thr-L-Leu-L-Val-D-Val-D-Ser), respectively. They were evaluated for the biological activities including antibacterial, antifungal and antioxidative activities. Furthermore, the biosynthetic pathway of 1 was proposed by bioinformatic analysis. This is the first study on the isolation of natural products from Basidiobolus fungus.


Assuntos
Produtos Biológicos/farmacologia , Entomophthorales/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Produtos Biológicos/isolamento & purificação , China , Entomophthorales/genética , Florestas , Estrutura Molecular , Família Multigênica , Micélio/química , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/farmacologia , Microbiologia do Solo
5.
Indian J Pathol Microbiol ; 63(2): 270-272, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32317530

RESUMO

Basidiobolus ranarum is an uncommon pathogen in ocular infections. It has been previously reported from subcutaneous and gastrointestinal infections. Here, we report a rare case of ocular infection caused by B. ranarum. A 21-year-old male patient presented with visual loss and pain in the right eye due to corneal abscess following an injury while welding. KOH mount performed was indicative of fungal hyphae. Fungal culture revealed growth of B. ranarum. Meanwhile, the patient was treated with antifungal (topical natamycin and oral ketoconazole) along with total corneal transplantation. B. ranarum is a fungus very uncommonly causing ocular pathogenesis. This results in diagnostic confusion leading to poor treatment outcomes. Hence, a mycology laboratory has to be aware about this fungus and need to consider it as a differential diagnosis in patients with infectious corneal abscess.


Assuntos
Entomophthorales/patogenicidade , Oftalmopatias/diagnóstico , Oftalmopatias/microbiologia , Olho/microbiologia , Zigomicose/diagnóstico , Abscesso/diagnóstico , Antifúngicos/uso terapêutico , Córnea/patologia , Diagnóstico Diferencial , Olho/efeitos dos fármacos , Oftalmopatias/tratamento farmacológico , Humanos , Masculino , Adulto Jovem , Zigomicose/tratamento farmacológico , Zigomicose/microbiologia
6.
Am Nat ; 195(3): 504-523, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32097039

RESUMO

In deterministic models of epidemics, there is a host abundance threshold above which the introduction of a few infected individuals leads to a severe epidemic. Studies of weather-driven animal pathogens often assume that abundance thresholds will be overwhelmed by weather-driven stochasticity, but tests of this assumption are lacking. We collected observational and experimental data for a fungal pathogen, Entomophaga maimaiga, that infects the gypsy moth, Lymantria dispar. We used an advanced statistical-computing algorithm to fit mechanistic models to our data, such that different models made different assumptions about the effects of host density and weather on E. maimaiga epizootics (epidemics in animals). We then used Akaike information criterion analysis to choose the best model. In the best model, epizootics are driven by a combination of weather and host density, and the model does an excellent job of explaining the data, whereas models that allow only for weather effects or only for density-dependent effects do a poor job of explaining the data. Density-dependent transmission in our best model produces a host density threshold, but this threshold is strongly blurred by the stochastic effects of weather. Our work shows that host-abundance thresholds may be important even if weather strongly affects transmission, suggesting that epidemiological models that allow for weather have an important role to play in understanding animal pathogens. The success of our model means that it could be useful for managing the gypsy moth, an important pest of hardwood forests in North America.


Assuntos
Entomophthorales/fisiologia , Controle de Insetos , Larva/microbiologia , Mariposas/microbiologia , Tempo (Meteorologia) , Animais , Larva/crescimento & desenvolvimento , Modelos Biológicos , Mariposas/crescimento & desenvolvimento , Densidade Demográfica , Processos Estocásticos
7.
Artigo em Inglês | MEDLINE | ID: mdl-31952125

RESUMO

Basidiobolomycosis is an uncommon emerging fungal infection caused by Basidiobolus ranarum. It frequently causes cutaneous infection, but it rarely infects visceral tissues in humans. Here, a 39-year-old previously healthy woman presented with severe left-sided abdominal pain and weight loss. She had visited several hospitals and had provisionally been diagnosed as having either a retroperitoneal malignancy or retroperitoneal fibrosis before being referred to our hospital. Abdominal computerized tomography and biopsy of the retroperitoneal mass revealed retroperitoneal basidiobolomycosis infection. She was started on antifungal treatment. This led to significant improvement, without surgical intervention. Gastrointestinal basidiobolomycosis can present in many forms, commonly involving the colon and liver with multifocal inflammatory masses. Nonetheless, retroperitoneal basidiobolomycosis presentation is extremely rare and should be considered in the differential diagnosis of a retroperitoneal mass with eosinophilia.


Assuntos
Entomophthorales , Fibrose Retroperitoneal/diagnóstico , Zigomicose/diagnóstico , Adulto , Antifúngicos/uso terapêutico , Diagnóstico Diferencial , Eosinofilia/diagnóstico , Feminino , Humanos , Zigomicose/tratamento farmacológico
8.
Med Mycol ; 58(2): 264-267, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31111900

RESUMO

Basidiobolus species were isolated from colonic biopsy samples of patients with gastrointestinal basidiobolomycosis (GIB) in southern Saudi Arabia. Isolated fungi were initially identified using classical mycological tools and confirmed by sequence analysis of the large subunit ribosomal RNA gene. Phenotypic tests revealed zygomycete-like fungi which conform to those of Basidiobolus species. Five sequenced strains formed a monophyletic clade in the 28S ribosomal RNA gene phylogenetic tree. They shared 99.97% similarity with B. haptosporus and 99.97% with B. haptosporus var. minor, and relatively lower similarity with B. ranarum (99.925%). The study suggests a new and a serious causal agent of GIB related to Basidiobolus haptosporus. These isolates are not related to B. ranarum, which is commonly linked to this disease.


Assuntos
Colo/microbiologia , Entomophthorales/classificação , Filogenia , Zigomicose/microbiologia , Biópsia , Colo/patologia , Entomophthorales/genética , Entomophthorales/patogenicidade , Gastroenteropatias/microbiologia , Humanos , RNA Ribossômico 28S/genética , Arábia Saudita , Zigomicose/diagnóstico
9.
Environ Entomol ; 48(5): 1214-1222, 2019 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-31501859

RESUMO

We collected data on mortality of late-instar gypsy moth, Lymantria dispar (L.), from outbreak populations over 4 wk in June 2017 at 10 sites in the New England region of the United States, along with estimated rainfall at these sites. Deposition of airborne conidia of the fungal pathogen, Entomophaga maimaiga Humber, Shimazu & R.S. Soper, was measured at these same sites as well as at seven other locations in New England. We also quantified the geographical distribution of gypsy moth-caused defoliation in New England in 2017 and 2018 from Landsat imagery. Weekly mortality of gypsy moth larvae caused by E. maimaiga correlated with local deposition of conidia from the previous week, but not with rainfall. Mortality from this pathogen reached a peak during the last 2 wk of gypsy moth larval development and always exceeded that caused by LdNPV, the viral pathogen of gypsy moth that has long been associated with gypsy moth outbreaks, especially prior to 1989. Cotesia melanoscela (Ratzeburg) was by far the most abundant parasitoid recovered and caused an average of 12.6% cumulative parasitism, but varied widely among sites. Deposition of E. maimaiga conidia was highly correlated with percent land area defoliated by gypsy moths within distances of 1 and 2 km but was not significantly correlated with defoliation at distances greater than 2 km. This is the first study to relate deposition of airborne conidia of E. maimaiga to mortality of gypsy moths from that agent.


Assuntos
Entomophthorales , Mariposas , Animais , Larva , Esporos Fúngicos
10.
Curr Opin Insect Sci ; 33: 91-98, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31358202

RESUMO

Pandora neoaphidis and Entomophthora planchoniana are widespread and important specialist fungal pathogens of aphids in cereals (Sitobion avenae and Rhopalosiphum padi). The two aphid species share these pathogens and we compare factors influencing susceptibility and resistance. Among factors that may influence susceptibility and resistance are aphid behavior, conspecific versus heterospecific host, aphid morph, life cycle, and presence of protective endosymbionts. It seems that the conspecific host is more susceptible (less resistant) than the heterospecific host, and alates are more susceptible than apterae. We conceptualize the findings in a diagram showing possible transmission in field situations and we pinpoint where there are knowledge gaps.


Assuntos
Afídeos/microbiologia , Entomophthorales/patogenicidade , Animais , Afídeos/fisiologia , Feminino , Estágios do Ciclo de Vida , Poaceae , Simbiose
11.
Curr Opin Insect Sci ; 33: 99-104, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31358203

RESUMO

Social insects are distinguished by their lifestyle of living in groups with division of labour, cooperative brood care, and reproduction limited to a few colony members. Social insects often build large colonies with remarkable densities of highly related individuals and this can lead to an increased pathogen pressure. Our review focuses on interactions of ants with two important taxonomic groups of fungi infecting ants: Hypocreales (Ascomycota) and Entomophthorales (Entomophthoromycotina), and their different infection strategies, including host manipulation for optimal spore dispersal in the specialised ant pathogens. In social insects such as ants, resistance to pathogens is present at the colony level, with social immunity in addition to the individual resistance. We describe how ants use both organizational and behavioural defence strategies to combat fungal pathogens, with emphasis on highly specialised fungi from the genera Ophiocordyceps and Pandora.


Assuntos
Formigas/microbiologia , Comportamento Social , Animais , Formigas/fisiologia , Comportamento Animal/fisiologia , Entomophthorales , Hypocreales
12.
PLoS One ; 14(5): e0215914, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31116738

RESUMO

Entomophthoralean fungi are insect pathogenic fungi and are characterized by their active discharge of infective conidia that infect insects. Our aim was to study the effects of temperature on the discharge and to characterize the variation in the associated temporal pattern of a newly discovered Pandora species with focus on peak location and shape of the discharge. Mycelia were incubated at various temperatures in darkness, and conidial discharge was measured over time. We used a novel modification of a statistical model (pavpop), that simultaneously estimates phase and amplitude effects, into a setting of generalized linear models. This model is used to test hypotheses of peak location and discharge of conidia. The statistical analysis showed that high temperature leads to an early and fast decreasing peak, whereas there were no significant differences in total number of discharged conidia. Using the proposed model we also quantified the biological variation in the timing of the peak location at a fixed temperature.


Assuntos
Entomophthorales/fisiologia , Modelos Estatísticos , Esporos Fúngicos/fisiologia
14.
New Microbiol ; 42(2): 125-128, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30994179

RESUMO

Gastrointestinal basidiobolomycosis (GIB), an unusual fungal infection caused by the fungus Basidiobolus ranarum, is rarely reported in the medical literature. GIB is difficult to diagnose because its clinical presentation is non-specific and has no identifiable risk factors. We report here the first case of GIB diagnosed in Italy in a patient suffering from a duodenal ulcer with perforation. The patient was successfully treated with itraconazole. The absence of non-specific signs and symptoms of GIB may delay a definitive diagnosis and treatment. A microbiological investigation should always be requested in order to reach a rapid and definitive diagnosis and to rule out other intestinal diseases.


Assuntos
Úlcera Duodenal , Entomophthorales , Zigomicose , Idoso , Antifúngicos/uso terapêutico , Úlcera Duodenal/complicações , Humanos , Itália , Itraconazol/uso terapêutico , Masculino , Úlcera Péptica Perfurada/complicações , Resultado do Tratamento , Zigomicose/complicações , Zigomicose/diagnóstico , Zigomicose/tratamento farmacológico
15.
Vet Clin Pathol ; 48(1): 83-88, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30897244

RESUMO

A 2-year-old female spayed Boxer dog was presented for a 1-month history of progressive hemorrhagic diarrhea with tenesmus and weight loss despite trial courses of antibiotics and diet change. Abdominal ultrasound revealed severe, focal thickening, and loss of normal architecture of the colonic wall with abdominal lymphadenomegaly. Dry-mount fecal cytology, performed on several consecutive days, consistently revealed numerous, round, 16-20 µm structures with basophilic, granular content, and a thin cell wall. Transmission electron microscopy identified these structures as fungi. Culture, polymerase chain reaction (PCR), and sequencing of the internal transcribed spacer, D1/D2 regions, and DNA-directed RNA polymerase II core subunit (RPB2) confirmed the presence of Basidiobolus microsporus in the feces. Biopsies collected via ileocolonoscopy revealed marked, multifocal, chronic, neutrophilic, and eosinophilic ileitis and colitis with ulceration, granulation tissue, and intralesional hyphae (identified with Gomori methenamine silver stain). A Pythium enzyme-linked immunosorbent assay and Pythium-specific PCR performed on the formalin-fixed paraffin-embedded biopsy specimens were positive while Basidiobolus-specific PCR was negative, thus confirming a diagnosis of pythiosis. This report describes a fatal case of colonic and intestinal pythiosis with the presence of fecal Basidiobolus sp. spores, suggestive of concurrent gastrointestinal basidiobolomycosis.


Assuntos
Coinfecção/veterinária , Doenças do Cão/microbiologia , Entomophthorales , Gastroenteropatias/veterinária , Pitiose/diagnóstico , Pythium , Zigomicose/veterinária , Animais , Coinfecção/diagnóstico , Coinfecção/microbiologia , Coinfecção/patologia , Doenças do Cão/diagnóstico , Doenças do Cão/patologia , Cães , Feminino , Gastroenteropatias/diagnóstico , Gastroenteropatias/microbiologia , Gastroenteropatias/patologia , Pitiose/complicações , Pitiose/microbiologia , Pitiose/patologia , Zigomicose/complicações , Zigomicose/diagnóstico , Zigomicose/patologia
16.
BMJ Case Rep ; 12(1)2019 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-30700449

RESUMO

Basidiobolomycosis is a rare fungal infection that may affect the gastrointestinal tract. It is caused by Basidiobolus ranarum and less than 80 cases have been reported in the literature. The incidence seems to be higher in the Middle East and in particular Saudi Arabia where most cases are diagnosed in the south-western region. An 18-year-old woman presented to the emergency department with an obstructing caecal mass initially suspected to be malignant. Surgical resection was complicated by bowel perforation, histology and cultures confirmed basidiobolomycosis infection. The postoperative course was complicated by an enterocutaneous fistula, fungal intra-abdominal abscesses, liver and lung abscesses, formation of mycotic hepatic artery aneurysm and meningoencephalitis. The patient eventually expired due to sepsis despite aggressive treatment. Diagnosis and management of such rare cases are very challenging and require a multidisciplinary approach. Complications are common and associated with a high mortality.


Assuntos
Aneurisma Infectado/complicações , Neoplasias do Colo , Entomophthorales/isolamento & purificação , Obstrução Intestinal/complicações , Perfuração Intestinal/complicações , Zigomicose/complicações , Adolescente , Aneurisma Infectado/diagnóstico por imagem , Aneurisma Infectado/microbiologia , Diagnóstico Diferencial , Evolução Fatal , Feminino , Trato Gastrointestinal/diagnóstico por imagem , Trato Gastrointestinal/microbiologia , Humanos , Obstrução Intestinal/diagnóstico por imagem , Perfuração Intestinal/diagnóstico , Intestinos , Arábia Saudita , Sepse/complicações , Sepse/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Zigomicose/diagnóstico
19.
J Mycol Med ; 29(1): 75-79, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30553627

RESUMO

Gastrointestinal basidiobolomycosis (GIB), a rare fungal infection associated with high mortality, has been reported worldwide mainly from tropical and subtropical regions of Asia, USA, and Latin America. The clinical manifestations are highly diverse and non-specific depending on the underlying disease, but fever, abdominal pain, weight loss, diarrhea, constipation and chills have been observed. There are no prominent risk factors for GIB but climatic conditions and life style are related to this infection in arid and semi-arid regions. Therefore timely diagnosis and early treatment is a challenge. Herein, we present an unusual case of gastrointestinal basidiobolomycosis in a 54-year-old male, initially misdiagnosed as colon cancer. After follow-up, no evidence of relapse and the patient was successfully cured by liposomal amphotericin B. In addition, the differential diagnosis and histopathological findings are discussed with a review of the literature.


Assuntos
Entomophthorales/isolamento & purificação , Zigomicose/diagnóstico , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Neoplasias do Colo/diagnóstico , Diagnóstico Diferencial , Erros de Diagnóstico , Diarreia/etiologia , Trato Gastrointestinal/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Zigomicose/tratamento farmacológico
20.
Mycoses ; 62(3): 298-305, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30411397

RESUMO

Members of the genus Basidiobolus are potentially pathogenic fungi, known to cause mycoses in tropical and subtropical countries. Basidiobolus spp. can be associated with animals, and reptiles and amphibians are candidate vectors for the distribution of this fungus. The presence of Basidiobolus spp. was described for different reptiles in several African countries, although not for South Africa. In addition, quantitative data are scarce. The aim of this study was to analyse faeces of selected South African reptiles for the presence and quantity of "viable Basidiobolus units." Faecal samples of gecko and agama lizards were collected and analysed using spread plating, with confirmation by PCR. The addition of dichloran and benomyl to standard fungal media improved the selectivity and allowed quantification of Basidiobolus spp. in reptile faeces. The amount of Basidiobolus spp. varied between 300 and 1.4 × 106  CFU per gram of pooled gecko faeces, which mostly corresponds to >1000 CFU per outside dropping and <100 CFU per inside dropping. About 60% of analysed agama faeces carried Basidiobolus spp., ranging from 150 to 1.2 × 105  CFU per dropping. Our results show for the first time that faeces of South African reptiles frequently carry Basidiobolus spp., confirming that they can contribute to the distribution of this fungus.


Assuntos
Entomophthorales/isolamento & purificação , Fezes/microbiologia , Répteis/microbiologia , Animais , Contagem de Colônia Microbiana , Meios de Cultura/química , Entomophthorales/genética , Entomophthorales/crescimento & desenvolvimento , Reação em Cadeia da Polimerase , África do Sul
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