Mycotic keratitis due to Aspergillus nomius.
Ontology highlight
ABSTRACT:
SUBMITTER: Manikandan P
PROVIDER: S-EPMC2756917 | biostudies-literature | 2009 Oct
REPOSITORIES: biostudies-literature
Publications
Mycotic keratitis due to Aspergillus nomius.
Manikandan Palanisamy P Varga János J Kocsubé Sándor S Samson Robert A RA Anita Raghavan R Revathi Rajaraman R Dóczi Ilona I Németh Tibor Mihály TM Narendran Venkatapathy V Vágvölgyi Csaba C Manoharan Chockaiya C Kredics László L
Journal of clinical microbiology 20090826 10
We report the first known case of fungal keratitis caused by Aspergillus nomius. Ocular injury was known as a predisposing factor. The patient was treated with natamycin and econazole eye drops, itraconazole eye ointment, and oral ketoconazole. A therapeutic penetrating keratoplasty was performed 16 days after presentation. A sequence-based approach was used to assign the isolate to a species. ...[more]
Similar Datasets
Project description:Mycotic keratitis is a distressing infection and may lead to permanent blindness. Fifty two cases of suspected mycotic keratitis were studied from Jan 91 to Sep 94. Specimens were collected on swabs in 20 cases and by corneal scraping in 32 cases. Wet mount examination of the specimens revealed fungal elements in 8 (15.4%) cases, of which 3 specimens were collected on swabs and 5 by corneal scraping. Fungi were isolated from a total of 12 (23.1%) specimens 5 of which were obtained by swabs while 7 by corneal scraping. Important pathogens were Fusarium spp, Aspergillus spp, Candida albicans and Cephalosporium spp. Direct examination of the specimens was found to be less sensitive than culture for the diagnosis of mycotic keratitis.
| S-EPMC5530211 | biostudies-other
Project description:BackgroundAspergillus nomius is an opportunistic pathogen and one of the three most important producers of aflatoxins in section Flavi. This fungus has been reported to contaminate agricultural commodities, but it has also been sampled in non-agricultural areas so the host range is not well known. Having a similar mycotoxin profile as A. parasiticus, isolates of A. nomius are capable of secreting B- and G- aflatoxins.ResultsIn this study we discovered that the A. nomius type strain (NRRL 13137) has a genome size of approximately 36 Mb which is comparable to other Aspergilli whose genomes have been sequenced. Its genome encompasses 11,918 predicted genes, 72% of which were assigned GO terms using BLAST2GO. More than 1,200 of those predicted genes were identified as unique to A. nomius, and the most significantly enriched GO category among the unique genes was oxidoreducatase activity. Phylogenomic inference shows NRRL 13137 as ancestral to the other aflatoxigenic species examined from section Flavi. This strain contains a single mating-type idiomorph designated as MAT1-1.ConclusionsThis study provides a preliminary analysis of the A. nomius genome. Given the recently discovered potential for A. nomius to undergo sexual recombination, and based on our findings, this genome sequence provides an additional evolutionary reference point for studying the genetics and biology of aflatoxin production.
| S-EPMC4515932 | biostudies-literature
Project description:In recent years, the well-known plant pathogens of the Colletotrichum genus were increasingly reported to cause ophthalmic infections in humans. Among 66 species in the Colletotrichum genus, only a few are known to be pathogenic for humans. We report here five cases of ophthalmic infections due to Colletotrichum truncatum, a species never reported earlier to cause human infection. The isolates were identified by morphological characteristics and the sequencing of internal spacer regions of ribosomal DNA. The progress of lesions in those patients was slow compared to that of lesions caused by Aspergillus or Fusarium infections. The surgical management included total penetrating keratoplasty in patients with keratitis and pars plana vitrectomy in endophthalmitis. Two patients were treated additionally with intravitreal amphotericin B deoxycholate, one patient with oral itraconazole, and another patient with oral and topical fluconazole therapy. The present series therefore highlights the expanding spectrum of agents causing eye infections and the inclusion of C. truncatum as a human pathogen.
| S-EPMC3147767 | biostudies-literature
Project description:Background and purposeHerein, we report the first case of fungal keratitis due to Aspergillus minisclerotigenes in a 68-year-old rural woman admitted to the Ophthalmology Center of Khatam-Al-Anbia Hospital in Mashhad, northeast of Iran.Case reportThe patient presented with severe pain, burning, foreign body sensation, and reduced vision in her right eye. She had long-term uncontrolled diabetes and was not able to close her eye due to an anatomical problem with the eyelid. The cornea smear sample was cultured, and the fungus was initially identified as Aspergillus flavus. The isolated strain was further identified by sequencing a part of the calmodulin gene as A. minisclerotigenes. The patient did not respond to any antifungal treatments (e.g., amphotericin B and voriconazole drops, and fluconazole 300 mg/day); therefore, she was eventually subjected to corneal transplantation surgery.ConclusionFungal keratitis can be caused by the less common species. The reliable identification of the causative agents can be accomplished by the implementation of molecular methods.
| S-EPMC6626709 | biostudies-literature
Project description:We report two cases of keratitis caused by a rare fungus Myrothecium species. Clinical presentation, identification, and management were studied. Both fungi were grown from corneal scraping and identified as M. verrucaria and M. gramineum based on the microbiological techniques and DNA sequencing analysis. Both patients were treated with topical natamycin and or voriconazole/econazole. In the first patient, there was total healing of the with scar formation, however, the prognosis was poor in the second patient.
| S-EPMC6702144 | biostudies-literature
Project description:A male patient presented with complaints of redness, pain and defective vision in the left eye. The infiltrate healed completely after two weeks of topical natamycin administration. A polyphasic approach was used to identify the isolate as Aspergillus pseudotamarii, which produced aflatoxins in inducing medium.
| S-EPMC3885925 | biostudies-literature
Project description:PurposeTo document the clinical profile of patients with keratitis due to Aspergillus flavus and to elaborate on differences in the aflatoxin-producing potential of keratitis strains versus environmental strains of A. flavus.MethodsOver a 6-month period, strains of Aspergillus flavus were isolated in culture from corneal scrape or biopsy material of patients who presented with suppurative keratitis (clinical isolates). The strains were confirmed to be A. flavus by molecular methods (amplification of the internal transcribed spacer 2 [ITS 2] region and direct sequencing followed by comparative GenBank analysis). The aflatoxin-producing potential of each strain was determined by thin-layer chromatography. The ability of each strain to form sclerotia in Czapek-Dox agar (CDA) after 7 days incubation at 30 degrees C in the dark and to produce a beige ring in yeast extract sucrose agar supplemented with methyl beta-cyclodextrin and sodium desoxycholate (YESD medium) after 3 days incubation at 30 degrees C was also assessed. For comparison, the tests were also run on 10 strains of A. flavus (identity confirmed by molecular methods) collected from local farming areas (environmental isolates).ResultsAflatoxin B1 was detected in 16 (80%) of 20 culture filtrate or mycelial homogenate samples of the clinical isolates (mean concentration: 366.7+/-125.4 parts per billion [ppb]) but in only eight (40%) of 20 samples of environmental isolates (mean concentration: 306.6+/-125.4 ppb). Seven of the eight aflatoxin-producing clinical isolates and two of the four aflatoxin-producing environmental isolates formed sclerotia (>400 microm) and a beige ring in culture.ConclusionsAflatoxin B1 was detected in a significantly higher percentage of growth samples of clinical isolates (80%) than growth samples of environmental isolates (40%) (chi(2)=6.667; p=0.0098); the therapeutic implications of this finding require further study. The production of sclerotia and a beige ring in culture appear to be useful markers of aflatoxin-producing potential in strains of A. flavus isolated from keratitis.
| S-EPMC2866576 | biostudies-literature
Project description:Aspergillus flavus and Fusarium solani are the predominant causative agents of mycotic keratitis in the tropical part of the world. Tear proteins play a major role in the innate immune response against these fungal infections as has been shown by the presence of complement proteins and neutrophil extracellular trap proteins in keratitis patients tear. In this study, we established the presence of the components of the alternate pathway of complement system and their functional state in the tear film of mycotic keratitis patients. The complement proteins namely, C3 and CFH were found only in the open-eye tear of patients but not in control individuals. In vitro analysis showed binding of purified C3b and CFH to fungal spores, which confirmed that the spores can provide a foreign surface for forming the complement complex. Analysis of spore bound tear proteins by mass spectrometry exhibited the presence of known proteins of the alternate pathway complement cascade in keratitis patient tear. Hemolytic assay using rabbit RBC confirmed the presence of a functional alternate pathway of complement cascade in the tear proteome of the patients. The presence of negative regulators, CFH and CFI, in the patient tear indicate that the complement activity is tightly regulated during fungal infection. Mass spectrometry data show vitronectin and clusterin, two known inhibitors of the membrane attack complex only in the patient tear. These data demonstrate the activation of the alternate pathway of complement cascade during the early stages of infection. Interestingly, the production of multiple negative regulators of complement cascade implies the pathogen can effectively evade the host complement system during infection.
| S-EPMC7218074 | biostudies-literature
Project description:Palmarosa essential oil (PEO) is an alternative to synthetic fungicides to control the contamination by food-deteriorating fungi, such as Aspergillus nomius. Nonetheless, the low long-term stability and volatility hamper its utilization. Thus, this study aimed to develop nanostructured lipid carriers (NLCs) containing PEO to improve its stability and consequently prolong the activity against A. nomius. A mixture design was applied to find the best preparation conditions for antifungal activity. The characterization analyses included size measurements, zeta potential (ζ-potential), entrapment efficiency (EE), and antifungal activity (by inhibition of mycelial growth (IMG) and/or in situ test (pre-contaminated Brazil nuts) tests). The nanocarriers presented particle sizes smaller than 300 nm, homogeneous size distribution, ζ-potential of -25.19 to -41.81 mV, and EE between 73.6 and 100%. The formulations F5 and F10 showed the highest IMG value (98.75%). Based on the regression model, three optimized formulations (OFs) were tested for antifungal activity (IMG and in situ test), which showed 100% of inhibition and prevented the deterioration of Brazil nuts by A. nomius. The preliminary stability test showed the maintenance of antifungal activity and physicochemical characteristics for 90 days. These results suggest a promising system as a biofungicide against A. nomius.
| S-EPMC8399424 | biostudies-literature
Project description:Sponge-derived fungi have recently attracted attention as an important source of interesting bioactive compounds. Aspergillus nomius NC06 was isolated from the marine sponge Neopetrosia chaliniformis. This fungus was cultured on rice medium and yielded four compounds including three new oxisterigmatocystins, namely, J, K, and L (1, 2, and 3), and one known compound, aspergillicin A (4). Structures of the compounds were elucidated by 1D and 2D NMR spectroscopy and by high-resolution mass spectrometry. The isolated compounds were tested for cytotoxic activity against HT 29 colon cancer cells, where compounds 1, 2, and 4 exhibited IC50 values of 6.28, 15.14, and 1.63 µM, respectively. Under the fluorescence microscope by using a double staining method, HT 29 cells were observed to be viable, apoptotic, and necrotic after treatment with the cytotoxic compounds 1, 2, and 4. The result shows that compounds 1 and 2 were able to induce apoptosis and cell death in HT 29 cells.
| S-EPMC8621937 | biostudies-literature