Rinosinusitis micótica alérgica con destrucción de base de cráneo / Allergic fungal rhinosinusitis with skull base destruction

La sinusitis micótica alérgica es una enfermedad inflamatoria de la mucosa rinosinusal producida por hongos que pueden aislarse de la cavidad de nasal de individuos sanos. Se produce indirectamente por los hongos que actúan como antígeno y desencadenan una reacción inmunológica mediada por IgE que origina pólipos y una secreción mucosa espesa con detritus e hifas denominada mucina. Su presentación clínica más frecuente es una sinusitis crónica unilateral o bilateral con pólipos. Con menos frecuencia, las sustancias originadas por la desgranulación de los eosinófilos producen remodelación o destrucción ósea y la sinusitis puede simular una neoplasia. Se describe el caso clínico de un paciente que padeció una sinusitis micótica alérgica con destrucción ósea masiva de la base del cráneo y que tuvo extensión intracraneal extradural e intraorbitaria de la enfermedad. Fue tratado con éxito mediante cirugía y corticoides. (AU)

Allergic fungal sinusitis is an inflammatory disease of the rhinosinusal mucosa caused by fungi that can be isolated from the nasal cavity of healthy individuals. The pathology is produced indirectly by the fungus that acts as an antigen and triggers an IgE-mediated allergic reaction that causes polyps and a thick mucous discharge with detritus and hyphae called mucin. Its most common clinical presentation is unilateral or bilateral chronic sinusitis with polyps. Less commonly, substances originated by the degranulation of eosinophils cause bone remodeling or destruction, and sinusitis can simulate a neoplasia. We describe the clinical case of a patient who suffered from allergic fungal sinusitis with massive bone destruction of the skull base and who had intracranial, extradural and intraorbital extension of the disease. He was successfully treated with surgery and corticosteroids.Key words: allergic fungal sinusitis, intracranial extension, endoscopic surgery, transorbital transpalpebral approach. (AU)

Evaluation of Seven Essential Oils as Seed Treatments against Seedborne Fungal Pathogens of Cucurbita maxima.

Essential oils are gaining interest as environmentally friendly alternatives to synthetic fungicides for management of seedborne pathogens. Here, seven essential oils were initially tested in vivo for disinfection of squash seeds (Cucurbita maxima) naturally contaminated by Stagonosporopsis cucurbitacearum, Alternaria alternata, Fusarium fujikuro, Fusarium solani, Paramyrothecium roridum, Albifimbria verrucaria, Curvularia spicifera, and Rhizopus stolonifer. The seeds were treated with essential oils from Cymbopogon citratus, Lavandula dentata, Lavandula hybrida, Melaleuca alternifolia, Laurus nobilis, and Origanum majorana (#1 and #2). Incidence of S. cucurbitacearum was reduced, representing a range between 67.0% in L. nobilis to 84.4% in O. majorana #2. Treatments at 0.5 mg/mL essential oils did not affect seed germination, although radicles were shorter than controls, except with C. citratus and O. majorana #1 essential oils. Four days after seeding, seedling emergence was 20%, 30%, and 10% for control seeds and seeds treated with C. citratus essential oil (0.5 mg/mL) and fungicides (25 g/L difenoconazole plus 25 g/L fludioxonil). S. cucurbitacearum incidence was reduced by ~40% for plantlets from seeds treated with C. citratus essential oil. These data show the effectiveness of this essential oil to control the transmission of S. cucurbitacearum from seeds to plantlets, and thus define their potential use for seed decontamination in integrated pest management and organic agriculture.

Curvularia lunata as new causal pathogen of tomato early blight disease in Egypt.

Tomato plants displaying early blight symptoms were collected from different localities in the provinces of Assiut and Sohag, Egypt. The causal pathogens were isolated on potato dextrose agar plates. Pathogenicity tests with 48 isolates were carried out under greenhouse conditions on tomato cultivar (CV 844). All tested isolates caused symptoms of early blight disease with different degrees. The highest disease severity on tomato plants was found after inoculation with isolate No. 6 followed by isolates No. 20 and No. 31. The most pathogenic isolates were identified by sequence analysis using ITS1 and ITS4 primers. The analysis of the amplified sequences from fungal isolates No. 6, 20 and 31 displayed 99-100% nucleotide identity with Alternaria solani, Curvularia lunata and A. alternata, respectively. To our knowledge, this is the first report of Curvularia lunata as one of the causal pathogens of early blight disease of tomato plants in Egypt.

The key iron assimilation genes ClFTR1, ClNPS6 were crucial for virulence of Curvularia lunata via initiating its appressorium formation and virulence factors.

Iron is virtually an essential nutrient for all organisms, to understand how iron contributes to virulence of plant pathogenic fungi, we identified ClFTR1 and ClNPS6 in maize pathogen Curvularia lunata (Cochliobolus lunatus) in this study. Disruption of ClNPS6 significantly impaired siderophore biosynthesis. ClFTR1 and ClNPS6 did mediate oxidative stress but had no significant impact on vegetative growth, conidiation, cell wall integrity and sexual reproduction. Conidial germination delayed and appressoria formation reduced in ΔClftr1 comparing with wild type (WT) CX-3. Genes responsible for conidial germination, appressoria formation, non-host selective toxin biosynthesis and cell wall degrading enzymes were also downregulated in the transcriptome of ΔClftr1 and ΔClnps6 compared with WT. The conidial development, toxin biosynthesis and polygalacturonase activity were impaired in the mutant strains with ClFTR1 and ClNPS6 deletion during their infection to maize. ClFTR1 and ClNPS6 were upregulated expression at 12-24 and 48-120 hpi in WT respectively. ClFTR1 positively regulated conidial germination, appressoria formation in the biotrophy-specific phase. ClNPS6 positively regulates non-host selective toxin biosynthesis and cell wall degrading enzyme activity in the necrotrophy-specific phase. Our results indicated that ClFTR1 and ClNPS6 were key genes of pathogen known to conidia development and virulence factors.

Curvularia eragrostidis, a new threat to large cardamom (Amomum subulatum Roxb.) causing leaf blight in Sikkim.

Large cardamom (Amomum subulatum Roxb.) is now affected by several diseases caused by both viruses and fungi. At present, leaf blight is considered a major threat to cardamom cultivation in Sikkim. During the past two decades, cultivation of the crop in this region has dropped by almost 60%. Hence, to quantify the severity of leaf blight damage and identification of the causal organism for the disease, a survey was conducted from May to August 2017 in different large cardamom growing regions of Sikkim. During this survey, a typical symptom of leaf blight was observed on cardamom leaves in many locations. The leaves with blights were collected, surface sterilized, and inoculated on potato dextrose agar (PDA). The pathogen was isolated as pure culture, and on the basis of morphological and microscopic characteristics, the fungus was identified species of Curvularia. Molecular characterization of the fungal isolate with ITS-rDNA partial gene amplification using universal primers (ITS4 and ITS5), showed 100% similarity with Curvularia eragrostidis (family: Pleosporaceae). The fungal isolate and nucleotide sequence was deposited in National Fungal Culture Collection of India (NFCCI), Pune and NCBI with accession numbers NFCCI 4541 and MN710527, respectively. This is the first report on the occurrence of C. eragrostidis pathogen causing leaf blight of large cardamom grown in Sikkim.