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Trichothecene mycotoxins are sesquiterpenoid compounds primarily produced by fungi in taxonomical genera such as Fusarium, Myrothecium, Stachybotrys, Trichothecium, and others, under specific climatic conditions on a worldwide basis. Fusarium mold is a major plant pathogen and produces a number of trichothecene mycotoxins including deoxynivalenol (or vomitoxin), nivalenol, diacetoxyscirpenol, and T-2 toxin, HT-2 toxin. Monogastrics are sensitive to vomitoxin, while poultry and ruminants appear to be less sensitive to some trichothecenes through microbial metabolism of trichothecenes in the gastrointestinal tract. Trichothecene mycotoxins occur worldwide however both total concentrations and the particular mix of toxins present vary with environmental conditions. Proper agricultural practices such as avoiding late harvests, removing overwintered stubble from fields, and avoiding a corn/wheat rotation that favors Fusarium growth in residue can reduce trichothecene contamination of grains. Due to the vague nature of toxic effects attributed to low concentrations of trichothecenes, a solid link between low level exposure and a specific trichothecene is difficult to establish. Multiple factors, such as nutrition, management, and environmental conditions impact animal health and need to be evaluated with the knowledge of the mycotoxin and concentrations known to cause adverse health effects. Future research evaluating the impact of low-level exposure on livestock may clarify the potential impact on immunity. Trichothecenes are rapidly excreted from animals, and residues in edible tissues, milk, or eggs are likely negligible. In chronic exposures to trichothecenes, once the contaminated feed is removed and exposure stopped, animals generally have an excellent prognosis for recovery. This review shows the occurrence of trichothecenes in food and feed in 2011-2020 and their toxic effects and provides a summary of the discussions on the potential public health concerns specifically related to trichothecenes residues in foods associated with the exposure of farm animals to mycotoxin-contaminated feeds and impact to human health. Moreover, the article discusses the methods of their detection.

Exserohilum species are environmental molds that may rarely cause skin and nasal infections, especially in immunocompromised children. We present a 3-year-old girl with acute leukemia who presented with a skin infection caused by Exserohilum rostratum. Previously published cases of skin infections by Exserohilum spp. in children are reviewed.

We report a rare case of subcutaneous phaeohyphomycosis caused by Cladophialophora bantiana in an immunocompetent patient in Amazonas, Brazil. This dematiaceous fungus has been mainly associated with life-threatening infections affecting the central nervous systems of immunosuppressed patients. We present the clinical, laboratory, and therapeutic aspects, and in vitro susceptibility test results for different antifungal drugs. A brief review of the cases reported in the literature over the past 20 years has also been discussed. According to the literature review, the present case is the first report of subcutaneous phaeohyphomycosis due to C. bantiana in an immunocompetent patient in Latin America.

Aspergillus and Fusarium are the most common fungi causing mycotic keratitis. Injury to the eye with vegetable matter, cow tail injury, long-term use of topical steroids are some of the risk factors for mycotic keratitis. There are few case reports of keratitis caused by Bipolaris. The human pathogenic species in the genus are Bipolaris spicifera, Bipolaris hawaiiensis, Bipolaris papendorfii, and Bipolaris australiensis. Most commonly reported keratitis is caused by B. hawaiiensis, followed by B. spicifera. Literature review showed only one case report of keratitis due to B. australiensis reported from Australia. We present a first case report of keratitis due to B. australiensis (currently Curvularia australienis) from India.

The beta-lactam antibiotic cephalosporin C is produced industrially by Acremonium chrysogenum. Its derivative 7-aminocephalosporanic acid (7-ACA) is the intermediate of most chemical modification cephalosporins that are the most frequently used antibiotics for the therapy of infectious diseases. Due to its importance, the biosynthetic pathway of cephalosporin C has been elucidated in Acremonium chrysogenum. To improve the yield of cephalosporin C and reduce the cost of production, recent studies have been focused on the sophisticated regulation of cephalosporin C biosynthesis. In this review, recent advances in cephalosporin C biosynthesis and regulation are summarized.

Fusidic acid, an antibiotic produced from the Fusidium coccineum fungus, belongs to the class of steroids, but has no corticosteroid effects. It is indicated for the treatment of infections caused by methicillin-resistant Staphylococcus aureus strains. The aim of this study was to search for the properties of fusidic acid published so far in the literature, as well as the methods developed for its determination in biological samples and pharmaceutical formulations. From the findings, we can conclude that fusidic acid has been used for decades and is indicated for the treatment of serious infections caused by Gram-positive microorganisms to this day. Furthermore, it is a hypoallergenic agent, has low toxicity, shows low resistance, and has no cross-resistance with other clinically used antibiotics. The analytical method of high-performance liquid chromatography has been widely used for determining fusidic acid, since it can reduce the cost and time of analysis, making it more viable for routine quality control in the pharmaceutical industry.

Phaeohyphomycosis refers to infections caused by phaeoid fungi that can have an aggressive course in normal hosts. We report a case of left-sided renal phaeohyphomycosis due to Bipolaris spicifera in a 7-year-old immunocompetent male child. He presented with fever, dysuria, nausea, vomiting and flank pain. Examination revealed tenderness at the left costovertebral angle. Histological examination and culture of biopsy from left kidney and blood yielded the fungal pathogen Bipolaris spicifera. His past history revealed that he was diagnosed perinatally with bilateral hydronephrosis due to bilateral pelvic ureteric junction obstruction. He underwent an open dismembered pyeloplasty on the left side followed by the right side pyeloplasty at the age of 6 months and 1.5 years respectively. He was on a regular follow-up for 5 years and had been doing well. Now he was diagnosed as a case of unilateral renal phaeohyphomycosis. The patient was managed successfully with antifungal drugs amphotericin B and itraconazole. A review of previously reported bipolaris cases with their clinical manifestations, treatment and outcome is presented. Renal phaeohyphomycosis remains an unusual disease. Aggressive diagnostic approaches and careful management helped in survival of the patient.

Specific features in the development of micromycetes, typical mechanisms of their enzyme production, and conditions providing for an increase in enzyme secretion by the microscopic fungi in solid-state (on natural substrates and inert carriers) and membrane-surface liquid cultures are considered. The prospects and advantages of these fermentation methods for the production of extracellular enzymes are discussed and compared with submerged cultures.

The Fonsecaea species, which are the leading causes of chromoblastomycosis, are not considered neurotropic fungal agents. Fonsecaea pedrosoi is the primary species in the genus and is usually isolated from chromoblastomycosis cases. However, the recently distinguished species F. monophora has been reported in a few cerebral phaeohyphomycosis cases. Here, a case of cerebral phaeohyphomycosis caused by Fonsecaea monophora is presented in a 71-year-old female subject with chronic diabetes mellitus and hypertension. The identification of F. monophora was made through mycological and molecular analysis, and an isolate was differentiated from the closely related F. pedrosoi by sequence data on key bases on the ribosomal internal transcribed spacer region. The case was successfully treated with surgical and medical approaches, and the patient has remained healthy and stable after a ten-month follow up. Given the increasing incidence of this type of infection of the central nervous system (CNS), this case provides further support for the consideration that F. monophora might represent a neurotropic agent.