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The Fungi
Published in Julius P. Kreier, Infection, Resistance, and Immunity, 2022
Cutaneous infection involving the skin, hair, and nails is the most common manifestation of disease caused by the dermatophytes, which belong to the genera Mi-crosporum, Trichophyton and Epidermophyton. These fungi are unique because they are able to utilize keratin as a source of energy The dermatophytes have been grouped according to their more natural environmental habitat. Geophilic dermatophytes such as Microsporum gypseum are able to survive in the soil for extended periods of time and retain their infectivity. Zoophilic dermatophytes such as Microsporum canis have become dependent on animal hosts which then serve as sources of dissemination. These agents have limited capacity to survive in the environment. The anthropophilic agents such as Trichophyton mentagrophytes have become dependent on humans. Although most of these agents do have a preferred host, cross-species infections can occur and in unusual hosts can result in diseases of greater severity but of shorter duration.
Fenugreek in Management of Immunological, Infectious, and Malignant Disorders
Published in Dilip Ghosh, Prasad Thakurdesai, Fenugreek, 2022
Rohini Pujari, Prasad Thakurdesai
The initial evidence shows antifungal effects of aqueous extracts of various plant parts of fenugreek (3%) and methanolic fractions of the aerial parts against pathogenic mycelial fungi (Haouala et al. 2008). In this study, Rhizoctinia solani, Fusarium graminearum, and Alternaria sp. were the most sensitive species, and Pythium aphanidermatum was most resistant to fenugreek (Haouala et al. 2008). Subsequently, the antifungal activity of methanolic extracts of fenugreek seeds (against Aspergillus flavus, Trichophyton rubrum, and Candida albicans) (Alluri and Majumdar 2014) and leaves (against Trichoderma viridae) was reported (Dharajiya et al. 2016). Furthermore, ethyl acetate extract of fenugreek leaves (6.25 mg/ml) also showed potent antifungal properties against T. viridae (Dharajiya et al. 2016). Recently, the petroleum ether, aqueous, ethyl acetate, and ethanol extracts of fenugreek seed powder reported potent antifungal activity at 25, 50, and 100 μml against Microsporum gypseum (Sudan, Goswami, and Singh 2020). In addition, a defensin-like antifungal peptide (Tf-AFP) isolated from fenugreek seed, was reported to inhibit the growth of fungal species such as Rhizoctonia solani, Fusarium solani, and Fusarium oxysporum during in vitro testing (Oddepally and Guruprasad 2015).
Skin infections
Published in Rashmi Sarkar, Anupam Das, Sumit Sethi, Concise Dermatology, 2021
Shankila Mittal, Rashmi Sarkar
The species causing dermatophytic infection can be classified as:Anthropophilic – e.g., Epidermophyton floccosum, Trichophyton mentagrophytes var. Interdigitale, Trichophyton rubrum, Trichophyton schoenleinii, Trichophyton soudanense, Trichophyton tonsurans, Trichophyton violaceum, etc.Zoophilic – Microsporum canis (dogs, cats), T. verrucosum (cattle) and T. equinum (horses).Geophilic – Microsporum gypseum, Microsporum praecox
The role of mTOR in age-related diseases
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2021
Zofia Chrienova, Eugenie Nepovimova, Kamil Kuca
Collecting soil samples on Easter Island (Rapa Nui) in the 1970s, no one could predict that bacterial cultures of Streptomyces hygroscopicus isolated from these samples would change the way we look at the cell cycle and help us better understand several signalling pathways and cellular processes. The isolated strain demonstrated inhibitory effects on Candida albicans, Microsporum gypseum, Trichophyton granulosum, as well as other gram-positive bacteria, while all gram-negative species were resistant. It was soon shown that S. hygroscopicus produces an antibiotic with antifungal properties, named rapamycin after its place of discovery (Figure 1). This substance, also known by its generic name sirolimus, is a lipophilic macrolide with a white crystalline structure that is insoluble in water but readily soluble in organic solvents1–3.
The association of isoconazole–diflucortolone in the treatment of pediatric tinea corporis
Published in Journal of Dermatological Treatment, 2018
Stefano Veraldi, Rossana Schianchi, Paolo Pontini, Alberto Gorani
Tinea corporis is a common mycotic infection in children. Transmission is due to contacts with animals, humans, and soil. Microsporum canis, Trichophyton rubrum, Trichophyton mentagrophytes, and Microsporum gypseum are the species more frequently involved. Latency time ranges from one to three weeks. The face and upper limbs are usually involved. Tinea corporis presents with a single round or oval erythematous lesion, with scales in the center and well defined, vescicular borders. Pruritus is usually mild to moderate (1). Staphylococcus aureus superinfections may be observed in atopic children suffering from severe pruritus and consequent scratching. We present the results of a sponsor-free study about the use of the topical association isoconazole–diflucortolone in children with tinea corporis.
Immunosuppression in the Management of Presumed Non-infective Uveitis; Are We Sure What We are Treating? Notes on the Antimicrobial Properties of the Systemic Immunosuppressants
Published in Ocular Immunology and Inflammation, 2020
In 1972 a new macrolide compound was isolated from a sample of Streptomyces hygroscopicus bacteria found on Rapa-nui (Easter Island) and therefore named rapamycin. Initially investigated as an antifungal, it was found to be active against Candida albicans, Microsporum gypseum, and Trichophyton granulosum.61 Subsequently, it was found to have powerful suppressive action against a phosphatidylinositol-3 protein kinase essential for cellular metabolism, subsequently named “mammalian target of rapamycin” (mTOR), and it inhibits T-cell activation and IL-2 receptor signaling. It was therefore developed as an immunosuppressive and renamed sirolimus. Although structurally similar to tacrolimus, it has no calcineurin antagonistic activity. Nevertheless, further antimicrobial properties were discovered: antifungal activity against Saccharomyces cerevisiae and Aspergillus niger was identified, and although the bacteria Escherischia coli, Proteus vulgaris, Pseudomonas aeruginosa and various Bacillus spp. were unaffected, sporulation of Bacillus brevis Nagano was inhibited, an unexplained specific antibacterial effect.62 No other antibacterial effects have been found. Further in vitro studies identified strong activity against the mold Fusarium oxysporum but commented that antifungal activity shown in liquid media could differ substantially from that exhibited on agar plates.63 More recently, significant activity against Mucor circinelloides demonstrated a potential alternative antifungal in devastating mucormycosis or potentially, other zygomycoses.64