A short review on the onychomycoses by dermatophytes in Romania

In 525 patients with onychomycoses by dermatophytes, collected in Bucharest (45% of the cases being females), the toe-nails were found to be affected in 65% of the cases, while the finger-nails only in 20%. In order of frequency, the following agents were isolated:T. rubrum (55%),T. mentagrophytes (interdigitale — 26%),T. violaceum (12%),E. floccosum (3%),T. schonleinii (1.3%). Only sporadically were found other species, viz.:M. canis (4),T. tonsurans (3),T. verruccosum (2),T. quinckeanum (1) andM. audouinii (1). Tinea pedis was the main manifestation associated with the respective cases.     

High-performance liquid chromatographic identification of beta-lactam antibiotics produced by dermatophytes

Thirteen of 48 dermatophyte isolates were found by bioassay to produce beta-lactam antibiotics and seven produced other antibiotics. Estimation and detection of specific beta-lactams in culture broths by derivatization and HPLC was only possible following concentration and extraction procedures. Analysis of the concentrated broths demonstrated the production of penicillin X and penicillin G by two Trichophyton mentagrophytes strains and by one Microsporum canis strain; one further T. mentagrophytes strain produced only penicillin X. Additions of the beta-lactam side-chain precursors, phenylacetic acid and phenoxyacetic acid, to fermentation media failed to increase the antibiotic titres.     

High-performance liquid chromatographic identification of beta-lactam antibiotics produced by dermatophytes

Thirteen of 48 dermatophyte isolates were found by bioassay to produce beta-lactam antibiotics and seven produced other antibiotics. Estimation and detection of specific beta-lactams in culture broths by derivatization and HPLC was only possible following concentration and extraction procedures. Analysis of the concentrated broths demonstrated the production of penicillin X and penicillin G by two Trichophyton mentagrophytes strains and by one Microsporum canis strain; one further T. mentagrophytes strain produced only penicillin X. Additions of the beta-lactam side-chain precursors, phenylacetic acid and phenoxyacetic acid, to fermentation media failed to increase the antibiotic titres.     

Use of arbitrarily primed polymerase chain reaction to differentiate Trichophyton dermatophytes

Abstract Dermatophytes such as Trichophyton species are common human pathogens, the infection of which results in dermatophytosis (also known as ringworm). Several laboratory tests are used routinely for the diagnosis of dermatophytosis, but they are either slow or lacking specificity. Through examination of genomic DNA from Trichophyton dermatophytes and other fungi in arbitrarily primed PCR, it was shown that a random primer 5'-ACCCGACCTG-3' produced bands of 4.3 kb, 1.9 kb, 1.7 kb and 0.7 kb in T. rubrum DNA, bands of 2.5 kb, 1.9 kb and 0.8 kb in T. mentagrophytes var. interdigitale and T. mentagrophytes var. mentagrophytes DNA, and bands of 2.5 kb, 1.9 kb, 1.5 kb and 0.9 kb in T. tonsurans DNA. This primer amplified bands of different sizes in other fungal DNA. Therefore, based on the distinct band patterns observed in arbitrarily primed PCR using this primer, T. rubrum , T. mentagrophytes and T. tonsurans dermatophytes could be rapidly differentiated.     

Influence of Griseofulvin treatment on semen quality in the dog

Griseofulvin is used to treat dermatomycosis in many species and causes oligospermia in supra-pharmacological doses. The aim of the present study was to evaluate the effect of Griseofulvin administered at therapeutic doses upon semen quality in dogs. Four dogs were treated with Griseofulvin (25 mg/kg per day) for 30 days. Semen collections and analyses were performed before, during and for 100 days after treatment for the Griseofulvin group and 10 untreated control dogs. Semen analyses included mean percentage of forward progressively motile sperm, total sperm output, normal live sperm and normal dead sperm. There was no significant difference between control and treated dogs for each of the semen quality parameters. Therapeutic dosage of Griseofulvin had no deleterious effect upon semen quality in dogs, although this does not preclude potential embryotoxic and teratogenic effects.     

In vitro susceptibility of dermatomycoses agents to six antifungal drugs and evaluation by fractional inhibitory concentration index of combined effects of amorolfine and itraconazole in dermatophytes

To investigate the antifungal drug susceptibility of fungi responsible for dermatomycoses, minimum inhibition concentration (MIC) tests were performed in 44 strains of dermatophytes, including Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton verrucosum, Trichophyton tonsurans, Microsporum canis, Microsporum gypseum and Epidermophyton floccosum, with six antifungal drugs (amorolfine, terbinafine, butenafine, ketoconazole, itraconazole and bifonazole) by broth microdilution assay according to Clinical Laboratory Standard Institute protocols. Six possible dermatomycosis‐causing non‐dermatophytic fungi were also tested. The two major causes of tinea, T. rubrum and T. mentagrophytes, showed significantly different sensitivities to ketoconazole and bifonazole. Clinically derived dermatophytes were sensitive to the six antifungal drugs tested. However, non‐dermatophytes, especially Fusarium spp., tended to be resistant to these antifungal drugs. In Trichophyton spp., the MICs of non‐azole drugs had narrower distributions than those of azoles. To evaluate the effects of antifungal drug combinations, the fractional inhibitory concentration index was calculated for the combination of amorolfine and itraconazole as representative external and internal drugs for dermatophytes. It was found that this combination had synergistic or additive effects on most dermatophytes, and had no antagonistic effects. The variation in susceptibility of clinically derived fungal isolates indicates that identification of causative fungi is indispensable for appropriately choosing effective antifungal drugs in the early stages of infection. The results of combination assay suggest that multiple drugs with different antifungal mechanisms against growth of dermatophytes should be used to treat refractory dermatomycoses, especially onychomycosis.     

Revisiting the epidemiology of onychomycoses

Onychomycoses represent a group of nail affections caused by one or more fungi. Whether aging represents a risk factor for developing onychomycosis, remains a question. In the present work, we studied the variations in frequency and prevalence of onychomycoses and non-mycotic onychodystrophies according to age. Our results show that there is an increase in the frequency and prevalence of onychomycoses and non-mycotic onychodystrophies predominantly in patients over forty years of age.     

Comprehensive analysis of proteins secreted by Trichophyton rubrum and Trichophyton violaceum under in vitro conditions

Dermatophytes cause most superficial mycoses in humans and animals. Their pathogenicity is probably linked with the secretion of proteins degrading keratinised structures. Using 2D-PAGE and a shotgun mass spectrometry approach, we identified 80 proteins from Trichophyton rubrum and Trichophyton violaceum secretomes, under conditions mimicking those in the host. Identified proteins included endo- and exoproteases, other hydrolases, and oxidoreductases. Our findings can contribute to a better understanding of the virulence mechanisms of the two species and the different types of infection they cause.     

Pigment formation in the dermatophytes

Avstract The moist mycelium ofT. tonsurans was extracted with 3 % w/v sodium hydroxide to yield a purple to violet solution which was passed through a cation-exchange resin column, evaporated partially, dialyzed and lyophilized. The lyophilized powder was extracted using absolute ethanol, acetone and chloroform (Process A) and separately by defatting with petroleum ether and n-hexane followed by chloroform-methanol 2:1 (Process B).Separation was achieved for the extract of Process B on thin layer chromatography using Silica Gel G and butanol-ethanol-water as the solvent system. Ultra-violet and visible spectrophotometric absorption data are reported for the lyophilized extract ofT. tonsurans, hydrolyzates of the lyophilized extract, and for sodium hydroxide extracts ofT. megnini, T. mentagrophytes, T. rubrum, T. tonsurans andT. violaceum. The spectra were similar in all cases.A review of pigment substance in dermatophytes is made, which together with the experimental data secured withT. tonsurans and previous experimentation, suggest the possible effects of drying procedures, contusion, solvents, acidic additives and method of extraction on the removal of pigment from the mycelium of dermatophytes. It is suggested that all the above conditions influence the substances ultimately extracted and that some alteration of a basic pigment association in the organism occurs to release pigment fragments or fractions of varying complexity. Oxidation and polymerization may influence the end result. It is possible that the mechanism presented can account for the number of pigment substances reportedly occurring in the dermatophytes and that a similar pigment structure or complex exists in other Trichophyton species.Grateful thanks are extended to the Medical Research Council of Canada for financial support.     

Some remarks on the clinical characteristics,infectiousness and treatment of dermatycoses caused by Trichophyton rubrum

The object of this report was to draw the attention of the dermatological public to the present-day variability of the clinical pictures produced byTrichophyton rubrum and to new findings which help to explain some of the more severe forms. Its purpose is also to remind the reader that local therapy, which has unwarrantedly been underestimated by some dermatologists since the discovery of griseofulvin, still has a significant place in treatment.