This report describes the application of PCR fingerprinting for the identification of species and varieties of common dermatophytes and related fungi utilizing as a single primer the simple repetitive oligonucleotide (GACA) 4 . The primer was able to amplify all the strains, producing species-specific profiles for Microsporum canis, Microsporum gypseum, Trichophyton rubrum, Trichophyton ajelloi, and Epidermophyton floccosum. Intraspecific variability was not observed for these species. Instead, three different profiles were observed in the Trichophyton mentagrophytes group.Routine procedures for dermatophyte species identification rely on examination of the colony (pigmentation of the surface and reverse sides, topography, texture, and rate of growth) and microscopic morphology (size and shape of macroconidia and microconidia, spirals, nodular organs, and pectinate branches). Further identification characteristics include nutritional requirements (vitamins and amino acids) and temperature tolerance, as well as urease production, alkaline production of bromocresol purple medium, in vitro hair perforation, etc. (9, 16). Morphological and physiological characteristics can frequently vary; in fact, the phenotypic features can be easily influenced by outside factors such as temperature variation, medium, and chemotherapy (11) and therefore strain identification is often difficult.In the last few years genotypic approaches have proven to be useful for solving taxonomic problems regarding dermatophytes; in fact, genotypic differences are considered more stable and more precise than phenotypic characteristics (2, 11).Molecular methods, such as restriction fragment length polymorphism analysis of mitochondrial DNA (1,7,8) , have brought important progress in distinguishing between species and strains. However, most of these techniques (e.g., restriction fragment length polymorphism analysis, sequencing) are complex, laborious, time-consuming, and not easily employable for routine identification of dermatophytes; in contrast, PCR technology is simple, rapid, and, in the absence of specific nucleotide sequence information for the many dermatophyte species, able to generate species-specific or strain-specific DNA polymorphisms on the basis of characteristic band patterns detected by agarose gel electrophoresis (2, 11).This report describes the application of PCR fingerprinting for the identification of species and varieties of common dermatophytes and related fungi utilizing as a single primer the simple repetitive oligonucleotide (GACA) 4 previously used by Meyer and others to distinguish strains of Cryptococcus neoformans (12, 13) and species of the genus Candida (14 Furthermore, the study was conducted on various strains both from collections and from clinical isolation with the aim of finding the presence of an intraspecific variability.Strains. Out of a total of 140 strains selected for the study, 29 were obtained from the collection of the Institut Pasteur of Paris, France. One hundred eleven clinical isolates were re...

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The authors present a worldwide review of isolations of Cryptococcus neoformans, var. neoformans and C. neoformans var. gattii from animals and vegetation, referring in particular to the already well-known association of the former variety with Eucalyptus camaldulensis. They then review the Italian situation relative to this association and their studies carried out in Central Italy: in Latina (Lazio), Pisa, Viareggio and Lake Massaciuccoli (Tuscany). From the 256 E. camaldulensis trees examined C. neoformans var. gattii was not isolated. An E. camaldulensis tree situated in the nature reserve on Lake Massaciuccoli proved to be positive for C. neoformans var. neoformans. This variety was isolated from the leaves, flowers, bark and the debris at the foot of the tree, suggesting that it had colonized the entire tree and that it was capable of developing not only on its usual habitat (bird guano, soil rich with guano) but also on Eucalyptus trees. The identity of the isolates was confirmed by their genomic profiles obtained by random amplification polymorphic DNA (RAPD) with the primer (GACA)4. The presence of a single genotype indicates a sole source of contamination, perhaps brought by a bird coming from a contaminated environment.

SummaryAuthors compare two methods of extracting DNA from different fungi: the classic method with phenol/chloroform (P/C) and that with magnetic beads. Both were tested on Candida albicans and Cryptococcus neoformans var. neoformans, belonging to the yeast group and Microsporum canis, M. gypseum, Trichophyton rubrum, T. interdigitale, T. ajelloi, Epidermophyton floccosum, belonging to the dermatophytes group. Extraction products underwent polymerase chain reaction (PCR) fingerprinting with the appropriate primers to point out any disagreement in the genomic profiles. After having determined that the genomic profiles obtained from the DNA extracted from the same strain with the two methods correspond perfectly, the authors concluded that the extraction method with magnetic beads from fungal cells is simpler and quicker than with P/C extraction, greatly facilitating the obtainment of fungal DNA.

SummaryTo determine whether canine faecal contamination may represent a source of environmental contamination with Toxocara canis eggs within the urban area of Florence, a total number of 754 dog faeces were collected in 7 public places and examined by routine floatation technique during one-year period. The total prevalence of intestinal nematode eggs was 8.6 %. Trichuris vulpis (4.6 %) eggs were the most prevalent followed by T. canis (3.6 %) and Ancylostomidae (1.7 %) eggs. Mixed infections included T. canis/T. vulpis (0.7 %), Ancylostomidae/T. canis (0.4 %), and Ancylostomidae/T. vulpis (0.3 %). Total prevalence of intestinal nematode eggs was significantly higher in spring than in winter (OR = 2.06). Our results indicate a low prevalence of T. canis eggs suggesting that dog faeces left on soil are unlikely to cause high environmental contamination with T. canis eggs in the town of Florence.