Typing

Typing of specific species of zygomycetes could be of importance in case of epidemics of human infections, but could also be of interest for epidemiological studies and in the field of food biotechnology or pharmaceutical industry for discrimination of isolates with particular enzymatic activity. Until now very few typing methods have been evaluated and none have been proven useful or sufficiently evaluated in the field of medical mycology. Intraspecies variability has been tested for clinical isolates of A. elegans by PCR-RFLP of ITS regions and by microsatellite markers (Chakrabarti et al., 2003) but PCR-RFLP failed to discriminate between isolates and microsatellite typing was not discriminatory enough. Recently, typing of 20 zygomycete isolates, in a single institution, by a PCR technique based on the amplification of repetitive genomic sequences showed different typing patterns suggesting the lack of clonality and then the absence of a common source of contamination (Kontoyiannis et al., 2005). In one case report of a patient with a hepatic zygomycosis after ingestion of naturo-pathic medicines (Oliver et al., 1996), the same species, M. indicus, was isolated from the patient's liver abscess and from the pills of the naturopathic medicine. Arbitrary-primed PCR analysis suggested that both isolates were genetically identical.

More extensive data have been obtained for R. oryzae isolates for biotechnology purposes. Sequencing of the ITS regions of 64 strains of R. oryzae showed that some polymorphism was present (Abe et al., 2003). This polymorphism was not important enough for typing purposes but allowed to cluster the isolates in two distinct groups. Interestingly, there was a correlation between ITS type and production of lactic acid by the strain. These results allowed the design of specific primers for molecular detection of strains that produce lactic acid (Abe et al., 2003). The low variability of ITS sequences of R. oryzae has also been reported recently for clinical isolates (Schwarz et al., 2006) suggesting that ITS sequencing is not discriminatory enough for epidemiological purposes. More genetic variability has been observed by sequencing the lactate dehydrogenase genes from a large panel of R. oryzae isolates (Saito et al., 2004) but this approach has not been tested in clinical isolates.

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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