Although medical mycology is recognized by its practitioners as an independent area of professional commitment, its roots can be traced to a broad range of medical and biological disciplines. It incorporates elements from such diverse fields as dermatology, genetics, pathology and histopathology, infectious disease, veterinary medicine, mycology, immunology, microbiology, epidemiology, and more recently, cellular and molecular biology. It follows that the term “medical mycologist” is an imprecise one, and does not adequately indicate origins and spheres of interest of those who work in the field.
Medical mycology is perhaps best viewed as a mosaic rather than an amalgam, the cement which binds its component parts together being mycology itself. It is an interest in the fungi, their products and their activities which constitutes the single unifying element that links medical mycologists and their endeavours throughout the world.
In this presentation, I wish to concentrate on medical mycology as it is today. The history of its development is of equal relevance to an understanding of the subject is the history of its development, but I propose to explore this topic more fully in my Presidential Address at the 11th ISHAM Congress in Montreal next year.

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Nine strains of Arxula, Stephanoascus, Endomyces, Yarrowia, Dipodascus, and Geot richum were examined regarding the partial sequences of 18S and 26S rRNAs. In the positions 471 through 627 of 26S rRNA, the two strains examined of the genera Arxula and Stephanoascus had 99% and 98% maximum homologies, respectively. The two species of the genus Arxula, A. terrestris and A. adeninivorans had 80% maximum homology. The maximum homologies were 81-84% between the genera Arxula and Stephanoascus. Arxula, Endomyces, Yarrowia, Dipodascus, Geotrichum, and Saccharomyces species constituted their own separate clusters at 49-76% maximum homologies. In the positions 1685 through 1835 of 26S rRNA, the two strains examined of the genera Arxula and Stephanoascus had 2 and 0 base difference, respectively. The two species of the genus Arxula had 7-9 base differences. The base differences were 4-8 between the genera Arxula and Stephanoascus. Arxula, Endomyces, Yarrowia, Dipodascus, Geotrichum, and Saccharomyces species constituted their own separate clusters at 13-25 base differences. In the positions 1451 through 1618 of 18S rRNA, the two strains examined of the genera Arxula and Stephanoascus had no base difference, respectively. The two species of the genus Arxula had 2 base differences. The base differences were 2-4 between the genera Arxula and Stephanoascus. Arxula, Endomyces, Yarrowia, Dipodascus, Geotrichum, and Saccharomyces species constituted their own separate clusters at 5-9 base differences. The data obtained are discussed from the taxonomic and phylogenetic points of view.

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Basidiosporogenous yeasts and basidiomycetous anamorphic yeasts have been classified based on the morphological, physiological and biochemical characteristics. Higher taxonomic ranks such as genus, family etc. are classified based on the mode of vegetative reproduction, morphological characteristics found during sexual reproduction and certain physiological characteristics such as the assimilability of inositol. Recent chemosystematics studies suggest the unreasonableness of the taxonomic system based on these characteristics. Monosaccharide compositions of the cells, especially the presence or absence of xylose, and ubiquinone systems are suggested to be more reliable systematic criteria than the mode of vegetative reproduction and morphological criteria found during the sexual reproduction on the basis of the partial sequencing study of rRNAs. Ultrastructural features well correlate with chemosystematics characteristics and are regarded as reliable systematic criteria in higher taxonomic ranks. Polyphasic approaches are essential for further progress of the systematics of basidiomycetous yeasts.

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Penicillium is a taxonomically difficult genus of great importance in fields as diverse as food spoilage, biotechnology, biodeterioration, plant pathology and medicine. Traditional morphological approaches to taxonomy have been less than satisfactory, so in recent years a wide range of newer techniques-chemical, biochemical and physiologicalhave been applied. Taking a broad view of chemotaxonomy in this paper, the most successful of these approaches will be discussed. Valuable physiological tests have been measurements of colony diameters after growth under particular temperature or water activity conditions, or on selective substrates. The most useful new biochemical tools have been electrophoretic patterns of isoenzymes, of great value in subgenus Penicillium, and electrophoretic patterns of DNA and RNA after cleavage with specific nucleases. Chemical tests of most value include the use of ubiquinone systems as a broad measure of relatedness among groups of species, and secondary metabolite profiles, most useful at species and subspecies levels. Penicillium taxonomy is currently moving towards stability and consensus through international cooperation, involving the integration of all of these techniques. The newly established International Commission on Penicillium and Aspergillus will increasingly provide guidance in this direction.

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The complexity of Aspergillus has been emphasized by the diversity of teleomorph and the heterogeneity of ubiquinone systems. The resolution by traditional morphological approaches has been limited, and a need for newer approaches has become apparent. Current trends in Aspergillus chemotaxonomy are presented based mainly on our previously published and unpublished data on electrophoretic comparisons of enzymes and their numerical analyses, ubiquinone systems, and partial sequences of 18S ribosomal RNA. Combinations of such chemotaxonomic indicators including nuclear DNA base composition and DNA-DNA homology support or bring into question taxonomic decisions in recent years based primarily on the morphological species concepts in Aspergillus and associated teleomorph, while further comparisons of 18S ribosomal RNA partial sequences can shed light on the phylogenetic and evolutionary background of both.

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The wall and outer surface of pathogenic fungi is involved in adhesion and cell shape maintenance, and acts as a barrier to metabolites and drugs. In addition the cell wall contains immunogenic determinants, immunomodulators and secreted enzymes. The cell wall of C. albicans comprises some 30% of the dry weight of the cell and is composed predominantly of mannoproteins and β-glucans with small quantities of chitin, protein and lipid. Transmission electronmicroscopy of the wall reveals a number of different layers; the thickness and number of these layers varies during germ-tube formation and the cell cycle. The outer fuzzy layer of the wall contains receptors that bind plastic, laminin, fibrinogen, and C3 fragments of complement. The β1, 3 and β1, 6 glucans and chitin are the polymers which endow rigidity on the cell wall. These polymers form a microfibrillar scaffolding upon which other macromolecules, particularly mannoproteins are bound.
The wall mannoproteins are highly branched polysaccharides primarily composed of mannose units attached to protein through a G 1 cNac dimer bridge and asparagine. There are also smaller numbers of 0-linked mannoproteins where the mannose units are attached to protein through serine and threonine residues. The mannoproteins have a backbone of α-1, 6 linked mannose units to which side chains of mannoses attach via α-1, 2-and occasionally α-1, 3 bonds. The side chains are the major antigenic determinants and the A and B serotypes are distinguished by differences between these side chains. A model for cell wall growth and development will is described.

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The involvement of cell wall glucans in the process of dimorphism in Paracoccidioides brasiliensis has been proposed for many years. The control of glucan synthetase activity through cytoplasmic factors is also considered. Current research on biochemical aspects of dimorphism in P. brasiliensis suggests that proteinases are involved in the control of β-glucan synthetase activity in the generation of the fungal cell wall. The probable involvement of protein disulfide reductase is also suggested. A complementary model of yeast mycelium transformation is proposed.

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We defined optimal conditions for detection of cryptococcal antigen using latex particles sensitized with anti-C. neoformans globulin fractionated by 40 % saturated ammonium sulfate. Latex particles, with a diameter of 0.81 μm, were sensitized with 20 μg of anti-C. neoformans globulin per mg latex. The agglutination test was performed using a mixture of 75 μl of protease treated serum or cerebrospinal fluid (CSF) and 25 μl of sensitized latex suspension. After 10 minutes reaction on a rotator, the agglutination was read. We compared the minimal concentration of polysaccharide antigen detectable with our materials and procedure and with commercially available kits and obtained almost the same sensitivities. However, our procedure was also capable of detecting antigen in soluble immune complexes in patient's serum. The sensitivity of our latex agglutination test using the sensitized latex particles was found to be 100% in cases of cryptococcal meningitis, 81.8% in pulmonary cryptococcosis and 75 % in cutaneous cryptococcosis. The specificity of our test was 100% with sera and 95% with CSF. We concluded that commercial kit B was the more useful because of its protease pre-treatment which reduced the problems of false positives due to rheumatoid factor and false negatives due to soluble immune complexes.

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Host defenses substances against fungi and other microorganisms are discussed by classifying them into four categories, and especially the paper dealt with the significants of cationic polypeptide system among the four because this is ubiquitous in the variety of tissues.
1. Oxidative system
2. Enzymatic system
3. Chelating system
4. Cationic system
These defense substances affect the efficacy of topical antimycotics because the MIC of the defense substances are as potent as antimycotics of the present usage.

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Increasingly high incidence of deep-seated mycosis in immunocompromised patients with underlying diseases such as hematopoietic malignancies, solid tumors, organ transplants and AIDS has presented serious problems in recent years in Japan due to difficulties in treatment and high mortality.
At present, only 4 antifungal agents are available to treat these disease in Japan; amphotericin B, flucytosine, miconazole and fluconazole.
But the treatment of deep-seated mycosis is limited due to difficulties of early diagnosis and side effects by amphotericin B.
The antifungal agents and recent advance in chemotherapy for deep-seated mycosis are reviewed from the literature on the following points; antifungal agents at present and in future, improvement and dosage form modification of existing antifungal agents, new attempts for reducing adverse events and new informations about the adverse events and the interactions of antifungal agents. Besides antifungal agents, adjuvant therapies with immunomodifiers (BRM) and cytokines play an important role in the treatment of mycosis, but I narrowed down the focus to only antifungal agents in this paper.

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New advances have been made in the serodiagnosis and chemotherapy of fungal diseases and interest in these subjects is currently at peak level. However, the escalating incidence of opportunistic fungal infections, in patients who are debilitated, receiving immunosuppressive therapy, and those who are being treated aggressively for other dis-eases, dictate that improved procedures be developed for the rapid presumptive serologic diagnosis of these diseases along with better antifungal strategies to manage them. This need will continue to increase as a result of the growing number of individuals who are becoming afflicted with the human immunodeficiency virus (AIDS).
Traditional serologic procedures based on detection of antibody are frequently misleading as a result of the changing patterns of disease in the susceptible population and tests that detect antigen have been helpful in identifying some cases, but problems still exist. The technic of DNA hybridization and polymerase chain reaction provide newer approaches worthy of exploitation.
In parallel with the growing incidence of life-threatening fungal infections and efforts to devise tests that rapidly diagnose and monitor them has been the need for and development of new antifungal agents, elucidation of their mechanisms of action, and novel strategies for their delivery. While many improvements have been made there is still problems with toxicity, specificity of action, and efficacy. Research focused on detailing the molecular biology of fungal pathogens provides an alternative strategy for drug development.

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