Alterations in phospholipid and fatty acid composition of Candida albicans were examined during yeast cell (Y) to mycelial cell (M) transformation. The major phospholipids were phosphatidylcholine, phosphatidylethanolamine and phosphatidylserine/phosphatidylinositol. A large decrement of phosphatidylserine/phosphatidylinositol and a great increase of linoleic acid in all phospholipids were found to occur within 3 to 5h after the emergence of the conversion.
A comparative lipid analysis of plasma membranes isolated from the two cell forms showed that sterol content of the M-form cells was approximately three times greater than that of the Y-form. ESR spectra data revealed the less fluid physical state of the M-form plasma membrane.
The activity of chitin synthetase (EC: 2.4.1.16) which is associated with plasma membranes was several times higher in the M-form than in the Y-form. The phospholipases (EC: 3.1.1.5.32) were found to be secreted into the medium by Y-form cells with growth age. These results suggest that modification of membrane lipid composition might play a role in the transformation of dimorphic morphogenesis of Candida albicans.

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Sporothrix schenckii cells were incubated in antisera against S. schenckii, Cladosporium werneckii and Saccharomyces cerevisiae followed by treatment with a ferritin conjugated anti-rabbit IgG serum (goat). S. schenckii cells were also treated with a ferritin conjugated concanavalin A or cationized ferritin. The study of ferritin particles on the cell surface using a scanning electron microscopy proved that serological determinants of rhamnose and galactose, but not mammose, and acidic amino acids were localized at the cell surface of S. schenckii.

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To produce an animal model for the study of fungal keratitis, a new procedure was investigated. Using white rabbits bred and raised at Tokyo Medical and Dental University and a new inoculation technique, a highly reliable and reproducible system suitable for the evaluation of antifungal drugs and study of the pathogenicity of various fungi was developed.
Using this animal model, the pathogenicity of Fusarium solani, F. moniliforme, F. oxysporum, F. equiseti, F. culumorum and Candida albicans for rabbit cornea was investigated and various factors related to fungal keratitis were studied.

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The neurotropism of the pathogenic dematiaceous fungi Fonsecaea pedrosoi, Cladosporium trichoides, Exophiala dermatitidis, Exophiala jeanselmei and Phialophora verrucosa was investigated using congenitally athymic nude (nu/nu) mice and their heterozygous (nu/+) littermates.
The first three species severely affected the brains of both mouse's strains while the latter two did not.
In the brains of both groups infected with F. pedrosoi, microabscesses with short hyphae appeared at an early stage of infection. Thereafter, in the nu/+ mice purulent lesions changed to granulomatous ones about 10 days after inoculation and hyphae were destroyed in the granulomas. In the nu/nu mice hyphae continued to grow and formed large purulent and necrotic lesions.
In the brains of the nu/+ and nu/nu mice inoculated with C. trichoides, microabscesses with slender hyphae appeared at an early stage of infection. As infection advanced, large purulent and necrotic lesions with abundant septated hyphae were formed in the nu/+ mice, while in the nu/nu mice slender septated hyphae grew freely without cellular responses.
In the E. dermatitidis infection microgranulomas with yeast-like cells were formed from day 4 on in the brains of both groups of mice. Even though the foci disappeared gradually by the 40th day in the nu/+ mice, a considerable number of them was counted in the nu/nu mice until the end of the experiment (62 days). Interestingly, acid mucopolysaccharide was stained around the yeast-like cells in the microgranulomas with alcian blue.

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The experimental injection of Aspergillus fumigatus in mice was examined by intravenous inoculation at doses of 5×10⁶ and 10⁷ viable spores. The viable organisms were detected in the kidney and brain ten days after challenge and secretion of Asp-hemolysin from the mycelia was actually observed immunohistochemically in the tissues using a technique of indirect enzyme labeled antibody (peroxidase binding IgG antibody).
With the simultaneous administration of Asp-hemolysin and the organism, the toxin was shown to be a virulent factor in A. fumigatus infection. On the other hand, pretreatment with antitoxin IgG-antibody exhibited greater protective effect against A. fumigatus invasion than did IgM antibody.
In histopathological aspects, lesions of various degrees were observed in the kidney, heart, liver and brain of mice injected with the hemolytic toxin from A. fumigatus. The toxin was definitely bound to arterial walls in the kidney and brain. Intraperitoneal injection caused an increase in capillary permeability, and the toxin showed higher cytotoxicity to human leukocytes and guinea pig alveolar macrophages in vitro.

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A methodology to detect the yeast antigen in the serum of mice infected with C. albicans was devised by applying a radioimmunoassay using ¹²⁵I-labeled C. albicans glycoprotein toxin. A relatively high concentration, 100-1, 000ng/ml, of the antigen was detected in the serum of mice which had received an intravenous injection of a minimum lethal dose (MLD) of the yeast cells. The duration of antigen release was relatively long, ranging from the early to late stages of the infection. When mice were inoculated intravenously with 1/10 MLD of the yeast, the antigen was not demonstrable, whereas animals pretreated with cortisone showed an antigen concentration as high as those challenged with the larger inoculum. The cortisone-treated animals also developed a more vigorous multiplication of inoculated organisms than the non-treated ones. These results suggest that the determination of Candida antigen in the serum might allow diagnosis of deep-seated Candida infection.

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A comparison of proteins isolated from yeast and mycelial form cells of Sporothrix schenckii was made using SDS slab gel electrophoresis. A unique band (M. W.=150, 000) was identified from yeast form cells. Amino acid analysis revealed that this protein contained mainly glycine, glutamic acid, serine and alanine. Several specific bands were also identified from the culture media of mycelial and yeast forms. The relation of these proteins to the dimorphism of S. schenckii was discussed.

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Biochemical alterations were examined in mice intravenously challenged with either Asp-hemolysin or A. fumigatus viable spores. It was observed that the serum levels of non-protein nitrogen and blood urea nitrogen were elevated in mice challenged with Asp-hemolysin. Serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase and lactic dehydrogenase activities were also greatly elevated. The challenge with A. fumigatus viable spores also resulted in a significant change in serum constituent concentration. The alterations supported the lesions of organs in histopathologic aspects observed previously, indicating that tissue damage by Asp-hemolysin may be responsible for the establishment and development of A. fumigatus infection.

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The influence of high concentrations of NaCl, KCl and MgCl₂ on the growth and conidiogenesis was examined on some strains of dermatophytes, namely Microsporum audouinii, M. langeronii and Arthroderma vanbreuseghemii. The salts examined were incorporated by serial concentrations ranging from 0.5 to 8.0% or more into the basal medium composed of peptone, dextrose and agar. The effects of high concentrations of all these salts on the growth, micro- and macroconidia production were similar with slight differences among the salts. Microconidia were produced within a relatively wide range of salt concentrations whereas macroconidia were produced within a range of salt concentrations narrower than those for microconidia. At about 8% or more, the production of micro- and macroconidia tended to decrease in number and was replaced by arthroconidia. The results indicate that the utilization of high concentrations of salts is applicable not only for the identification of dermatophytes which lack characteristic conidia production but for the further clarification of the biological roles of each conidial form.

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Although incidences of mycosis have significantly increased lately in the ophthalmologic field, it is fairly rare to encounter a case other than mycotic keratitis.
Recently, however, an autopsy case of a 25-year-old-male was diagnosed as acute disseminated encephalomyelitis. During the course of treatment with antibiotics and steroid hormones, it was strongly suspected that he had fungal endophthalmitis in bilateral eyes. A fungal culture taken from the intraocular abscess of the right eye at the time of autopsy was negative. However, histologic examination showed an acute suppurative inflammation accompanying granulation tissues around the lesion. A few scattered candidal elements were found in the lesion by PAS reaction and immunohistological examination. The condition was diagnosed as endogenous fungal endophthalmitis, its histogenesis was discussed and relevant literature was reviewed.
Administration of antibiotics followed by abdominal surgery and a large quantity of steroid hormones is considered to have strongly related to the onset of this disorder. However, contrary to the Wests, it is very uncommon in Japan to encounter such a case with an onset obviously related to steroid hormones.

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We report a case of tinea capitis and tinea unguium in a 15 year-old girl caused by Microsporum canis which was supposed to have been contracted from a pet cat.
The proximal half of her left thumb nail was discolored and numerous short hyphae were seen with potassium hydroxide preparation. M. canis was isolated both from hair and nail specimens. She was treated by oral grilseofulvin (500mg per day) for one month and the scalp and nail lesions were healed after 1 and 4 months, respectively. This is the first reported case of onychomycosis caused by M. canis in Japan.

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Ketoconazole was administered to 12 patients with candidiasis. There were 5 cases of oral candidiasis, 2 of oral and esophageal candidiasis, 2 of candidemia, 1 of candidal meningitis and 2 of candiduria.
This agent was highly effective against superficial candidiasis, especially against oral candidiasis, the lesions being clinically cured within a few days of administration.
In the patients with candidemia, which had occurred as a complication due to an indwelling venous catheter, fever subsided and blood cultures were negative after the administration of ketoconazole. One patient died of acute renal failure following digitalis intoxication on the 11th day of administration and the post-mortem examination showed germ-tube forming Candida and phagocyted mycelia in the pulmonary vascular lesions due to the underlying disease (malignant rheumatoid arthritis). Candida circulating in the blood may localize in any organ where a locus minoris resistentiae due to an underlying disease is present and gives rise to local infections such as pneumonia. Early treatment is therefore important. In another case where candidemia was accompanied by candidal suppurative thrombophlebitis during prolonged intravenous therapy, excision of the affected vein cured the patient.
Candidal meningitis was cured by combined administration of ketoconazole and flucytosine. It is necessary to change the site where the catheter is inserted, since this disease occurs concurrently following techniques such as cerebrospinal fluids drainage. Ketoconazole has a low penetration into the cerebrospinal fluids; high-dose therapy or combined therapy using ketoconazole with amphotericin B and/or flucytosine should be considered.
Favorable results were obtained with ketoconazole treatment against candiduria, but additional studies are necessary. No severe side effects were observed. Our findings indicate that ketoconazole is potentially effective in candidiasis.

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We obtained two cell forms of a dimorphic fungus, Candida albicans, the yeast-like (Y) and mycelial (M) forms, by growing them in Sabouraud's glucose medium and methionine containing medium, respectively. Spheroplasts were prepared from each cell type using a cell wall lytic enzyme (Zymolyase 100, 000) and then membrane fractions were isolated after hypotonic disruption. Membrane suspensions were fractionated by differential centrifugation under 160×g, 10, 000×g and 100, 000×g and the chitin synthetase activity in each fraction was determined. The 100, 000×g pellet fraction showed the highest activity, being enriched four-fold in the Y-form cells and five-fold in the M-form, as compared with the activity of total homogenate. With regard to enzyme activity-growth relationships, both forms of cells showed highest activity in the mid-logarithmic stage. Effects of divalent metal cations, pH, Km, heat stability and activators such as digitonin and several surfactants were investigated for chitin synthetase activity. No marked changes were observed in the biochemical properties of chitin synthetases between M and Y-forms, suggesting that the observed difference in their enzymic activity was due to the quantitative rather than the qualitative difference of chitin synthetase.

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710674-S, a new imidazole derivative, exhibited potent activity against common dermatophyte species. Candida and other yeasts required moderate MIC values for inhibition. 710674-S, clotrimazole (CTZ) and econazole (ECZ) were similar in fungistatic activity against some standard strains of C. albicans, T. rubrum and T. mentagrophytes. The fungicidal activity of 710674-S was superior to that of CTZ for T. rubrum, and was somewhat inferior to those of ECZ and miconazole (MCZ) for C. albicans. Against clinical isolates of T. rubrum, 710674-S and CTZ had lower geometric mean MIC values than MCZ and ECZ. The mean MIC of 710674-S against the isolates of T. mentagrophytes was equivalent to that of CTZ and similar to that of ECZ. The clinical isolates of C. albicans were similarly susceptible to 710674-S and other reference imidazoles. Various factors were shown to affect the antifungal activity of 710674-S. Increase of inoculum size reduced the activity. Fungal susceptibilities tended to be enhanced with increasing pH of the medium. The activity was also lowered by addition of whole horse blood or plasma and erythrocytes.

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We previously reported that excessive iron promoted the proliferation of Candida in vivo. In a subsequent study of the influence of iron overload on deep-seated mycosis, experimental aspergillosis was induced in mice. Four groups received intravenous injections of colloidal iron (40 or 60mg/kg weight) for three consecutive days before intravenous inoculation of Aspergillus fumigatus conidia (5×10⁶ or 1×10⁷). The other two groups received the same numbers of Aspergillus conidia without iron overload. All six groups were observed for 28 days.
In both 5×10⁶ and 1×10⁷ Aspergillus conidia inoculation, there were marked differences in mortality between the group without iron and the groups with iron administration (40 or 60mg/kg weight), i. e., the mortality was higher in the groups with iron; however, this did not correlate positively with the amount of iron. In the groups with iron, increased serum iron and iron saturation were demonstrated, but there was no significant difference in iron saturation between them. The Aspergillus lesions were observed in the kidneys of all mice with inoculation (1×10⁷) after iron administration.
These results indicate that iron overload promotes the proliferation of Aspergillus as well as Candida in vivo, and that there may be no significant difference in the proliferation of Aspergillus similar increases of iron saturation, regardless of the amount of iron administered.

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