E. S. Beneke

Dermatophytosis of the scalp: Incidence, immune response, and epidemiology

Tinea capitis remains a common infection among the pediatric population of North America. The ‘gray patch’ Microsporum audouinii infections of the 1950s have been supplanted by the ‘black dot’ ringworm of Trichophyton tonsurans. The clinical presentation of T. tonsurans infection is quite variable and may be related to specific host T-lymphocyte response. This dermatophytosis is most frequently incurred from contact with an infected child either directly or via a variety of fomites. Current studies indicate that an asymptomatic adult carrier state may also exist which could contribute to the morbidity of this mycosis.

Human pathogenic fungi recovered from Brasilian soil.

A total of 202 soil samples from areas around the cities of Belo Horizonte, Santos, São Paulo, Piracicaba and Itatiaia park were examined by various techniques for the presence of fungi that may be pathogenic to humans and animals. The fungi isolated were:Microsporon gypseum (40),M. cookei (2),Keratinomyces ajelloi (2),T. mentagrophytes (9),T. terrestre (49),T. verrucosum (2),Allescheria boydii (1),Aspergillus fumigatus (2),Candida albicans (21),Cryptococcus neoformans (4), andSporotrichum schenckii (4). Many of the pathogenic fungi were found in habitats where they might be expected to occur in relation to activities of humans and animals. The probable basis for the apparent absence ofParacoccidioides brasiliensis from soil samples was discussed. The following organisms have apparently been reported for the first time from soil samples in Brasil;T. mentagrophytes, T. terrestre, T. verrucosum, A. fumigatus, C. albicans, andS. schenckii.

Candida albicans resistance to 5-fluorocytosine: frequency of partially resistant strains among clinical isolates.

Resistance to 5-fluorocytosine was studied in 137 independent Candida albicans clinical isolates. Seventy-eight isolates (57%) were susceptible; 51 isolates (37%) were partially resistant; 8 isolates (6%) were highly resistant. All partially resistant isolates gave rise to variants which were highly resistant. Some susceptible isolates gave rise to variants which were highly resistant; two such isolates were shown to be heterozygous for resistance, and these isolates define a new type of heterozygote. A partially resistant isolate gave rise to resistant variants which were auxotrophic for lysine; this result was interpreted as preliminary evidence that the allele which determined resistance was linked to an allele which determined auxotrophy for lysine. It is suggested that heterozygotes constitute a source of preexisting mutant alleles which determine resistance, and that 5-fluorocytosine treatment of infections due to heterozygotes may result in significant selection for resistant variants. A simple screening procedure is described by which partially resistant strains may be recognized. Images

Influence of mucosal cell origin on the in vitro adherence of Candida albicans: Are mucosal cells from different sources equivalent?

The influence of collecting mucosal cells from various anatomical sites, and varying the date of collection and cell donor on adhesion of Candida albicans to human epithelial cells was examined by using an in vitro adherence assay. Examination of buccal mucosal cells from twenty-four donors showed statistically significant differences in the number of attached yeasts between individuals. Sex did not exert a significant influence on adhesion. Examination of buccal mucosal cells from ten donors collected on five different dates revealed that yeast attachment to mucosal epithelial cells varied significantly within subjects across time. Epithelial cells from some donors manifested greater date-to-date variations in yeast adhesion than others. Adherence of Candida to mucosal cells from three anatomical sites (mouth, vagina and urinary tract) collected from ten different donors was also tested. Yeast adherence to buccal cells was highest, lowest using urinary tract cells, while vaginal epithelium was intermediate. Adherence to mucosal cells from three sites was significantly different both within and between individuals although some subjects manifested larger variations than others. These data suggest that the in vitro adherence of Candida albicans is influenced by mucosal cell donor, date of collection and body site of origin. Mucosal cells from different sources do not appear to be equivalent in receptiveness to C. albicans and this might explain some of the discrepancies observed when adhesion studies performed by different investigators are compared. The existing need for a more uniform methodology with which to pursue studies on fungal attachment to mucosal surfaces is emphasized.

Segregation of 5-Fluorocytosine-Resistant Variants by Candida albicans

Spontaneous production of 5-fluorocytosine-resistant variants by three Candida albicans isolates is due to segregation from a preexisting heterozygous state. Images

Nutritional regulation of basidiocarp formation and mycelial growth of Agaricales.

The purpose of this treatise is to compend the carbon sources, nitrogen substances, vitamins, nonspecific substances, and environmental factors requisite for growth of the Agaricales fungi. Special reference is made to species belonging to the genera Agaricus, Pleurotus, Volvariella, Cantharellus and Lepista. Cultivation of Agaricales has been in progress for centuries in Europe and the Orient, although nutritional studies are relatively recent. Early production of mushroom species was a cottage industry; families produced mushrooms for their own consumption. In the caves of France large scale production developed from techniques utilizing family secrets to increase yields. The industry still has some inbred ideas and practices concerned with higher production rates. Somewhat nurtured by industry but more influenced by furthering scientific knowledge, species grown commercially and other Agaricales were inoculated in many plant and animal concoctions. Mycelium as well as basidiocarps were grown for the purpose of growth studies in vitro or for easier accessibility of the species for other areas of study. After growth and fruiting techniques were established for several species, defined media replaced the concoctions in genetic, anatomical, and physiological experiments. Topics discussed in relation to fructification and mycelial growth include crude substances, extracts, carbon sources, nitrogen sources, vitamins, growth promoting substances, carbon dioxide, pH, temperature, light, and gravity. Minerals are not considered in this paper. Taxa were identified as belonging to the Agaricales according

STUDIES ON CALVATIA GIGANTEA. I. GERMINATION OF THE BASIDIOSPORES

(WITH 4 FIGURES) The importance of the discovery of new tumor-retarding agents of potential value in the inhibition of human malignant growths has been emphasized in recent years through the rapid increase in laboratory and clinical testing of oncostatic substances. The discovery of such a substance(s) in Calvatia gigantea (Pers.) Lloyd developed from a study of higher fungi initiated by the late Dr. Eugene H. Lucas. Synonyms for Calvatia gigantea are: Lycoperdon giganteum Persoon, Bovista gigantea Nees, Lycoperdon Bovista Fries, Calvatia maxima Morgan, Calvatia Bovista MacBride, Calvatia primitiva Lloyd. As a possible method for obtaining strains which might produce a greater yield of the oncostatic principle(s), germination of C. gigantea spores was attempted. Stevens (1957) reported on environmental factors influencing in vitro growth of basidiomycetes and their elaboration of biologically active substances. A portion of his study included C. gigantea. Sedlmayr (1960) studied the nutritional requirements of C. gigantea and other Calvatia spp., with particular emphasis on vitamins. She demonstrated that each of the investigated strains was totally deficient for thiamine. Reports of attempts to germinate basidiospores of C. gigantea are relatively absent from the literature. Hoffman (1859) appears to have been the first investigator to report germination experiments on Lycoperdon spp. He reported that he germinated spores of L. constellatum Fr., L. gemmatum Batsch, and Bovista plumbea Pers. using a hanging drop technique. His paper mentioned the possibility that the germinat

Studies on Calvatia Gigantea. II. Factors Affecting Basidiospore Germination

SUMMARYSeveral, although probably not all, factors affecting germination of basidiospores of C. gigantea have been discussed: 1. Incorporation of 6 mg per liter of Chloromycetin into the germinatio...

Aquatic Fungi of Iceland: Comparative Morphology of Achlya Radiosa, A. Pseudoradiosa, And A. Stellata

Among the watermolds occurring in Iceland (8, 11), Achlya radiosa Maurizio (12) and A. stellata deBary (2) are surprisingly common. Neither species has been reported from North America, hence knowledge of them is based largely on European material. Of the two, A. radiosa is most easily recognized, though its taxonomic history is not unblemished with other names (10). Rogers and Beneke (15) noted the close resemblance of A. pseudoradiosa Rogers & Beneke to A. radiosa, but separated their species from Maurizios largely on o6spore number and size. Until the authoritative account by Dick (6) Achlya stellata was poorly defined, and the species had been treated (10) as a doubtfully valid taxon. Achlya stellata was cited in connection with A. pseudoradiosa, and considered (15) to be very closely allied to it. The Icelandic specimens of Achlya radiosa and A. stellata were variable in some prominent features. The degree of variation was explored, and for comparative purposes, we characterized the structure of specimens in cultures of A. pseudoradiosa (from Brazil; 3, 16). The resulting information was then applied to the systematics of the three species.

Extracellular enzymes of Blastomyces dermatitidis.

Blastomyces dermatitidis was investigated for the presence of several extracellular enzymes. This pathogenic fungus was found to produce acid- and alkaline-phosphatases in both liquid and solid media when growing in the yeast phase (37° C), but little or none of these activities was associated with the mycelial phase (25° C). Under the growth and assay conditions employed no alpha- or beta-glucosidases, alpha- or beta-galactosidases, N-acetylglucosaminidase, or fatty acid esterases were found. Blastomyces dermatitidis war für das Vorkommen von mehreren, extrazellulären Enzymen untersucht. Dieser pathogene Pilz bildete sauere und alkalische Phosphatasen sowohl in flüssigen als auch in festen Nährboden, wenn er in der Hefenphase (37° C) wuchs, aber eine geringe oder keine dieser Aktivitäten war mit der Myzelphase (25° C) verbunden. Unter den Bedingungen des Wachstums und der Versuchsanordnung sind keine Alpha- oder Beta-Glukosidasen, Alpha- oder Betagalaktosidasen, N-acetylglukosaminidase, oder Fettsäureesterasen gefunden worden.