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Yeasts wcrc observed to be of common occurrence in subtropical marine waters and scdimcnts and with indwelling plants and anilnals. The most prevalent types prcscnt in all environments were oxidative, asporogcnous forms which expressed a growth requircmcnt for one or more vitamins. Certain distinctive metabolic attributes of yeasts were associated with environmental distribution. The incidental yeast flora on marine vegetation was uniformly low in number and consistent with the spccics isolated from surrounding waters and scdimcnts. The species found within the intestinal contents of fish appcarcd to be of transitory nature and restricted in population density. Yeasts have been found in significant numbers in the waters of those oceans and seas that have been systematically studied. The enumeration and taxonomy of yeasts in Atlantic subtropical marine waters and sediments has been reported by Fell, et nl. ( 1960) wherein the influence of terrestrial run-off on the yeast populations of estuarine areas and the presence of yeasts in planktonic masses and benthic sediments was established. As a further and continuing study of the ecology and systcmaties of marine fungi, selected aquatic habitats were examined intensively for the occurrence of yeasts to establish possible sites of active growth and reproduction of these microorganisms. In this work, quantitative and qualitative studies of the indigenous yeast flora isolated from diverse marine waters, sediments, and associated plants and animals were undertaken. MATERIALS AND Ml~ITIODS

The humoral mechanisms of natural resistance to pathogenic fungi have been the subject of increased study in recent years. Lorincz and coworkers (1) demonstrated that fresh human serum contains a potent factor which inhibits the growth of dermatophytes. This substance was shown to be of unstable nature and dialyzable. The inhibitory effect was present in all sera tested and was operative in both the in vivo and in vitro environment. Blank, et at. (2) studied the role of serum on dermatophytes growing in cultured human skin. It was observed that the superficial fungi were restricted to the stratum corneum by the presence of fungistatic components in the serum employed as a constituent of the medium used to maintain the skin explants. Insufficient concentration or absence of serum permitted the fungi to invade all regions and strnctures present in the living skin. In 1959, Roth and coworkers (3) confirmed and extended the work of Lorincz and reported the effect of human serum on the growth of Candida albicans. It was observed that the sera of normal adults possesses a high capacity to inhibit the growth and reproduction of this pathogenic yeast in a medium which alone supports luxuriant growth. The inhibitory activity was greatly diminished in blood specimens obtained from umbilical cords and from infants during the first 8 to 10 weeks of life. Paired maternal sera demonstrated inhibitory levels equivalent to those of normal adults at concentrations as low as 10 per cent. After the third month of life a rapid increase in anti-candida titer was noted and blood specimens taken after the sixth to eighth month approached the inhibitory levels obtained with normal adult sera. Heating of normal serum for one hour at 56° C. did not significantly reduce its activity nor did absorption with homologous cell suspensions for 6 hours affect the fungistatie capacity. It was

Yeasts were isolated from twelve established sites in the North Sea from 1964 to 1966. A percentage frequency of 99% with populations varying from 3000 viable cells/L was observed. This mycota was characterized by considerable spatial and temporal fluctuation, with the dominant yeast present being the ascosporogenous species, Debaryomyces hansenii. This taxon, as well as other common North Sea yeasts, e.g., Rhodotorula rubra and Candida diddensii, have been reported frequently from other marine locales. Noteworthy concentrations of yeasts, especially D. hansenii, were observed during summer months, often in association with various stages of development of the dinoflagellate, Noctiluca miliaris. The population dynamics of the North Sea yeasts are discussed in relation to similar studies of other marine environments.

SummaryA simple method is described for the production of rapidly progressive lethal infections. It consists of the administration of two readily available agents in combination, cortisone and x-radiation, to laboratory animals in preparation for test within the next 24 hours as recipients of a microorganism. Cortisone and x-radiation each over a wide dosage range act synergistically to potentiate the enhancive effect that may result from the employment of either agent singly. The result of this effect is a remarkable alteration in the susceptibility of a test animal to infection by any of a variety of infectious agents, as evidenced by rapid weight loss, death and extensive histopathological lesions. The ready applicability of the method is illustrated in this paper by experiments that utilized four microbiological agents: poliomyelitis virus, a Coxsackie virus, Candida albicans, and Blastomyces dermatitidis. The experimental studies that employed these agents and the findings for other viruses, bacteria...

A glycoprotein isolated form the cell wall of Trichophyton mentagrophytes was assessed for its cross-reaction with human blood group isoantigens. Rabbit antiglycoprotein antibodies agglutinated human erythrocytes of blood groups A 1 and A 2 , and precipitated Blood Group Substance A in agarose gels. Erythrocytes of blood group B were only slightly agglutinated, and O(Rho + ) and O(Rho - ) erythrocytes were not. Additionally, the glycoprotein was shown to specifically inhibit isoagglutination of erythrocytes of group A. Partial identity between the glycoprotein and a crude extract of the fungus was demonstrated by immunodiffusion. Analyses revealed the glycoprotein to be composed of approximately 17% protein and 80% carbohydrate. The glycoprotein was found by indirect immunofluorescence to be located in the mycelial cell wall. The possibility that cross-reacting antigens may lead to a chronic, spreading infection is discussed.

Griseofulvin, an antibiotic obtainable from at least four kinds of Penicillium, has been found effective in certain experimental fungous infections of animals as well as in fungous diseases of man. It was used in 200 patients with superficial fungous infections at 311 sites of major involvement. The organism most frequently found was Trichophyton rubrum, identified in 185 sites. The dosage of griseofulvin varied from 0.5 to 1.0 Gm. by mouth. One gram per day is recommended. When the lesions did not involve the nails, palms, or soles, three weeks of therapy usually was adequate. Even with lesions of the palms and soles, relief from itching occurred in two to six days; vesicles and scales disappeared and cultures usually became negative in two to six weeks. It was necessary to keep in mind the fact that nails grow slowly and that the fungous infection may be superposed on other disease. Until more experience with this drug accumulates, monthly blood counts are advised, but in this series no significant manifestations of toxicity were noted.

Before studying the changes griseofulvin induces in Trichophyton organisms, it was necessary to define the normal fine structure of the fungus. No previous study of sections of these organisms has appeared. The preliminary report by Laden and Erickson 10 of the internal structure of Epidermophyton floccosum is the only study of its type with a dermatophyte. Several workers have attempted to visualize fungi in the electron microscope without sectioning the organisms, but these reports demonstrated little that could not be seen with a light microscope. 9,11,14,19 In ultrathin sections it was noted that algae (Allomyces) contain many of the most prominent intracellular structures described in animal cells, such as mitochondria with the classical mitochondrial membrane and cristae, as well as an organized cell nucleus with a double-structured nuclear membrane. 22,23 No typical ergastoplasm, however, was found in these aquatic phycomycetes. The most recent studies of bacteria reveal a thin cytoplasmic

Tinea nigra palmaris is an uncommon skin disease caused by the fungus Cladosporium Wernecki. In the western hemisphere nearly all reported cases have involved the palms; however, cases involving other areas of the body, such as the neck or thorax, do occur.1The asymptomatic macular lesions, neither elevated nor scaly, are brown or black, appearing like an India ink2or silver nitrate stain.3The disease must be differentiated from nevi, contact dermatitis, pigmentation of Addison's disease, and drug eruptions. The pigmented lesions of photodermatitis due to bergamot or lime oil can be differentiated easily since they never occur on the palms.4 Only five cases of tinea nigra acquired in the United States have been reported, although cases acquired in Brazil,5Cuba,2Panama,6and Puerto Rico7in the western hemisphere are described in the literature. The first case to be reported from the

Yeasts of the genus Rhodotorula obtained from subtropical marine environments were classified by comparing them critically with type and authentic cultures. No distinctive metabolic differences ascribable to environmental influence were observed in comparing marine and terrestrial isolates. Identifications of species were based on requirements for vitamins, ability to assimilate selected carbohydrates, and capacity to utilize nitrate nitrogen. The difficulties encountered in delimiting species by relying entirely on established metabolic characteristics are presented. Recharacterization of available type cultures indicates the existence of synonymy and the occurrence of divergent metabolic strains within recognized species.

Buck, John D. (University of Miami, Miami, Fla.), Donald G. Ahearn, Frank J. Roth, Jr., and Samuel P. Meyers . Inhibition of yeasts by a marine bacterium. J. Bacteriol. 85: 1132–1135. 1963.—Although investigations have shown the widespread occurrence of yeasts in the marine environment, notably members of the genus Rhodotorula , studies of a marine amphipod community revealed few, if any, pink yeasts. A gram-negative bacterium (designated AEB, a member of the genus Pseudomonas ) isolated from the amphipod habitat showed marked selective ability to inhibit yeasts of both terrestrial and marine origin. Activity was demonstrated with both live cultures of the bacterium and untreated cell-free filtrates. Variously extracted and treated filtrates of the isolate have shown divergent patterns and spectra of inhibition of species of the genus Rhodotorula and of other genera.

The results of a number of investigations of the effects of ionizing radiation on fungi have been contradictory. Pearson et al. 1 found that 1,100 r of high-voltage x-ray or exposure for 24 hours to 20μc. of radioactive iodine or radioactive phosphorus caused partial to complete inhibition of growth of a number of fungi, such as Epidermophyton floccosum, Microsporum audouini, Microsporum gypseum, Trichophyton rubrum, and Trichophyton violaceum. Lewis et al. 2 exposed M. gypseum and Trichophyton mentagrophytes to 4,800 r of x-ray either in a single dose or in repeated doses and found a speeding up of maturation as evidenced by a more rapid development of the core of the fungus culture. Comparable doses of soft radiation showed no such enhancing effect. Lawrence et al., 3 using Co 60 as a source of radiation, found that, for the production of sterility, Aspergillus niger required a dosage of

In a living host the selectivity of dermatophytes for the keratin-containing dead outer structures of the skin is so extreme as to engender the terms keratinophilic and necrophilic for these organisms. The present study provides data to suggest that there are humoral factors which ordinarily bar invasion by dermatophytes but that under appropriate circumstances the organisms will readily invade living nonkeratinous skin. The superficial habitat of the ringworm fungi is not a result of favorable nutritional factors in the keratinous layers. In the test tube, dermatophytes grow as vigorously in other media as they do in one containing only keratinous materials, such as powdered callus, or hair or nail clippings. Jacobs and Lorincz found little difference between growth of dermatophytes on the corium side or the cornified side of buttons of excised and killed human skin. 12 Nonetheless, even when the organisms gain entrance

SummarySupersonic vibration of viable C. albicans cells released a substance lethal to mice treated with chlortetracycline. In the absence of antibiotic the cell-free preparation was inactive. The combination of supersonic extract with chlortetracycline was highly lethal to mice, that with oxytetracycline was slightly active, while that with chloramphenicol or streptomycin was inactive. Evidence was presented for the combined toxicity of viable C. albicans cells and chlortetracycline to diverse animal species.

It is generally agreed that the oral administration of griseofulvin results in the incorporation of the antibiotic into the keratinized tissues of the skin, hair, and nails. The presence of griseofulvin in these structures inhibits the growth and further invasion of sensitive dermatophytes, and results in the eventual elimination of the fungus. At the present time the mechanism by which griseofulvin is incorporated into these keratinized tissues is not known. It would appear that some of the antibiotic is firmly bound in the cornified elements, while the remainder is not so bound and may be eliminated by sweating, maceration, insensible perspiration, sebaceous secretion, or other normal functions of the skin. Gentles 1 fed guinea pigs 40 mg/kg. of griseofulvin for 23 days. At the end of this period hair clippings were extracted first with water and then by refluxing with methanol. One gram of hair yielded 5μg. to 6μg. of

The human small and large intestine were studied for viruses, bacteria, and fungi in 29 adults with acute diarrheal disease. No etiologic agent was found in 83% of the cases. The most striking finding in these patients was a marked increase in the number of bacteria in the jejunal aspirates. No viruses were isolated in any of the jejunal, ileal, or fecal specimens.