Vincent J. Derbes

Isolation of a Hemolytic Component of Fire Ant Venom

A crystalline hemolytic principle, shown to be a constituent of fire ant venom and having the properties of an amine, was isolated from crude extracts of whole ants. The chromatographic procedure of isolation is described, and a preliminary report is given about some properties of the substance.

Response of tuberculin skin test to ACTH and cortisone in tuberculous guinea pigs.

Summary (1) ACTH and Cortisone when given in proportionately large doses modified but did not abolish cutaneous tuberculin reaction in guinea pigs infected with virulent tubercle organisms. (2) Following administration of ACTH and Cortisone the histopathologic changes consisted in a quantitative diminution in the inflammatory exudate rather than a qualitative change in its cytologic structure.

THE QUESTION OF IMMUNITY IN RINGWORM INFECTIONS

There is some indication that an immune response against dermatophytes is developed in experimental animals in view of the early work of Delamater’ and Delamater and Benham2 with Trichophylon menfagrophytes and of the more recent work of Reiss and Leonard3 with Microsporum canis and of Keeney and Huppert4 with T . menfagrophyfes. Also, Huppert and Keeney5 felt that they had demonstrated an acquired resistance against dermatophyte infections in human volunteers previously immunized with antigens of T. menlagrophytes. For the most part, however, the immunity developed has been partial in that the course of the disease following immunization was only shorter and milder than that normally observed. The role of such an altered response under natural conditions is nebulous, in part because of so-called “natural resistance” to dermatophyte infections that has been described by many, particularly well by Barlow.G I t is generally assumed that most persons are exposed to dermatophyte infections, yet relatively few develop clinical disease. This is well exemplified by the study of Kligman? who found that only 5 per cent of a group of institutionalized children had acquired a natural infection during an epidemic of tinea capitis caused by Microsforon audouini, despite the intimate and prolonged contact this situation provided. The factors that limit the spread of such epidemics would seem to be more complex than merely the natural resistance of certain individuals and might well be strongly influenced by other factors such as infectivity and virulence of the strain, size of the inoculum received by the individual, and the effect of local trauma, as well as the possibility of altered response following infection. For example, it is our impression, based more on speculation than data, that M . audouini, although perhaps more virulent than other of the causative agents of tinea capitis, may not be a5 infectious. I t was our desire to determine the presence, or absence, of immunity under natural conditions following recovery from naturally acquired tinea capitis. The observation that children usually do not have second bouts with this disease would seem a t first glance sufficient evidence for a concept of acquired immunity. However, since the opportunity for first infections often is not great, the failure to acquire a second infection might well be attributable to lack of opportunity rather than immunity. Of 718 children treated for tinea capitis in the Tulane University clinic during a threeyear period, not one returned with a second infection, despite entirely free medical care, including medication. At the time griseofulvin first became available, a deliberate effort was made to set up studies to explore the possibility of immunity following infection. I t seemed to us that treating one sibling and then leaving that child exposed to one or more untreated children would provide a long-awaited opportunity. * The work described in this paper was supported in part by Grant F, 1224 from the National Institute of Allergy and Infectious Diseases, Public Health Service, Bethesda, Md.

ICHTHYOSIS–LAMELLAR EXFOLIATIVE TYPE

Nine cases (six males and three females) of ichthyosis of the lamellar exfoliative type occurred among 22 offspring in three related families of German origin. All six parents have a common ancestor and are first cousins or fourth cousins once removed. Inheritance is by an autosomal recessive gene with 100%penetrance. This type of inheritance is compatible with the results of a n analysis based on all similar cases found in the literature. We believe different autosomal recessive genes cause the harlequin fetus and types of lamellar exfoliation with associated anomalies.

CANDIDA ALEICANS ONYCHOMYCOSIS—A STUDY OF FIVE MODES OF THERAPY

Materials and Methods In each case the clinical diagnosis was confirmed by direct examination as well as culturally. The presence of diabetes mellitus was investigated in customary fashion and only nondiabetic patients were included in the study. Each infected nail was then treated by one of five procedures: 1) evulsion; 2) evulsion followed by packing with amphotericin B powder ; 3) superficial X-ray therapy; 4) injection of the posterior nail fold with amphotericin B and triamcinolone acetonide, or 5) packing the pocket of infection, formed by the detachment of the posterior nail fold from the nail plate, with a mixture of equal parts of amphotericin B and mixed antibiotic powders (bacitracin, neomycin and polymyxin) . The importance of keeping the hands dry at all times was im-

Further characterization of hemolytic component of fire ant venom. Mycological aspects.

Summary The crystalline hemolytic component of fire ant venom was tested against 21 organisms, mostly human pathogens, by placing a crystal in direct contact with Petri dishes seeded with a different organism. Anti-mycotic action was demonstrated by a lack of growth immediately surrounding the crystal with the following genera: Blastomyces, Candida, Cladosporium, Cryptococcus, Geotrichum, Hormodendrum, Microsporum, Nocardia, Phialophora, and Trichophyton.