Yeast tissue phase of Emmonsia pasteuriana inoculated in golden hamster by intratesticular way.

The scope of our study was to present an experimental model reproducing the dimorphic yeast-like population (as for Histoplasma capsulatum, Blastomyces dermatitidis) similar to that observed in the cutaneous biopsy of an Italian woman who had never traveled abroad, being intravenous drug user and HIV positive for 10 years, finally infected with the new dimorphic fungus Emmonsia pasteuriana. Experimental inoculation was unsuccessful by intraperitoneal (i.p.) and intravenous (i.v.) ways in a mouse and in a guinea-pig model inoculated by cutaneous or subcutaneous routes, reason for that we chose the golden hamster, highly sensitive to dimorphic fungi as agents of systemic mycoses as histoplasmosis, blastomycosis, sporotrichosis, penicilliosis marneffei, paracoccidioidomycosis when the inoculation was done by intraperitoneal route. We inoculated young golden hamsters by i.p. and intratesticular ways. Only by this last route we reproduced an orchiepididymitis with necrosis, haemorrhages and a polymorphic yeast-like population similar to the polymorphism observed in the cutaneous biopsy of the patient. The intratesticular affinity of E. pasteuriana provided an interesting model for this infection.

Yeast tissue phase of Emmonsia pasteuriana inoculated in golden hamster by intratesticular way.

The scope of our study was to present an experimental model reproducing the dimorphic yeast-like population (as for Histoplasma capsulatum, Blastomyces dermatitidis) similar to that observed in the cutaneous biopsy of an Italian woman who had never traveled abroad, being intravenous drug user and HIV positive for 10 years, finally infected with the new dimorphic fungus Emmonsia pasteuriana. Experimental inoculation was unsuccessful by intraperitoneal (i. p.) and intravenous (i. v.) ways in a mouse and in a guinea-pig model inoculated by cutaneous or subcutaneous routes, reason for that we chose the golden hamster, highly sensitive to dimorphic fungi as agents of systemic mycoses as histoplasmosis, blastomycosis, sporotrichosis, penicilliosis marneffei, paracoccidioidomycosis when the inoculation was done by intraperitoneal route. We inoculated young golden hamsters by i. p. and intratesticular ways. Only by this last route we reproduced an orchiepididymitis with necrosis, haemorrhages and a polymorphic yeast-like population similar to the polymorphism observed in the cutaneous biopsy of the patient. The intratesticular affinity of E. pasteuriana provided an interesting model for this infection.

In vitro antifungal activity of sertaconazole.

The antifungal activity of 7-chloro-3-[1-(2,4-dichlorophenyl)-2-(1H- imidazol-1-yl)ethoxy-methyl]benzo[b]thiophene (sertaconazole, FI-7045, CAS 99592-32-2) versus miconazole has been studied in vitro against yeast-like fungi, dermatophytes and other filamentous fungi. Candida albicans was very sensitive to sertaconazole both in serotype A and serotype B strains (MIC = 0.21 micrograms/ml). Sensitivity of Candida non albicans species (MIC = 0.17 microgram/ml), Torulopsis (MIC = 0.09 microgram/ml) and Trichosporon (MIC = 0.09 microgram/ml) was also remarkable. For dermatophytes, partial inhibitions were observed at concentrations of 0.04 and 0.09 microgram/ml, the 50% inhibition ranging between 0.36 and 12.56 micrograms/ml for most strains. Filamentous opportunistic fungi were less sensitive to azoles, although sertaconazole MICs were lower than those of miconazole. Sertaconazole also proved to possess a remarkable fungicidal activity on all strains of Candida albicans under study.

[Current status and trends in quality control in parasitology and mycology]. / Réalisations et perspectives du contrôle de qualité en parasitologie et mycologie.

The survey of the results of the control quality in Parasitology and Mycology showed in general an improvement in the correct diagnosis for the specimen analysed (preparations of parasites, smears, stools, sera, fungal cultures). The wrong diagnosis of Ascaris lumbricoides eggs in stools diminished from 5% to 1.5%. The trichrome Gomori-Wheatley stain technic on smears in PVA was introduced. 16 reference or national standards sera for the parasitological serology, including 6 for toxoplasmosis and one for candidiasis were established. The increasing number of participants (more than 4,000) and particularly for the serology of toxoplasmosis showed the interest of the biologists for the quality of their tests.

Activity of cilofungin (LY 121019), a new lipopeptide antibiotic, on the cell wall and cytoplasmic membrane of Candida albicans. Structural modifications in scanning and transmission electron microscopy.

Cilofungin, a new biosemisynthetic analog of echinocandin B, inhibits the synthesis of beta-(1,3)-glucan resulting in severe modifications of the cell wall and cytoplasmic membrane of sensitive organisms. The morphological modifications to budding yeast cells, pseudomycelium, mycelium and germ tubes of Candida albicans were studied by scanning and transmission electron microscopy after 3 and 16 h exposure to cilofungin. Changes in yeast cell morphology were apparent after 3 h in 0.1 microgram ml-1 cilofungin but were more marked in 1 and 10 micrograms ml-1 cilofungin. Most of the yeasts failed to separate and formed aggregates. Cracks and discontinuities were present in the cell wall and the cell membrane became undulated and fractured. Inclusions into the periplasmalemma space were observed, along with a release of cellular components. An important inhibition of germ tube formation was noted and the structure of true mycelium and pseudomycelium was severely modified. The budding area of yeast cells was particularly susceptible to damage by cilofungin.

[Current role of deep mycoses in infectious pathology]. / Place actuelle des mycoses profondes dans la pathologie infectieuse.

Deep mycoses present new aspects characterized by deep, visceral mycotic localisations and septicemia, particularly in immunocompromised conditions. In immunodepressed patients (leukaemia, transplantation), the granulopenia descending to 500 elements/ml leads not only to invasive aspergillosis and candidosis but also to infections due to opportunistic fungi exceptionally or never seen formerly. AIDS favours opportunistic fungi related to defective cellular immunity as Cryptococcus neoformans, responsible of severe meningoencephalitis and septicemia, as Candida albicans responsible of thrush and oesophagitis, but also true pathogenic fungi (Histoplasma capsulatum) becoming opportunistic in such conditions. C. albicans provokes in heroin addicts a new septicemic syndrome with cutaneous, ocular and osteoarticular lesions and in leukaemic patients hepatic micro-abscesses soon after the neutropenic phase induced by chemotherapy. New methods for immunologic diagnosis (research of circulating fungal antigen), for clinical diagnosis (scanning, magnetic resonance). New strategy of antifungal chemotherapy (itraconazole, fluconazole) allow to a better knowledge and control of this new infectious pathology.

[Histoplasmosis and other imported mycoses in 1989]. / Histoplasmoses et autres mycoses d'importation en 1989.

The most common systemic mycoses imported into France are the histoplasmosis caused by H. capsulatum, which comes from Black Africa and from the French overseas departments and territories (Guyane, Martinique, Guadeloupe, New Caledonia), and the histoplasmosis caused by the larger H. duboisii, which is exclusively Central African. In recent years, histoplasmosis has become an opportunistic infection in immunocompromised patients, particularly those with AIDS. Blastomycosis, imported from North America as well as from North Africa and Central Africa, and paracoccidioidomycosis, imported from Latin America, are pulmonary mycoses with cutaneous manifestations on the face and extremities and with various deep localizations which often follow a chronic course. Coccidioidomycosis, strictly limited to the desertic regions in the western part of the American continent, is also a pulmonary mycosis with multiple granulomas in the skin, bones, lymph nodes and meninges. Penicilliosis caused by Penicillium marneffei is a mycosis from South-East Asia which has recently been observed in European AIDS patients who had travelled in that part of the world.

Fluconazole in the management of oropharyngeal candidosis in a predominantly HIV antibody-positive group of patients.

Seventy-one patients with oropharyngeal candidosis received treatment with fluconazole given as a single 50 mg capsule once daily. Of these patients 61 were HIV-antibody positive. Candidosis had been present in nearly all patients for a least one month prior to fluconazole treatment. The duration of daily therapy was 5-20 days and in many cases this was followed by a period of maintenance treatment using 50 mg fluconazole every 48 h. In all 42 symptomatic patients, clinical resolution of the infection occurred within 7 days. Significantly, this included the disappearance of dysphagia in four patients with proven candidal oesophagitis. A marked reduction, or eradication of oral yeasts occurred concomitantly in virtually all patients. Fluconazole was well tolerated by all patients and there were no significant changes in haematological or hepatic parameters that could be attributed to the drug. The results suggest that fluconazole is an appropriate treatment for oropharyngeal candidosis and comparative studies with other agents should now be conducted.

Paracoccidioidomycosis in nude mice: presence of filamentous forms of the fungus.

Congenitally athymic nude mice (nu/nu) and their phenotypically normal littermates (nu/+) were intraperitoneally infected with yeast cells of a strain of Paracoccidioides brasiliensis. The nude mice developed a severe and generalized infection with an intense parasitism of several organs, accompanied by a low-grade of tissue reaction. The lesions were characterized by abundant yeast-like cells of the fungus, and in some animals, numerous hyphal forms could be well visualized. In control animals, infection was moderate, almost exclusively restricted to the area of inoculation, and the lesions presented few parasites surrounded by an inflammatory response. Filamentous forms of the fungus were never encountered in these animals.

Mannan-specific and mannan-induced T-cell suppressive activity in patients with chronic mucocutaneous candidiasis.

We have studied T- and B-cell responses to antigens of Candida albicans in 18 patients suffering from chronic mucocutaneous candidiasis. We have shown that in vitro production of antibody to one of these antigens, mannan, was absent during the active phase of the disease and that this absence was consequent to the activation of specific CD8(+) and CD8(-) suppressor T lymphocytes. Such activation was also observed when control T lymphocytes were incubated in the presence of monocytes and a high concentration of mannan. This suppressive effect was specific to antigens of Candida albicans, was radiosensitive, and was not consequent to the secretion of prostaglandin E2. It appeared as well that the induction of these suppressor T cells was HLA-DQ restricted. The suppressor T-cell activity induced by antigens of Candida albicans in vitro is thus comparable to the suppressor T-cell activity observed in vivo in patients affected with chronic mucocutaneous candidiasis. Defective handling of mannan by monocytes could result in the accumulation of mannan, resulting in the activation of specific T suppressor cells and in the consequent cellular immunodeficiency specific to Candida albicans. Successful treatment of the candidiasis resulted in complete correction of the immune abnormalities.

Enzyme-linked immunosorbent-assay (ELISA) for IgG in bagasse workers' sera: comparison with counter-immunoelectrophoresis.

An enzyme-linked immunosorbent-assay (ELISA) for the detection of antibodies against Thermoactinomyces sacchari associated with bagassosis has been described and compared with the counter-immunoelectrophoresis (CIE) assay in forty-five bagasse workers; twenty-six of whom had symptoms consistent with bagassosis, and ten who were normal blood-bank donors. The ELISA was more sensitive than CIE in detecting antibodies against the double dialysis antigen used. There was a significantly (P less than 0.05) greater number of ELISA-positive individuals (82%) than those who were precipitin positive (60%). Results of the ELISA also gave a significantly better correlation (P less than 0.05) with the clinical diagnosis (88%) than did the precipitin test results (58%). The ELISA was useful in quantitating antibodies in the sera. The symptomatic group of bagasse workers did not have significantly higher titres in the ELISA than the group of exposed but asymptomatic subjects. We conclude that the ELISA is a sensitive and specific test, which is readily available and widely applicable for the detection of immunization in bagasse workers.

Entry of ketoconazole into Candida albicans.

To define characteristics that determine the entry of ketoconazole (KTZ) into Candida albicans cells, we studied the uptake of [3H]KTZ. The cells rapidly and markedly concentrated the drug: 30% of the final 80-fold intracellular concentration was attained in less than 1 min, and greater than 60% was attained in 10 min. Penetration of [3H]KTZ at an extracellular concentration higher than 0.1875 microM (0.1 microgram/ml) occurred by a simple diffusion mechanism. At lower concentrations, accumulation of the drug was an active, energy-requiring process, dependent at least in part on glycolysis, and pH dependent (optimal pH, 6.6). The active transport system had a high binding affinity (Km = 50 nM) and a high maximum velocity of uptake (Vmax = 1.4 mumol min-1 10(-7) cells). It was not possible to displace intracellular [3H]KTZ with high concentrations of unlabeled KTZ or other antifungal agents. These findings suggest that KTZ is rapidly taken up, highly concentrated, and tightly bound to cellular components of C. albicans.

[Immunization of bagasse workers in Réunion]. / Etude de l'immunisation des travailleurs de la bagasse à La Réunion.

We studied the immunological status of 45 bagasse workers from La Réunion to Thermoactinomyces sacchari. Twenty-six patients (58%) had a history of symptoms suggestive of sensitization to bagasse dusts; 19 (42%) were asymptomatic cases. Serum IgG was detected in 37 (80%) of the case patients and in 23 (88%) of the symptomatic cases. However, there was no significant difference in mean serum IgG titers of symptomatic (2.2 +/- 0.1) and asymptomatic cases (2.3 +/- 0.1). Analysis of isotypic specificity of IgG showed only IgG1 (71%) and/or IgG3 (60%) subclasses. Serum IgM and serum IgA were detected in only 7 (16%) and 2 (4%) of the case-patients, respectively. The detection of IgG was not found to correlate with either the case-patients' age, ethnicity, use of tobacco and alcohol, or their frequency, duration and amount of dust exposure. Therefore, the sensitization to T. sacchari antigens in bagasse dusts appears to be mainly mediated by IgG, subclasses 1 and 3, but is not pathogno monic of clinical symptomatology.

Evolution of antifungal agents: past, present, and future.

Important progress has been achieved in antifungal chemotherapy in recent years. Two groups of drugs are now used: those produced by various organisms and those made synthetically. In the first group, only amphotericin B (1956) administered systemically is active in numerous deep mycoses. Although toxicity limits the use of amphotericin B, it is still the drug of choice for systemic mycoses. Griseofulvin was the first agent used for oral treatment of dermatophytoses. The introduction of flucytosine began a new era in chemotherapy; however, although flucytosine is orally administered and rapidly distributed, its antifungal activity is limited to cryptococcosis and systemic candidosis. The rapid induction of flucytosine-resistant mutants led to the development of treatment regimens of amphotericin B plus flucytosine. With the development of imidazole derivatives in 1969, a new generation of azole antifungal agents has emerged. Of these, only ketoconazole was orally active. New azole derivatives and triazoles have been synthesized, but only itraconazole has been successful in the treatment of superficial and deep mycoses in humans. Future trends for the development of agents with fungicidal activity, wider spectra, and better distribution are proposed. The association of immunotherapy with antifungal chemotherapy may offer new treatments for fungal infections in immunocompromised patients.