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D Chabasse

Publications and source records attributed to D Chabasse.

At least 19 recordsLinked to original sources
PubMed2005

Trichophyton rubrum isolated from aids and human immunodeficiency virus-infected patients in São Paulo, Brazil: antifungal susceptibility and extracellular enzyme production.

BACKGROUND: In order to identify intraspecific variations in Trichophyton rubrum and to correlate them to the immunological status of the host, sixty strains isolated from AIDS, HIV-positive and HIV-negative patients were compared for the production of extracellular enzymes and for their susceptibility to several antifungal drugs. METHODS: The isolates were tested for their ability to secrete keratinases, proteinases, phospholipases, lipases and DNases. Likewise, we investigated their susceptibility to amphotericin B, ketoconazole, ciclopiroxolamine, griseofulvin, miconazole and tolnaftate. RESULTS: Variations in the Minimal Inhibitory Concentration (MIC80)) values were observed for all antifungals tested, but they were similarly distributed among the three clinical groups. Griseofulvin showed the most prominent differences among the three groups of isolates. Regarding enzyme secretion, all samples secreted keratinases and DNases, while none secreted phospholipases. Proteinases and lipases were secreted by some of them. CONCLUSIONS: The differences among isolates of the three groups were not statistically significant and therefore could not be ascribed to a given clinical status. Intraspecific variations similarly occurred in each group, irrespective of the immunological status of the patients.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Chrysosporium chiropterorum sp. nov., isolated in France, resembling Chrysosporium state of Ajellomyces capsulatus (Histoplasma capsulatum).

A fungus isolated in France from the fur of a bat, which produces characterized large tuberculate conidia (aleurioconidia) similar to those produced by the mycelial form of Histoplasma capsulatum (Ajellomyces capsulatus) is described. Colonies are white at first, but then become rosy buff from the centre outwards. Sectoring, resulting in the appearance of patches or areas of dark green mycelium, occurs spontaneously. Single-celled conidia are formed on undifferentiated hyphae, and may be sessile, or borne laterally on short stalks or producing in an intercalary position as it is the case in the genus Chrysosporium. This fungus is clearly distinguishable from any described species and is described as Chrysosporium chiropterorum sp. nov. C. chiropterorum, like H. capsulatum, produces gelatinase, and is non-keratinolytic but strongly ureolytic. Both species are associated with bat dwellings. C. chiropterorum differs from H. capsulatum by faster growth, pink or green colonies, and failure to produce microconidia as well as lack of conversion to a yeast phase in vitro at 37 degrees C.

Animals↗
PubMed2004

[Larva migrans].

Explore the source record for details and available documents.

Adult↗
PubMed2003

[Can we evaluate the frequency of onychomycosis?].

Onychomycosis represents one of the most common nail diseases. Difficult to bear by some patients, onychomycosis is one of the most frequent reasons for consulting by lack of uniformity and group-control a mycological centre. However, frequency of onychomycosis is miss appreciable. The studies of prevalence concern the general population (2 to 13 per cent according to the different authors) consulting a medical practitioner or specialist (dermatologist). Recent surveys done a large scale in Europe in adults indicated high prevalence: 20 to 30 per cent, depending on whether the investigator is a general practitioner or a dermatologist. In any case, all the studies concur in the opinion that onychomycosis has been in constant progression over the last twenty years. Rarely observed in children, frequent in adults, onychomycosis principally affects particularly the elderly. In Western Europe and in North America, onychomycosis involves principally the feet--especially in males. By contrast, in Southern Europe, in the Middle and Far East, the prevalence is highest in women's fingernails (often associated with paronychia). Among the factors promoting fungal nail invasion, some are local depending on the patient (trophic troubles and circulatory impairment overlapping of digits, etc.), some are due to general factors such as immunosuppression, diabetes mellitus or psoriasis. There are also behavioural factors (occupation, lifestyle, sports) which favor the meeting with the pathogenic fungus.

Adolescent↗
PubMed2002

[Candida endocarditis: retrospective study in 12 patients].

PURPOSE: Candida endocarditis are rare, with a poor prognosis. Actually, the principal problem concerns the growing incidence of nosocomial fungal infections. The objective of the present investigation is to assess a disease which risks becoming more pronounced in the future. METHODS: We have collected observations of Candida sp. endocarditis between 1985 to 1997 from three French university hospitals. RESULTS: Twelve of the observations fit the Duke criteria of acute endocarditis. Patients were eight men and four women, with a mean age of 46 years. An immunodepression was found in seven cases, and four patients were active drug addicts. Six had an underlying heart disease at risk to acute endocarditis. Candidemia risk factors were found in nine cases, with an average of 2.7 risk factors per patient. The fungal agents detected were Candida albicans (eight cases), C. tropicalis (one case), C. parapsilosis (two cases), and C. glabrata (one case). These vegetations were on aortic (seven cases), mitral (three cases), tricuspid valves (two cases) or in other areas (three cases), with multiple localizations (two cases). In three observations, vegetations were associated with myocardium abscesses. Eight patients had embolic complications, two had a cardiac insufficiency leading to death. The treatment was medical in all of the cases and combined with a surgical treatment in ten cases. The surgery was performed, on an average, 17 days after diagnosis, allowing seven surviving patients. Among them, five received a secondary prophylaxis and no recurrence was recorded. CONCLUSIONS: Prognosis remains severe because of the voluminous, friable and necrotic vegetations, which favor embolic migrations and which are not easily accessible to antifungals, which penetrate poorly into these vegetations. Therapy is based on a medical treatment combined with a valve replacement which needs to be done early on, and is followed by a relapse prevention which can occur several years after the initial episode.

Adult↗
PubMed2001

Evaluation of five commercial Sabouraud gentamicin-chloramphenicol agar media.

The diagnosis of fungal infections relies on the isolation of the causative agent by culture of clinical specimens. Among the different culture media, Sabouraud glucose agar remains the most widely used. The use of commercial culture media is highly recommended as good laboratory practice in clinical microbiology. Therefore, the comparative performance of five different Sabouraud gentamicin-chloramphenicol agar media, available commercially as plates, was investigated. A total of 124 strains encompassing 45 yeasts and 79 filamentous fungi were cultured. Colonies of the dermatophytes (28 strains) and some related keratinophilic fungi (6 strains) were of overall similar appearance or size on all five media. Conversely, all the Aspergillus strains tested (n=17) as well as a few other strains of Hyphomycetes (n=5/18) exhibited important differences in the colour of the colonies. Furthermore, growth of the members of Mucorace ae was also affected, with great differences in the diameter of the colonies observed. In addition, quantitative cultures of the yeasts revealed marked variations in the number of the colonies, or even no growth, for two Candida species, Cryptococcus species, and Trichosporon cutaneum. In conclusion, the only formulation that gave good results with all fungal types tested was the one from Becton Dickinson (France).

Agar↗
PubMed2001

[Yeast count in urine. Review of the literature and preliminary results of a multicenter prospective study carried out in 15 hospital centers].

Candida spp. are increasingly involved in nosocomial infections in severely ill patients and the diagnosis is difficult. In this context, the significance of candiduria remains unclear. Management of this condition is still equivocal, because of the lack of information about its natural history and its predictive value for disseminated infection. Little is known about the discriminant value of colony count. After a comprehensive review of the available published data, the preliminary results of a multicentric prospective survey in critically ill patients hospitalised in intensive care units are given. The aim of the study was to search for correlations between quantitative candiduria and known risk factors for disseminated candidiasis. There is a statistically significant correlation (p = 0.003) between heavy candiduria (> 10(4) cfu.mL-1) and high Pittet colonisation index (> or = 0.5). Quantification of candiduria could be useful to select patients at high risk for disseminated candidiasis.

Adult↗
PubMed2000

Clinical significance of Scedosporium apiospermum in patients with cystic fibrosis.

The incidence of airway colonization by Scedosporium apiospermum and of related sensitization was investigated prospectively in 128 patients with cystic fibrosis over a 5-year period, and results were compared with clinical data. Scedosporium apio-spermum, recovered from sputum samples in 11 of 128 (8.6%) patients, was the most frequent filamentous fungus after Aspergillus fumigatus. Counterimmuno-electrophoresis, used to detect scedosporiosis serologically, was positive in 27 of 128 (21.1%) patients. The discrepancy between the mycological and serological results may be related to immune cross-reactions between Scedosporium apiospermum and Aspergillus fumigatus. However, symptoms of allergic bronchopulmonary disease were observed in two patients chronically colonized by Scedosporium apiospermum. The results clearly demonstrate that the frequency of this fungus is largely underestimated and that it may trigger an inflammatory response, thus suggesting a pathogenic role in patients with cystic fibrosis.

Adolescent↗
PubMed1999

Association of a myosin immunoanalogue with cell envelopes of Aspergillus fumigatus conidia and its participation in swelling and germination.

A myosin immunoanalogue was identified in conidia of Aspergillus fumigatus by Western blotting, indirect immunofluorescence assay, and gold immunoelectron microscopy with two different antimyosin antibodies. The distribution pattern of this protein was followed during the early stages of germination. A single 180-kDa polypeptide, detected predominantly in a cell envelope extract, was found to cross-react with monoclonal and polyclonal antibodies raised against vertebrate muscle myosin. Immunoelectron microscopy permitted precise localization of this polypeptide, indicating that myosin analogue was mainly distributed along the plasma membrane of resting and swollen conidia. In germinating conidia, indirect immunofluorescence microscopy revealed myosin analogue at the periphery of germ tubes, whereas actin appeared as dispersed punctate structures in the cytoplasm that were more concentrated at the site of germ tube emergence. A myosin ATPase inhibitor, butanedione monoxime, greatly reduced swelling and blocked germination. In contrast, when conidia were treated with cytochalasin B, an inhibitor of actin polymerization, swelling was not affected and germination was only partially reduced. Butanedione monoxime-treated conidia showed accumulation of cytoplasmic vesicles and did not achieve cell wall reorganization, unlike swollen conidia. Collectively, these results suggest an essential role for this myosin analogue in the deposition of cell wall components during germination of A. fumigatus conidia and therefore in host tissue colonization.

Actins↗
PubMed1999

[Urticaria and parasites].

Urticaria has many etiology and during its exploration, it's important to mind about parasitic disease. The authors present briefly ten of them potentially associated with this eruption. For each disease (ascaridiosis, trichinellosis, fasciolosis, giardiosis, toxocarosis, anisakidosis, cercarial dermatitis, schistosomiasis, strongyloidosis, hydatidosis), they precise epidemiological situation for contamination and simple diagnosis approach.

Humans↗
PubMed1999

[Individual prevention of malaria caused by Plasmodium falciparum].

Individual protection against Plasmodium falciparum malaria is based on a simultaneous observance of a preservation from mosquitos bites during the night and an adapted chemioprophylaxis. It is suitable to personalize chemioprophylaxis advices according to the ground (intolerance to anti paludic drugs, drugs interactions, pregnancy...) to the context of the transmission (visited countries, seasons, resistance level of malaria strains) and at last the local way of the medical assistance under taken against this disease. Nevertheless, it is good to remind that there is no preventive mean which gives full protection by itself. All fever that happens after a trip in an endemic zone for malaria has to be considered firstly as due to malaria and investigations have to be made under this condition.

Animals↗
PubMed1998

[Cutaneous Scedosporium infection revealed by bullous-necrotic purpura].

BACKGROUND: Non-mycetomatous cutaneous scedosprium is an uncommon mycosis observed in immunodepressed subjects. We report a case with an inaugural presentation of bullous and necrotic purpura. CASE REPORT: A 79-year-old man on intermittent corticosteroid therapy for bronchospasm was admitted for bullous and necrotic purpura and fever. Subcutaneous nodules with a sporotrichoid aspect developed despite wide-spectrum antibiotics. Microbiology samples cultured on Sabouraud medium evidenced Scedosporium apiospermum. The pathogenic nature of the infection was proven on a skin biopsy showing numerous myceleal filaments with Gomori-Grocott staining despite negative PAS. No pulmonary involvement was evidenced. The patient was treated unsuccessfully with itraconazole. A Pseudomonas lung infection was fatal. DISCUSSION: Scedosporium apiospermum, an ubiquitous ascomycetes anamorphous to Pseudallescheria boydii, is the cause of a growing number of human infections due to widespread use of immunosuppressors. Skin and lung localizations predominate. The inaugural bullous and necrotic purpural skin manifestations in this case are unusual. In addition, the patient was only minimally immunodepressed and despite demonstrated in vitro sensitivity, itraconazole was ineffective clinically. Treatment is not well defined, but surgery is essential in combination with empirically chosen antifungals.

Aged↗
PubMed1997

Expression and identification of a laminin-binding protein in Aspergillus fumigatus conidia.

Adhesion of Aspergillus fumigatus, the causative agent of human aspergillosis, to the extracellular matrix protein laminin has been previously demonstrated. This study investigated the expression of laminin receptors during swelling of conidia, a step leading to germination and subsequent colonization of tissues. Scanning electron microscopy showed that the laminin binding sites were distributed over the external rodlet layer of resting conidia. During swelling, the characteristic rodlet layer progressively disintegrated and conidia surrounded by a smooth cell wall layer appeared. Flow cytometry using fluorescein isothiocyanate-conjugated laminin demonstrated that expression of laminin receptors at the surface of conidia was swelling dependent. Resting conidia expressed high levels of laminin receptors on their surface. A gradual decrease of laminin binding was then observed as swelling occurred, reaching a minimum for 4-h-swollen conidia. This correlated with a loss of adherence of swollen conidia to laminin immobilized on microtiter plates. Trypsin pretreatment of conidia reduced laminin binding. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and ligand blotting with laminin identified in a cell wall extract a major 72-kDa cell wall glycoprotein which binds laminin. Thus, one of the initial events in the host colonization may be the recognition of basement membrane laminin by this 72-kDa cell wall surface component.

Aspergillus fumigatus↗
PubMed1997

Sialic acid-dependent recognition of laminin and fibrinogen by Aspergillus fumigatus conidia.

In an attempt to define the molecular basis of the adherence of Aspergillus fumigatus conidia to the host tissues, a step which might be mediated by the recognition of basement membrane laminin or fibrinogen, we analyzed the binding of these glycoproteins by flow cytometry and a microtiter plate adherence assay. Flow cytometry revealed that the binding of fluorescein isothiocyanate-labeled laminin to conidia was saturable and specific. Moreover, the ability of conidia to bind laminin increased with their maturation. Competition experiments showed a cross-reactivity between laminin and fibrinogen binding and a lack of interactions with glycosaminoglycans. In addition, the binding of laminin was not inhibited by the different adhesive synthetic peptides tested. Furthermore, the microtiter plate assay of adherence to chymotrypsin degradation products of laminin or fibrinogen purified by gel filtration suggested a unique binding site common to sequential degradation fragments or the presence of multiple binding sites on the two ligands. Therefore, the role of carbohydrates in the recognition process was investigated. Among the carbohydrates tested, constitutive of the conidial wall or of the oligosaccharide side chains of laminin and fibrinogen, only N-acetylneuraminic acid and sialyllactose inhibited the binding of these glycoproteins to conidia. In conclusion, these results strengthen the idea that the laminin and fibrinogen receptors in A. fumigatus are identical and suggest an interaction mediated by a sialic acid-specific lectin of the conidial wall.

Aspergillus fumigatus↗
PubMed1996

A 33 kDa serine proteinase from Scedosporium apiospermum.

An extracellular proteinase produced by the filamentous fungus Scedosporium apiospermum has been purified and characterized. Initially, in vitro conditions for enzyme synthesis were investigated. The highest yield of enzyme production was obtained when the fungus was cultivated in modified Czapek-Dox liquid medium supplemented with 0.1% bacteriological peptone and 1% (w/v) glucose as the nitrogen and carbon sources respectively. Purification to homogeneity of the proteinase was accomplished by (NH4)2SO4 precipitation, followed by gel filtration through Sephadex G-75 and finally affinity chromatography through immobilized phenylalanine. Analysis of the purified enzyme by SDS/PAGE revealed a single polypeptide chain with an apparent molecular mass of 33 kDa. Further investigation of its physical and biochemical properties disclosed numerous similarities with those of the previously described serine proteinase of Aspergillus fumigatus. The enzyme was not glycosylated and its pI was 9.3. Proteinase activity was optimum between 37 and 50 degrees C and at pH 9.0, but remained high within a large range of pH values between 7 and 11. The inhibition profile and N-terminal amino acid sequencing confirmed that this enzyme belongs to the subtilisin family of serine proteinases. In agreement with this, the specific synthetic substrate N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide proved to be an excellent substrate for the proteinase with an estimated Km of 0.35 mM. Like the alkaline proteinase of A. fumigatus, this enzyme was able to degrade human fibrinogen, and thus may act as a mediator of the severe chronic bronchopulmonary inflammation from which cystic fibrosis patients suffer.

Amino Acid Sequence↗