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liberation of protoplasts from the yeast-like form of paracoccidioides brasiliensis by enzymatic treatment.spherical and osmotically sensitive protoplasts were released from cultures of the yeast-like form of paracoccidioides basilienisis strain ivic pb9 through the action of a mixture of crude enzyme preparations: alpha and beta-glucanases and chitinase, obtained from culture filtrates of cladosporium resinae, basidiomycete qm 806 and streptomyces sp respectively. the highest efficiency of protoplast liberation was achieved when each crude enzyme preparation was used at 1 mg/ml.1979531719
identification of yeast phase of pathogenic fungi by the specificity of their aminopeptidase(s).specificity of aminopeptidase(s) was fluorimetrically determined in the yeast phase of histoplasma capsulatum, h. duboisii, h. farciminosum, blastomyces dermatitidis, paracoccidioides brasiliensis, candida albicans and crytococcus neoformans. after individually incubating each of 26 amino acid-beta-naphthylamides with each yeast, the amount of each amino acid-beta-naphthylamide hydrolyzed was determined by measuring the free naphythylamine. this resulted in a reproducible profile of the aminopep ...1975808867
effect of cetylpyridinium chloride on pathogenic fungi and nocardia asteroides in sputum.the effect of cetylpyridinium chloride (cpc) on pathogenic fungi and nocardia asteroides was studied. sputa seeded with each of 11 organisms (aspergillus flavus; aspergillus fumigatus, blastomyces dermatitidis, candida albicans, coccidioides immitis, cryptococcus neoformans, geotrichum candidum, histoplasma capsulatum; nocardia asteroides, paracoccidioides brasiliensis, and sporothrix schenckii) were treated with cpc and kept for 2, 5 and 9 days. the cpc reagent used (0.5% cpc and 0.5% sodium ch ...1976773957
paracoccidioidomycosis (south american blastomycosis): treatment with miconazole.six patients with multisystem paracoccidioidomycosis proven by serology and culture or smear were treated with relatively brief courses of intravenous miconazole. two had relapsed following prior therapy; 6 had active pulmonary, 4 laryngeal, 2 oropharyngeal, 2 lymphoid, and 1 abdominal disease. paracoccidioides brasiliensis was highly susceptible to miconazole in vitro; minimal inhibitory concentration was less than or equal to 0.001 microgram/ml. clinical examination showed a prompt and objecti ...1978686247
effects of cyanein and ramihyphin a on the dimorphism of paracoccidioides brasiliensis.as a preliminary step in the study of dimorphism in paracoccidioides brasiliensis, the effects of cyanein and ramihyphin a were studied. these antibiotics have been reported to induce morphological changes in fungi. the results obtained suggest that ramihyphin a induce swelling of hyphae while partially inhibiting y leads to m transformation with the production of an incipient and swollen mycelium. cyanein did not affect the mycelial morphology as did ramihyphin a. however, the y leads to m tran ...1978669488
[tropic-subtropic fungus infections in germany].observations by the author and other workers on exotic mycoses in germany are used in order to establish several groups of patients. the following mycoses from tropical and subtropical areas and their causative agents are mentioned: tinea nigra (cladosporium werneckii), south american blastomycosis (paracoccidioides brasiliensis), coccidioidomycosis (coccidioides immitis), histoplasmosis (histoplasma capsulatum), mycetoma (madurella mycetomi), dermatophytosis/tinea capitis (trichophyton soudanen ...1978627480
[study of yeast phase histoplasma capsulatum antigens used for skin tests].the results of skin tests with two antigens of the yeast phase of histoplasma capsulatum are presented. both antigens were able to fix complement and form precipitating bands in the presence of sera from patients with active histoplasmosis. their sensitivity was lower than the metabolic antigen usually employed in serology. results of skin tests obtained with both yeast phase antigens and a standard histoplasmin coincided in animals infected with h. capsulatum. only one cross reaction was observ ...1979542887
a case of paracoccidioidal granuloma in norther nigeria.a case of paracoccidioidal granuloma in northern nigeria is presented. the fungus could be cultured and identified as paracoccidioides brasiliensis. histology revealed a fungal lesion due to a yeast like organism. the patient responded to long acting sulphormethoxine (fanasil). a variation from the classic histopathological description and association of pustular psoriasiform lesions on the soles with a possibility of 'id' reaction to the fungus are discussed.1979537129
experimental paracoccidioidomycosis in the syrian hamster: morphology, ultrastructure and correlation of lesions with presence of specific antigens and serum levels of antibodies.male hamsters (134) received intratesticular injection of a live cerebriform culture of paracoccidioides brasiliensis and were sacrificed from 6 hours up to 123 days onwards. tissues from testis, lymph nodes, lungs, liver, spleen, kidneys and intestines were examined microscopically; presence of specific antigens was saught in lesions of testis, regional lymph nodes and liver by indirect immunofluorescence (if); inoculation site lesions were studied electron microscopically and circulating speci ...1979481561
x-ray microanalysis as applied to fungal tissues.analytical electron microscopy combines the techniques of high-resolution electron microscopy and high-sensitivity x-ray microanalysis of samples. spectrometry of the elements (characteristic x-rays produced by a scanning electron microprobe) was employed to detect some elements of mendeleev's classification in pathogenic fungi for humans. x-ray microanalysis applied in wavelength dispersive spectrometry was used to study coccidioïdes immitis, paracoccidioïdes brasiliensis and trichosporum cutan ...1977558789
carboxylic activity of giant cells of human granuloma produced by paracoccidioides brasiliensis.the carboxilic activity of giant cells of human granuloma produced by p. brasiliensis was studied. the enzymatic activity was revealed by reddish-brown, purple red, and indigo-blue cytoplasmic precipitate, using the substrates alpha-naphthyl-acetate, naphthol-as acetate and 5-bromo-4-chloro-indoxyl acetate respectively. the giant cells were intensely positive in all cases studied. we believe this esterasic activity is related to the lytic, lisosomic activity of the macrophages and giant cells in ...19751224284
experimental paracoccidioidomycosis: cranial and nasal localization in mice.an experimental mouse model for paracoccidioidomycosis (south american blastomycosis) is described. when distribution of cranial lesions following i.v. injection was investigated, invasion of the nasal mucosa with subsequent discharge of budding paracoccidioides brasiliensis cells into the nasal cavity was noted. the possible significance of this finding in terms of the processes associated with naturally occurring paracoccidioidomycosis is discussed.1978708583
specific double diffusion microtechnique for the diagnosis of aspergillosis and paracoccidioidomycosis using monospecific antisera.using experimental reference sera against species-specific antigens of aspergillus fumigatus and paracoccidioides brasiliensis in a microdouble diffusion technique, a simple and specific test for the immunodiagnosis of aspergillosis and paracoccidioidomycosis has been developed. only sera that produced lines of identity with either one of the bands formed by the anti-c2 or the anti-e2 reference sera were considered positive for aspergillosis or paracoccidioidomycosis, respectively. the sensitivi ...1978416505
identification and purification of the specific antigen of paracoccidioides brasiliensis responsible for immunoelectrophoretic band e.a new purified antigen (e2) of paracoccidioides brasiliensis mycelial growth phase was isolated by immunoadsorption from a crude metabolic soluble extract of the fungus. the antiserum prepared in a rabbit by inoculation of e2 antigen developed only one immunodiffusion line with the crude metabolic extract. findings on immunological analysis showed that e2 antigen is the antigenic component of immunoelectrophoretic band e. the isolated antigens did not possess detectable alkaline phosphatase acti ...1977404719
histoplasma capsulatum: chemical variability of the yeast cell wall.four strains of histoplasma capsulatum were analyzed to observe any variations in their cell wall composition. strain g-184b produced the same amount of sugars reported by domer (2) although qualitative analyses agreed with kanetsuna's report (4) as far as the presence of glucose, galactose, and mannose was concerned. our results agree with previous reports in classifying h. capsulatum into chemotypes i and ii, the latter having more alpha-glucan in its cell wall. a decrease in the amount of fra ...1978752191
the use of fluorescein-labelled lectins in the detection and identification of fungi pathogenic for man: a preliminary study.fluorescein-labelled lectins of known specificities for different sugars were used in an attempt to identify fungi in paraffin sections of surgical and post-mortem material. aspergillus fumigatus, blastomyces dermatitidis, candida albicans, cryptococcus neoformans, paracoccidioides brasiliensis and rhizopus oryzae have been studied with five fluorescein-labelled lectins and with basis of differences in their reactions with these stains. the results accord well with what is known of the chemistry ...1978355633
[south american blastomycosis (paracoccidioidomycosis) in switzerland. clinical course and morphological findings in a case following long-term therapy].the clinical course and morphological findings are reported of visceral paracoccidioidomycosis or south american blastomycosis with lung involvement in a 47-year-old male after specific antimycotic treatment for 11 years. the patient had been infected during a stay in são paulo, brazil, from 1950 to 1954. the diagnosis was established in 1959 after his return to st. gall, switzerland, in tissue from buccal mucosa and cervical lymph node biopsy and in fungus cultures. the patient was treated with ...1979432600
the activation of the complement system by paracoccidioides brasiliensis in vitro: its opsonic effect and possible significance for an in vivo model of infection. 1979421371
[study of anti-paracoccidioides brasiliensis igm antibodies using immunofluorescence of the serum of patients with paracoccidioidomycosis]. 1979384494
cell wall analysis of an adenine-requiring mutant of the yeast-like form of paracoccidioides brasiliensis strain ivic pb9.an adenine-requiring mutant of paracoccidioides brasiliensis strain ivic pb9 was isolated after treatment of the yeast-like (y) form with nitrosoguanidine. cell wall analysis of this mutant (strain ivic pb141) showed an increase in the amount of alpha-1,3-glucan and a virtual disappearance of the antigenic galactomannan. at the same time, a higher degree of virulence was observed for the mutant. these results agree with the hypothesis presented before (16) about a relationship between cell wall ...1977601663
role of bats in the ecology of paracoccidioides brasiliensis: the survival of paracoccidioides brasiliensis in the intestinal tract of frugivorous bat, artibeus lituratus.the fruit-eating bat, artibeus lituratus, was fed known quantities of viable yeast cells and mycelial particles of paracoccidioides brasiliensis in an attempt to assess the role of this animal in the distribution of this agent in nature. results of mycosal cultures of the stomach, upper intestine, lower intestine and rectum clearly showed that the fungal cells were unable to survive more than 8 hours in the digestive tract of the bat. the mycelial particles were more susceptible than the yeast a ...1977601662
paracoccidioides brasiliensis: cell wall structure and virulence. a review.paracoccidioides brasiliensis is the causative agent of paracoccidioidomycosis or south american blastomycosis. many aspects of the disease and its agent are unknown. one of the most important factors regarding the infection and the host-parasite relationships seems to be the fungal cell wall whose biochemical aspects are reviewed here. biochemical studies, done mainly by kanetsuna et al., (21,22), have demonstrated that the yeastlike (y) and the mycelial (m) forms have chitin as a common polysa ...1977340954
blastomycosis of the colon resembling clinically ulcerative colitis.an 8 year old brazilian girl had an infection, apparently confined to the large intestine, with paracoccidioides brasiliensis. the symptoms were diarrhoea with fresh blood and mucus, severe malnutrition, and a spastic and ulcerated colon. she is making good progress on co-trimoxazole.1979533701
isolation and preliminary characterization of auxotrophic and morphological mutants of the yeastlike form of paracoccidioides brasiliensis.n-methyl-n'-nitro-n-nitrosoguanidine, which is known to be a very effective mutagen in many systems, was used to induce mutants in the yeastlike form of paracoccidioides brasiliensis strain ivic pb9, an imperfect fungus. forty-three auxotrophic and 27 prototrophic morphological mutants were isolated after treatment with 50 mug of nitrosoguanidine per ml in 0.1 m citrate buffer, ph 5.0. auxotrophic mutants required primarily either amino acids, purines, or pyrimidines. some auxotrophs were also m ...1977830638
host-parasite relationships in the yeastlike form of paracoccidioides brasiliensis strain ivic pb9.the yeastlike form of paracoccidioides brasiliensis strain ivic pb9 reduced the amount of alpha-1,3-glucan in its cell wall from 45 to 3% when subcultured in vitro for several years. this strain regained its alpha-1,3-glucan up to 25% of the total cell wall when grown in vivo. a mutant strain of p. brasiliensis pb9, named ivic pb140, reported to have 1,3-mannan instead of alpha-glucan in the cell wall, could not be recovered from experimentally infected animals. the existence of some relationshi ...1977844899
amino acid synthetic media for fungal pathogens based on aminopeptidase specificities: histoplasma capsulatum, blastomyces dermititidis, paracoccidioides brasiliensis and cryptococcus neoformans.the development of simple and chemically defined liquid media for histoplasma capsulatum, blastomyces dermatitidis, paracoccidioides brasiliensis and crypto-occus neoformans according to their aminopeptidases profiles as amino acid requirement was described. when 1.5% purified agar was added, these media also supported excellent mycelial growth and sporulation of the deep mycoses. h. capsulatum was converted to and maintained in yeast phase when 0.1% l-cystine was added to the solid medium incub ...19751099698
morphological conversion of 13 strains of three dimorphic fungi in tap and stream water.various strains of sporotrichum schenckii, histoplasma capsulatum and paracoccidioides brasiliensis show partial to complete (ca 70%) conversion to yeast when the mycelial culture is grown on sabouraud's dextrose agar at 25degreesc and palced in tap or stream water at 37degreesc. conversion (ca 70%) to mycelial phase occurs when the yeast culture is grown on brain heart infusion agar at 37degreesc and then placed in tap or stream water at 25degreesc. it was observed that, with the dimorphic orga ...19751242119
relationship between digestive and killing abilities of neutrophils against paracoccidioides brasiliensis.peripheral blood neutrophils (pmn) from patients with paracoccidioidomycosis killed and digested paracoccidioides brasiliensis much less than did pmn from normal individuals or from patients with other diseases. however, deficiency in killing ability was less specific than digestive deficiency and correlated poorly with it. we conclude that the capacities of pmn to digest and kill p. brasiliensis are not intimately related phenomena, and that in paracoccidioidomycosis the key deficiency of neutr ...19921302798
haematological alterations induced by biochemical fractions of paracoccidioides brasiliensis in mice.biochemical fractions of paracoccidioides brasiliensis were obtained for experimental inoculation in mice followed by haematological analysis. dead total fungus, total fungus disrupted by ultrasonic waves, lipids of the fungus, supernatant of the lipid purification, and integral and disrupted fungus free of lipids were obtained. the six fractions were obtained from lyophilized yeasts of a recent isolate of p. brasiliensis and from a pool comprising equal amounts of four strains maintained in the ...19921302799
a morphological mutant of paracoccidioides brasiliensis strain ivic pb9. isolation and wall characterization.a morphological mutant of paracoccidioides brasiliensis strain ivic pb9 was isolated after treatment of the yeast-like (y) form with nitrosoguanidine. colonies of the mutant grown at room temperature did not show the whitish cotton-like morphology typical of the mycelial form of the parental strain. y-cells were much smaller than those produced by the parent and grew forming chains of different sizes. the main chemical difference in the wall of the y-form was the replacement of the alpha-i,3-glu ...1976932675
growth curves of the yeast-like form of paracocidioides bradiliensis.growth curves of the yeast-like form of 4 strains of paracoccidioides brasiliensis based on colony counts on ggy agar and on cell counts weree made. mean generation times wer 17, 13 and 21 h. for 3 of the strains. the kinetics of growth for all strains showed that dead cells were present in approximately the same proportion as living cells in the initial inocula and their number increased through the exponential phase of growth at a similar rate as that of living cells. viability counts made in ...19751091997
cell-mediated immune responses in patients with paracoccidioidomycosis.we tested the hypothesis that symptomatic infection with paracoccidioides brasiliensis caused impaired host cellular immune responses. in a cross-sectional study in colombia, the immune responses of thirty-six patients with paracoccidioidomycosis were compared with those of sixty normal individuals. patients demonstrated increased skin sensitivity to paracoccidioidin (para) and histoplasmin, and reduced reactivity to candidin and dinitrochlorobenzene as compared to controls. the skin test respon ...1977862251
[preparation and study of a paracoccidioides antigen needed for skin tests].a cellular antigen from paracoccidioides brasiliensis, obtained from the supernate of the disrupted yeast phase, was studied. it was prepared by a method similar to that for obtaining the spherulin from coccidioides immitis. this antigen is composed of 55 mug/mg of polysaccharides, determined by the phenol method, and 7-8 mug/mg of protein, determined by folin-ciocalteu's technique. in vitro tests of antigenicity were done by immunodiffusion and complement fixation. the optimum dilution of the a ...1976996691
isolation of a specific antigen with alkaline phosphatase activity from soluble extracts of paracoccidioides brasiliensis.a specific antigen of paracoccidioides brasiliensis was isolated from a metabolic extract of the fungus. the extraction was made by specific adsorption to and subsequent elution from a column containing a cross linked polymer to which the antibodies of a monospecific rabbit serum had been covalently attached. the purity of the final product was demonstrated by immunodiffusion analysis of the eluate using immune serum produced in a sensitized rabbit. the purified antigen was shown to have cationi ...1976996692
new method for estimating digestion of paracoccidioides brasiliensis by phagocytic cells in vitro.we describe a method by which phagocytosis and digestion of paracoccidioides brasiliensis yeast cells by polymorphonuclear leukocytes or other phagocytic cells may be estimated. suspensions of p. brasiliensis in its yeastlike phase were sonicated, counted, and incubated with known numbers of peripheral blood polymorphonuclear leukocytes. at given intervals, cytocentrifuge droplets were stained by a variation of papanicolaou's method. stained preparations were examined with phase-contrast optics. ...197990683
[reactivity of a purified antigen of paracoccidioides brasiliensis with paracoccidioidomycosis and histoplasmosis sera].the immunoelectrophoretic reactivity of a "crude" and a "purified" antigens of paracoccidiodes brasiliensis against the sera of confirmed cases of paracoccidioidomycosis and histoplasmosis was evaluated. the "crude" antigen revealed precipitating antibodies in both the homologous and the heterologous human sera; the number of precipitating systems being higher with the former. the "purified" antigen reacted only with the homologous sera. it is postulated that the use of such "purified" antigen m ...197555090
comparative evaluation of a chemiluminescent dna probe and an exoantigen test for rapid identification of histoplasma capsulatum.a chemiluminescent dna probe (accuprobe) assay developed by gen probe, inc., for the rapid identification of histoplasma capsulatum was evaluated and compared with the exoantigen test by using 162 coded cultures including histoplasma capsulatum var. capsulatum, histoplasma capsulatum var. duboisii, histoplasma capsulatum var. farciminosum, blastomyces dermatitidis, coccidioides immitis, paracoccidioides brasiliensis, and morphologically related saprobic fungi. each test uses a chemiluminescent, ...19921452692
[study of serologic cross reactions between the antigens of paracoccidioides brasiliensis and histoplasma capsulatum].a comparative study of serologic cross-reactions between histoplasmosis and paracoccidioidomycosis was carried out using complement fixation (cf) and agar gel immunodiffusion (id) tests. sera from 77 patients with paracoccidioidomycosis, 38 with histoplasmosis and 50 healthy individuals were studied. the pan american health organization microtiter cf test and the hupper id technique were employed. the antigens were prepared by the method of ajello as modified by negroni. paracoccidioidin cf test ...197663979
lymphocyte subpopulations and cytokine production in paracoccidioidomycosis patients.despite the postulated role of the immune system in the control of the infection by paracoccidioides brasiliensis, only a few studies have addressed this point in patients. the determination of total lymphocytes and their subpopulations in 6 untreated patients with the chronic form of paracoccidiodomycosis showed that half of them were lymphopenic, because of low number of cd4+ t-lymphocytes. all patients had low cd4/cd8 ratios. on the contrary, b-lymphocytes were normal in all patients. an addi ...19911678489
induction of the synthesis of cell wall alpha-1,3-glucan in the yeastlike form of paracoccidioides brasiliensis strain ivic pb9 by fetal calf serum.in vitro subculturing of the yeastlike form of paracoccidioides brasiliensis strain ivic pb9 leads to the disappearance of alpha-1,3-glucan as a main component of its cell wall. however, the addition of fetal calf serum to the growth medium induces the synthesis of this polysaccharide. it is suggested that the synthesis of alpha-1,3-glucan in the cell wall of the yeastlike form of p. brasiliensis is induced by external factors.1977858645
immunohistologic diagnosis of systemic mycoses: an update.fluorescent antibody, immunoperoxidase and gold-silver staining methods for the rapid and accurate diagnosis of systemic mycotic infections are currently performed in a few specialized laboratories. these methods have proved applicable to formalin-fixed, paraffin-embedded tissues, and are reliable for identifying therein antigens of infectious dimorphic, monomorphic filamentous, and yeast-like fungal pathogens, i.e., aspergillus spp., blastomyces dermatitidis, candida spp., coccidioides immitis, ...19921397200
immunosuppressive effect of paracoccidioidomycosis sera on the proliferative response of normal mononuclear cells. identification of a paracoccidioides brasiliensis 34-kda polypeptide in circulating immune complexes.in this paper we relate that sera from paracoccidioidomycosis patients inhibited the mitogen-induced proliferative responses of normal mononuclear cells. treatment of these sera with 2.5% polyethyleneglycol (peg), a method classically used to precipitate immune complexes, significantly reduced their inhibitory activity. immunoblot analysis of the peg precipitates identified a 34-kda polypeptide, recognized by rabbit anti-p. brasiliensis igg. patient mononuclear cells showed partial restoration o ...19921435949
studies on the relationship between the estrous cycle of balb/c mice and their resistance to paracoccidioides brasiliensis infection.a relationship between the estrous cycle and non-specific host resistance to paracoccidiodes brasiliensis yeast cells was examined by using both sexes of adult balb/c mice. they were divided into 6 groups, including a male group and females at proestrus, estrus, metestrus-i, metestrus-ii and diestrus. the mice received yeast cells through three different inoculation routes; intravenous, intraperitoneal and intratracheal. in all of the inoculation routes, the clearance of the yeast cells was infl ...19921435956
[characterization of paracoccidioides brasiliensis antigens. serological immunodiagnosis using western blotting].the electrophoretic characterization on sds-page gels of paracoccidioides brasiliensis antigens, strains 2511 and 6688; and the additional use of immunoblotting has permitted in this study to identify the immunogenic, sensitive and specific antigen fractions for the diagnosis of paracoccidioidomycosis. the antigenic preparations showed differences depending on the morphologic form of the fungus and the method utilized. the procedure revealed heterogeneity in the humoral immune response of the pa ...19921343747
fate of conidia of paracoccidioides brasiliensis after ingestion by resident macrophages or cytokine-treated macrophages.conidia ingested by resident macrophages had an enhanced percentage of transformation to yeast cells compared with those in culture medium without macrophages. the yeast cells subsequently grew intracellularly by budding. macrophages treated with cytokines from antigen-stimulated spleen cells from immunized mice significantly inhibited transformation of ingested conidia.19921563800
beta-1-3-glucanase and dimorphism in paracoccidioides brasiliensis.mycelial and yeast forms of p. brasiliensis were tested for several glucohydrolases. in addition to high levels of beta-glucanases, low amounts of alpha-glucanase, chitinase and maltase were found. tests for invertase, amylase and lactase were negative. the levels of beta-1,3-glucanase were higher in the mycelial form. the shift to the mycelial phase correlated with an increase in the levels of beta-1,3-glucanase. the enzyme was present in the cytoplasm, cell wall and culture medium. the extrace ...197940530
[effect of phagocytosis in vitro on paracoccidioides brasiliensis].peripheral leukocytes from 17 patients with paracoccidioidomycosis were mixed with yeast cells from paracoccidioides brasiliensis and rhodotorula sp. to ascertain their phagocytic and lytic capacities. the role of circulating antibodies in the process was also investigated by the use of autologous serum. the phagocytic capacity of the leukocytes was found to be normal for both types of yeasts. however, in the presence of the patient's serum, the percentage of p. brasiliensis cells ingested was i ...19751168372
[paracoccidioides brasiliensis (lutz, 1908) isolated by hemoculture in a patient with the acquired immunodeficiency syndrome (aids)].a case of an aids patient with positive blood culture for paracoccidiodes brasiliensis is reported. the patient was a 29-years-old male born in nova londrina (paraná state, brazil) who presented splenomegaly and fever of unknown origin. three blood cultures were performed, each one of them for aerobic bacteria, mycobacteria and fungi. cultures for aerobic bacteria and mycobacteria were negative. however, the yeast phase p. brasiliensis was isolated from two cultures in bhi agar, 20 days after in ...19921342126
antigenemia in paracoccidioidomycosis.severe forms of paracoccidioidomycosis (pcm) are accompanied by intense immunological involvement characterized by depression of the cell-mediated immune response and by high levels of antibodies in serum with no protective function. these changes can be reversed by antifungal treatment. it has been suggested that antigens of paracoccidioides brasiliensis released into the circulation during the active phase of the disease may be involved in the genesis of the changes in the immune response. in ...19921537906
[gastric paracoccidioidomycosis. a case report and considerations on the pathogenesis of this disease].the authors report an unusual case of fungal gastric lesion in a patient with the chronic form of paracoccidioidomycosis. for a period of 8 months the major symptoms of the patient were abdominal pain and body weight loss. the endoscopic evaluation of the upper gastrointestinal tract showed a partial gastrectomy made previously, a great and irregular ulcer in the stomach and a granulated aspect of the duodenal mucosa. a granulomatous process and paracoccidioides brasiliensis were observed in the ...19921340750
activation of human complement system paracoccidioides brasiliensis and its deposition on the yeast form cell surface.the yeast form of paracoccidioides brasiliensis strain pb18 was able to activate c3 of normal human serum diluted in phosphate-buffered saline or egta-mgcl2 in vitro. c3 convertase was also permissive when pb18 cells were pre-treated with a pool of immune serum from patients with paracoccidioidomycosis and incubated in serum diluted in edta-cacl2. the components c3, and fragments c3c, c3d, c3g, factor h, factor b, c4 and c5b-9 were demonstrated on the pb18 cell surface by immunofluorescence alth ...19921287168
antigens of diagnostic value in three isolates of paracoccidioides brasiliensis.yeast cellular extracts of three isolates of paracoccidioides brasiliensis were tested by the western-blot technique against 53 sera from patients with paracoccidioidomycosis (pcm). numerous antigens were recognized by the sera but only five were specific for (58, 57, 48, 44 and 23 kda). these specific antigens had the same relative molecular mass in the different isolates but their reactivity with sera from pcm patients was variable. an antigen in isolate 688, which was specific for pcm, had an ...19911719178
biochemical analysis of the methylic antigen of paracoccidioides brasiliensis.yeast forms of five strains of paracoccidioides brasiliensis (sn, 2, 18, 192 and jt-1) were cultured in a synthetic medium for obtaining methylic antigens. these antigens were lyophilized and studied for each strain, to determine their partial biochemical composition, through measurements of total lipid, protein and carbohydrate contents. lipids of methylic antigens were purified and analysed for sterols, phospholipids, glycolipids, lipoproteins, and partial characterization of sterols. signific ...19921342119
specific recognition pattern of igm and igg antibodies produced in the course of experimental paracoccidioidomycosis.specific igm and igg responses to paracoccidioides brasiliensis produced in resistant and susceptible mice during experimental paracoccidioidomycosis were examined by the immunoblotting procedure. sera from infected mice recognized 51 antigen bands with apparent molecular masses from 8 to 86 kd. sixteen of these were defined as major antigen bands because of almost universal presence of antibodies to them, and their intense staining. all sera, including those from normal control mice, tested for ...19921563097
the source of the growth-promoting factor(s) affects the plating efficiency of paracoccidioides brasiliensis.we studied the influence of the growth factor (gf) source, concentration and production time on the plating efficiency of paracoccidioides brasiliensis yeast cells. the highest plating efficiencies were achieved when the gf was derived from a fast growing p. brasiliensis isolate which was not homologous to the plated samples.19921517962
studies on the relationship between paracoccidioidomycosis in ddy mice and their estrous cycle.the relationship between paracoccidioidomycosis in ddy mouse and its estrous cycle was studied. adult ddy mice of both sexes were used as experimental animals. estrous cycle of female mice was examined before inoculation of paracoccidioides brasiliensis yeast cells and mice were divided into 5 groups such as proestrus, estrus, metestrus-i, metestrus-ii and diestrus. each mouse was inoculated intravenously with 10(6) p. brasiliensis yeast cell units and sacrificed on day 28 after inoculation. the ...19911784309
development of pulmonary fibrosis in mice during infection with paracoccidioides brasiliensis conidia.pulmonary fibrosis is a feared sequelae of paracoccidioidomycosis. we sought to determine if mice exposed to paracoccidioides brasiliensis conidia would develop pulmonary fibrosis. balb/c mice were infected intranasally with p. brasiliensis conidia and sacrificed at regular intervals. one lung was sectioned for histopathology and sections were stained with haematoxylin and eosin, trichromic and argentic stains; the other lung was homogenized and cultured to determine the viability of the fungus. ...19921517956
studies on the relationship between the pathogenicity of paracoccidioides brasiliensis in mice and its growth rate under different oxygen atmospheres.we performed comparative studies of the pathogenicity of six strains of paracoccidioides brasiliensis (bt-9, bt-4, pb-9, pb-18, bt-7 and b-1183) for young adult male ddy mice and the growth rate of each strain under different oxygen atmospheres (aerobic, micro-aerobic and anaerobic atmospheres) at 37 degrees c. 10(6) units of yeast cells were intravenously injected into each mouse. the pathogenicity of each isolate was determined by a scoring system based on organ culture and histopathological f ...19911831538
transfer of cell-mediated immunity to paracoccidioides brasiliensis in hamsters with dialysable leukocyte extracts.dialysable leukocyte extracts (dle) were obtained from lymph nodes and spleen cells of hamsters immunized with paracoccidioides brasiliensis (immune dle) or from non-immunized hamsters (non-immune dle). sensitivity to p. brasiliensis antigen (pbag) was transferred by immune dle to normal recipient hamsters and could be detected by the macrophage migration inhibition (mif) assay on day three and by a positive skin test to pbag on day seven after dle inoculation. this reactivity persisted for 120 ...19901694543
mutants of paracoccidioides brasiliensis strain ivic pb9 affected in dimorphism.morphological mutants were isolated after nitrosoguanidine treatment of paracoccidioides brasiliensis strain ivic pb9. two of these mutants, pb257 and pb258, developed a typical mycelia at 23 degrees c, however, the yeast cells which developed at 37 degrees c were indistinguishable from those of the parental strain. a third mutant, strain pb267, was thermosensitive, grew as yeast-like cells at 23 degrees c, but was unable to survive at 37 degrees c. morphological observations as well as serologi ...19921573521
serologic characterization of paracoccidioides brasiliensis e2 antigen.1. the behavior of the specific e2 antigen of paracoccidioides brasiliensis was studied by agarose gel counterimmunoelectrophoresis. when the gel was read immediately after the electrophoretic run no precipitation band was visible. visualization of the complex was possible only after incubation of the gel at room temperature overnight. 2. at alkaline ph, the e2 antigen migrates in the direction of the cathode, as do the immunoglobulins. the higher sensitivity of counterimmunoelectrophoresis when ...19911724622
sensitive immunoradiometric assay for the detection of paracoccidioides brasiliensis antigens in human sera.in the present study we report the standardization of an immunoradiometric assay (irma) for detection of paracoccidioides brasiliensis circulating antigens that could be useful in the diagnosis and prognosis of paracoccidioidomycosis. for this purpose we studied the reactivities of p. brasiliensis and other mycotic antigens with rabbit polyclonal anti-p. brasiliensis antibodies (immunoglobulin g) in order to evaluate the sensitivity and specificity of an irma for detecting p. brasiliensis antige ...19911907608
[utilization of aminoacids in the study of the growth of paracoccidioides brasiliensis. influence on dimorphism].fifteen paracoccidioides brasiliensis strains, in the mycelial (m) and yeast like (y), were cultivated in minimal medium (mm) and subcultivated to be adapted to the same medium supplemented with a pool of amino acid in solution (mms). each of the amino acids were studied separately of the solution to provide the auxological study. the prototrophism was demonstrated by nine strains in both m and y forms, and the auxotrophism by the remaining strains. the heterologous results has not allowed us to ...19911844955
in vitro action of some disinfectants on paracoccidioides brasiliensis yeast forms.the fungicidal action of sodium hypochlorite (0.3, 1, 2.5, 5 and 10%); formaldehyde (2, 5, and 10%); and ethyl alcohol (70%) on yeast forms of paracoccidioides brasiliensis pb 18 and a newly-isolated goiana strain was described. contact between the fungus and the disinfectants was maintained for 1, 2, 24, 48 and 72 hours at room temperature. viability was evaluated by the fluorescein diacetate-ethidium bromide treatment, culture in solid and liquid media (36 degrees c and 26 degrees c); yeast to ...19911843395
the sensitivity, specificity and efficiency values of some serological tests used in the diagnosis of paracoccidioidomycosis.this work reports on the results of double immunodiffusion (id), counterimmunoelectrophoresis (cie), complement fixation (cf) and indirect immunofluorescence (iif) techniques in the serodiagnosis of paracoccidioidomycosis. the study was undertaken on four groups of individuals: 46 patients with untreated paracoccidioidomycosis, 22 patients with other deep mycoses, 30 with other infectious diseases (tuberculosis and cutaneous leishmaniasis) and 47 blood donors as negative controls. data were obta ...19911844949
isolation and antigenicity of a 45-kilodalton paracoccidioides brasiliensis immunodominant antigen.in the present study, we analyzed human antibody responses to paracoccidioides brasiliensis cellular antigens by the immunoblot technique to identify specific cellular components and to investigate the existence of antigen profile differences among serological responses of paracoccidioidomycosis (pcm) patients. among the 64 pcm serum samples analyzed, a relatively homogeneous immunoglobulin g response to p. brasiliensis antigens was observed. the polypeptide with a mass of 45 kda was the most cl ...19921612736
[biochemical regulations in the dimorphism and virulence of pathogenic fungi for humans].some biochemical mechanisms involved in the processes of virulence and dimorphism in fungi pathogenic for humans are reviewed. among them, the participation of sulphydryl and disulfide groups, hormone receptors and intra- and extracellular proteinases in histoplasma capsulatum, paracoccidioides brasiliensis and coccidioides immitis.19921338937
scanning electron microscopy of the conidia produced by the mycelial form of paracoccidioides brasiliensis.the conidia produced by the mycelial form of paracoccidioides brasiliensis were examined by scanning electron microscopy for the first time. several different conidial types were characterized. these included intercalary arthroconidia, several types of septate conidia that are formed from other conidia, pedunculate conidia, and terminal hyphal conidia. in addition, the ultrastructure of the supporting pedestal of the pedunculate conidium was found to be separated from the mother conidium by a se ...19911857400
reticulin antibodies: relationship with endocardium-vessel-interstitium antibodies and heterophilic antibodies.1. indirect immunofluorescence was used to compare reticulin antibodies, endocardium-vessel-interstitium (evi) antibodies and heterophilic antibodies in serum samples from patients with degenerative and inflammatory diseases, chagas' disease, or paracoccidioidomycosis and from healthy blood donors. 2. the antigen substrates used were rat, mouse and human liver for reticulin antibodies, mouse and human heart and skeletal muscle for evi factor, and rat heart and rat, mouse and human kidney and sto ...19902119837
proteolytic activity of the 43,000 molecular weight antigen secreted by paracoccidioides brasiliensis. 19902135482
killing of paracoccidioides brasiliensis conidia by pulmonary macrophages and the effect of cytokines.the ability of conidia, the infectious form of the dimorphic fungus paracoccidioides brasiliensis, to be killed in vitro by murine pulmonary macrophages was studied. mice were immunized by intravenous injection of killed conidia, which resulted in cellular immunity demonstrated by delayed type hypersensitivity in vivo and macrophage migration inhibition factor production in vitro. resident pulmonary macrophages from non-immune mice were able to significantly kill the conidia (28%). such macropha ...19921588466
43-kilodalton glycoprotein from paracoccidioides brasiliensis: immunochemical reactions with sera from patients with paracoccidioidomycosis, histoplasmosis, or jorge lobo's disease.sera from patients with paracoccidioidomycosis (pcm), histoplasmosis (hp), or jorge lobo's disease (jl) were titrated against purified gp43 from paracoccidioides brasiliensis by using both enzyme-linked immunosorbent assay (elisa) and immunoprecipitation (ipp) reactions with 125i-labeled antigens. in ipp, pcm sera and other sera could be distinguished on the basis of serum titers, whereas in elisa, 53% of the hp sera and 29% of the jl sera reacted similarly to the pcm sera. to investigate the po ...19911722220
[the use of exoantigens for identifying histoplasma capsulatum].the exoantigen test has been successfully used in the last years for the immunological identification of pathogenic fungi. twenty seven straing presumptively identified as histoplasma capsulatum by morphologic methods, were studied by such test. the exoantigens obtained from each strain were studied by immunoprecipitation technique in front of histoplasmosis control sera experimentally obtained in rabbits. reference strains of histoplasma capsulatum. histoplasma duboisii and paracoccidioides bra ...19902089510
the 43-kda glycoprotein from the human pathogen paracoccidioides brasiliensis and its deglycosylated form: excretion and susceptibility to proteolysis.biochemical properties of the concanavalin a-binding 43-kda glycoprotein (gp43) of paracoccidioides brasiliensis and its deglycosylated form were compared. deglycosylation was achieved by treatment with trifluoromethanesulfonic acid, endoglycosidase h, n-glycanase, or metabolically, by growing cells with tunicamycin. the resulting antigen in all cases had mr 38,000, and probably derived from the gp43 by loss of n-linked high-mannose oligosaccharide chains. the presence of galactopyranose units i ...19911898073
experimental paracoccidioidomycosis in ethyl alcohol-fed rats.1. the course of experimental paracoccidioidomycosis was studied in alcohol-fed rats and compared with pair-fed and ad libitum controls. the alcohol-fed rats were fed a regular commercial solid diet plus a 32% (v/v) ethyl alcohol-25% sucrose (w/v) solution 4 weeks prior to the infection and throughout the study. the inoculum was standardized in terms of virulence, age of culture, percentage of multicellular fungal units containing 1-3 cells and viability. 2. the extent of infection was measured ...19911797283
kinetics and requirements for activation of macrophages for fungicidal activity: effect of protein synthesis inhibitors and immunosuppressants on activation and fungicidal mechanism.peritoneal-and pulmonary macrophages can be activated in vitro with lymphokines (lk) or ifn-gamma, without exogenous lipopolysaccharide, for fungicidal activity against several pathogenic fungi. however, neither the biochemical nor metabolic events of the activation process or of the effector phase have been defined. in the present work we sought to elucidate these events with time-course studies using inhibitors of protein synthesis as well as immunosuppressive agents. we found that protein syn ...19911712253
alterations in the pathogenicity of one paracoccidioides brasiliensis isolate do not correlative with its in vitro growth.the in vitro subcultivation of some microorganisms for long periods causes measurable loss of their pathogenicity, which can be reverted by reisolation from infected hosts. we compared the pathogenicity and the in vitro growth pattern of one p. brasiliensis isolate (pb 18) in its yeast phase, using the following samples: 1) the original pathogenic pb 18 (op). 2) pb 18 attenuated by continuous in vitro subcultivation (at). 3) pb 18 (at) reisolated from susceptible b10.a mice (rs). 4) pb 18 (at) r ...19902233986
the use of cell-free antigens of paracoccidioides brasiliensis in serological tests.a simple and rapid method for extracting specific cell-free antigens (cfa) from the yeast form of paracoccidioides brasiliensis grown on agar slants was developed. extracts were analysed mainly by immunodiffusion (id) tests, for the immunodiagnosis of paracoccidioidomycosis. extracts were obtained from 2 to 7-day-old cultures. the extract obtained after the third day, which contained 200-300 micrograms of protein/ml, gave the best id reactions, with 100% sensitivity and specificity. the main pre ...19911905751
lobomycosis as a disease of the atlantic bottle-nosed dolphin (tursiops truncatus montagu, 1821).skin lesions on an atlantic bottlenosed dolphin, captured off the coast of florida, were investigated and found to be histologically and microbiologically indistinguishable from those caused in humans by loboa loboi. all attempts to isolate the etiologic agent or to transmit the infection to mice and monkeys ended in failure. sight records of other suspected dolphin cases of lobomycosis in florida waters are described along with citations of two previously confirmed and published dolphin infecti ...19751111350
sputum cytology in the diagnosis of pulmonary paracoccidioidomycosis.the presence of paracoccidioides brasiliensis was determined in sputum samples from 50 patients with paracoccidioidomycosis using four different techniques: (a) cell-block preparations stained with silver methenamine, (b) direct microbiologic examination, (c) smears stained with shorr, and (d) smears stained with silver methenamine. overall, cell-block preparations and smears stained with silver methenamine proved to be the most sensitive techniques, followed by smears stained with shorr and dir ...19911886644
purification of the 43 kda glycoprotein from exocellular components excreted by paracoccidioides brasiliensis in liquid culture (tom medium).the 43 kda glycoprotein (gp43) antigen has been purified by affinity chromatography and sephacryl s-200 gel filtration from concentrated and dialysed culture supernatant fluids of paracoccidioides brasiliensis grown in a tomato juice-enriched complex medium (tom). in the tom medium, there was rapid and extensive growth of the fungus, with an abundant production of gp43 in relation to other exocellularly accumulated components. the purified gp43 can be used for immunochemical and structure determ ...19912061796
a novel method for estimating killing ability and digestion of paracoccidioides brasiliensis by phagocytic cells in vitro.we describe a novel method by which phagocytosis, digestion and killing of paracoccidioides brasiliensis yeast cells by polymorphonuclear leukocytes or other phagocytic cells may be estimated simultaneously. suspensions of p. brasiliensis (yeast-like phase) were sonicated, counted and incubated at 37 degrees c with known numbers of phagocytes. control preparations contained no phagocytic cells. at given intervals samples were incorporated into gelatin nutrient medium and droplets of the mixtures ...19852413556
study of antibodies in paracoccidioidomycosis: follow-up of patients during and after treatment.the relevance of the humoral response in the prognosis of paracoccidioidomycosis was assessed by measuring the serological responses of individual patients to paracoccidioides brasiliensis by double immunodiffusion (did). sixty-six patients with paracoccidiodomycosis were studied. sera from 31 individuals were tested before and during treatment with sulfonamide (group i). sera from a further 35 individuals were tested after completion of a 2-year course of treatment (group ii). in group i, clini ...19902116515
the use of a mixture of somatic and culture filtrate antigens in the evaluation of the immune response to paracoccidioides brasiliensis.three paracoccidioides brasiliensis antigens, namely a culture filtrate preparation, a somatic antigen and a mixture of equal parts of the two, were tested by two serological techniques against sera from patients with paracoccidioidomycosis, and in an in vivo delayed hypersensitivity model in mice. the antigen mixture was more sensitive than the two individual antigens for the evaluation of the humoral and cellular immune response to p. brasiliensis, both in man and in experimental animals.19911955953
electron microscopic study of conidia produced by the mycelium of paracoccidioides brasiliensis.the ultrastructure of asexual spores (conidia) produced by the mycelial form of paracoccidioides brasiliensis was studied for the first time with transmission electron microscopy, using thin sections of aldehyde-osmium-fixed and epoxy-resin-embedded samples. the various types of conidia observed in the sections correlated well with previous light-microscopic descriptions. these types were intercalary or apical conidia, depending on their location along the originating hyphae. as in previous stud ...19911886643
efficiency of crude and purified fungal antigens in serodiagnosis to discriminate mycotic from other respiratory diseases.mycotic immunodiagnosis was performed in 186 hospitalized patients with different respiratory diseases, mostly considered as tuberculosis and others with a doubtful diagnosis. crude histoplasmin, coccidioidin, paracoccidioidin, blastomycin, candidin, aspergillin, and sporotrichin, as well as purified polysaccharide-protein complexes (ppc) of histoplasma capsulatum, coccidioides immitis, and paracoccidioides brasiliensis were used as antigens. immune tests used included skin test (st), gel immuno ...19911749392
hypersensitivity pneumonitis to paracoccidioides brasiliensis antigens in mice.hypersensitivity pneumonitis was induced in mice immunized with paracoccidioides brasiliensis and challenged, one week later, with soluble (spbag) or particulate (ppbag) antigen (formalin-killed yeast cells), administered by the intratracheal route. between 24 and 48 h post-challenge, animals developed an interstitial and intra-alveolar pneumonitis. macrophages and lymphocytes arranged focally into loose or mature granulomata were observed by light and electron microscopy. the distribution and f ...19892501469
in situ localization of t lymphocyte subsets in human paracoccidioidomycosis.immunohistochemical techniques using monoclonal antibodies to t lymphocyte subsets were used to characterize granulomas caused by paracoccidioides brasiliensis. punch biopsies of skin or mucosa from eight patients and of lymph nodes from two patients with disseminated paracoccidioidomycosis were studied. the t lymphocytes were distributed either in a localized pattern related to epithelioid granulomas or in a diffuse arrangement, predominantly around the vessels. in the granulomas, t cells forme ...19892528613
intrinsic vascularization of granuloma in experimental paracoccidioidomycosis.rats infected with paracoccidioides brasiliensis exhibited vascularized granulomas during the granulomatous stage, with more intensity on the 49th day after infection. these data change the classical belief that the granuloma is always an avascular structure. the authors suggest that the granuloma is under the balanced influence of angiogenic or angiostatic factors, with the usual predominance of the latter, with the consequent advantage of limited antigen diffusion to the vascular system.19882470450
influence of serum on in vitro digestion of paracoccidioides brasiliensis by neutrophils.serum from patients with paracoccidioidomycosis (para) did not block digestive abilities of neutrophils (pmns) from healthy individuals against paracoccidioides brasiliensis. conversely, serum from healthy donors did not enhance digestive capacities of pmns from patients with para vis á vis the causative organism. we conclude that the specific digestive defect present in pmns from patients with para is not mediated by serum factors.19902359415
ultrastructure of phagocytosed paracoccidioides brasiliensis in nonactivated or activated macrophages.transmission electron microscopy was used to study ultrastructures in paracoccidioides brasiliensis yeast cells after ingestion by nonactivated or cytokine-activated murine peritoneal macrophages. yeast cells ingested by nonactivated macrophages had typical bi- and trilayered cell walls, plasma membranes, mitochondria, nuclei, vacuoles, etc., which remained intact for 24 h of coculture. in contrast, yeast cells ingested by activated macrophages exhibited abnormal mitochondrial ultrastructures wi ...19902370112
antigenic structure of paracoccidioides brasiliensis. 19892490077
fluconazole: a new triazole antifungal agent.fluconazole is a fluorine-substituted, bis-triazole antifungal agent. its mechanism of action, like that of other azoles, involves interruption of the conversion of lanosterol to ergosterol via binding to fungal cytochrome p-450 and subsequent disruption of fungal membranes. activity against aspergillus spp., blastomyces dermatitidis, candida spp., coccidioides immitis, cryptococcus neoformans, histoplasma capsulatum, and paracoccidioides brasiliensis has been demonstrated in several animal mode ...19902260347
characterization of the cellular antigens of paracoccidioides brasiliensis yeast form.antigenic components of the yeast extract of paracoccidioides brasiliensis linder 2511 cultured for 3, 8, 20, 30, and 60 days were examined by the western blot (immunoblot) technique. the 3-day extract was chosen for characterization of the antigenic components because its stability did not vary with time and it contained all antigens identified by patient sera. antibodies to cross-reacting antigens of p. brasiliensis extracts were detected in sera from patients with histoplasmosis, candidiasis, ...19902380351
[glucan synthetase in paracoccidioides brasiliensis]. 19902152347
preparation of species-specific murine monoclonal antibodies against the yeast phase of paracoccidioides brasiliensis.a panel of four murine monoclonal antibodies showing species specificity for the yeast phase of the pathogenic dimorphic fungus paracoccidioides brasiliensis was produced by using a modification of the standard monoclonal antibody technology. this involved the use of the immunosuppressive drug cyclophosphamide to suppress the immune response of test animals to fungi showing cross-reactivity, i.e., to histoplasma capsulatum. one monoclonal antibody, p4, which had a high titer by enzyme-linked imm ...19902394802
preparation and use of cytoplasmic antigens for the serodiagnosis of paracoccidioidomycosis.a cytoplasmic antigen of paracoccidioides brasiliensis (strain mtc) prepared from the yeast phase grown in the chemically defined medium of mcveigh and morton is described. this antigen can be easily prepared, does not vary from lot to lot, and can be lyophilized without loss of activity or potency. in the immunodiffusion test, the cytoplasmic antigen demonstrated a sensitivity of 97% and a specificity of 100% when tested against 218 sera from 139 cases of paracoccidioidomycosis. when 177 sera f ...19852410446
antibody response to the 43 kda glycoprotein of paracoccidioides brasiliensis as a marker for the evaluation of patients under treatment.sera of patients with paracoccidioidomycosis contained igg-, iga-, and igm-specific antibodies to a 43 kda antigen contained in the filtrate of a culture of paracoccidioides brasiliensis. igg- and iga-specific antibodies were present in all observed patients. the igm response was more frequent in acute cases, and the mean titers of igg- and igm-specific antibodies were higher in the acute forms. by the fourth month of chemotherapy, there was a decay of igg, iga, and igm antibody titers to this a ...19902389824
dimorphism in histoplasma capsulatum: a model for the study of cell differentiation in pathogenic fungi.several fungi can assume either a filamentous or a unicellular morphology in response to changes in environmental conditions. this process, known as dimorphism, is a characteristic of several pathogenic fungi, e.g., histoplasma capsulatum, blastomyces dermatitidis, and paracoccidioides brasiliensis, and appears to be directly related to adaptation from a saprobic to a parasitic existence. h. capsulatum is the most extensively studied of the dimorphic fungi, with a parasitic phase consisting of y ...19892666842
[paracoccidioidomycosis and infection by the human immunodeficiency virus].we present two cases of paracoccidioidomycosis, one occurring in an aids patient and the other in an hiv infected man. this is the first report of such association. the first patient, which was already followed for hiv infection (group iv-a) presented with high fever and hepatosplenomegaly. plain x-ray, ultrasound and ct-scan of the abdomen showed solid nodules in the spleen, some of them with calcification. both the direct smear and the culture of a bone marrow aspiration revealed paracoccidioi ...19892690307
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