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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
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
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
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
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
[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
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
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
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
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
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
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
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
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
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
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
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
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
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 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
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
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
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
[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
[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
[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
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
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
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
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
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
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
[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
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
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
combined histochemical stains in the differential diagnosis of cryptococcus neoformans.three combinations of histochemical stains were used to study 69 routinely processed tissues containing various "yeast-like" fungal organisms (cryptococcus neoformans, blastomyces dermatitidis, coccidioides immitis, histoplasma capsulatum, paracoccidioides brasiliensis, and candida albicans). fontana-masson stain combined either with mucicarmine or alcian blue produced distinctive staining of c. neoformans (fontana-masson-positive wall and mucin-positive capsule) that was not identified in other ...19937678937
a comparative study of four different staining methods for estimation of live yeast form cells of paracoccidioides brasiliensis.a comparative study of four different staining methods for estimation of live yeast form cells of paracoccidioides brasiliensis was carried out. the staining methods used were fluorescent staining, vital dye exclusion tests with erythrosin b and by janus green and lactophenol cotton blue staining. colony forming units (cfu) of the yeast form of eight p. brasiliensis isolates on brain heart infusion agar (bhia) supplemented with 4% horse serum plus 5% p. brasiliensis cell extract (bhia + hs + ext ...19937517514
the causative agent of jorge lobo's disease, the fungus p. loboi (= loboa loboi) may be seen extracellularly tightly encircled by histiocytes. observations at the transmission and scanning electron microscopes. 19938278764
an improved culture medium for detecting live yeast phase cells of paracoccidioides brasiliensis.the plating efficiency of standard mycological media such as brain heart infusion (bhi) agar is poor for paracoccidioides brasiliensis. we prepared a water-extract of yeast phase cells of p. brasiliensis and examined it for growth-enhancing activity for the fungus. the water-extract, when added to bhi agar to a concentration of 5%, improved the plating efficiency of the medium for the fungus to some extent, but the degree of improvement was considerably varied among p. brasiliensis isolates. by ...19938360811
placental involvement in paracoccidioidomycosis.a case of juvenile-type paracoccidioidomycosis in a pregnant woman is reported. the disease pre-dated pregnancy and antifungal treatment was being administered when she became pregnant. a premature male infant was delivered with no evidence of infection. microscopic examination of the placenta showed numerous paracoccidioides brasiliensis yeast forms in the intervillous space, enmeshed in a macrophagic-phagocytic reaction, with damage of the trophoblastic layer. placental transfer of specific p. ...19938360816
recovery of adrenal function after treatment of paracoccidioidomycosis.in endemic areas, the systemic mycosis paracoccidioidomycosis (pcm) is the most frequent etiology of addison's disease. paracoccidioides brasiliensis, the causative agent of pcm, exhibits a high tropism for the adrenal glands, which results in a low hormone reserve and in more severe cases, in symptoms of primary adrenal insufficiency. in these cases, the hormone deficit is usually treated with replacement corticoid therapy for the rest of the patient's life. recently, we identified three patien ...19938390794
effect of anti-il-4, interferon-gamma and an antifungal triazole (sch 42427) in paracoccidioidomycosis: correlation of ige levels with outcome.paracoccidioidomycosis is characterized by depressed cellular but enhanced humoral immune responses, which suggests a th2 type of response to infection. we investigated possible therapeutic roles for anti-il-4, interferon-gamma (ifn-gamma) and/or sch 42427 (sch), a new triazole antifungal agent, and their effect on serum ige levels in a murine model of chronic paracoccidioides brasiliensis infection. balb/c mice infected by the pulmonary route were studied with three programmes. the subacute mod ...19938403491
experimental murine paracoccidioidomycosis: relationship among the dissemination of the infection, humoral and cellular immune responses.the dissemination of paracoccidioides brasiliensis cells to the heart, omentum/pancreas, spleen, liver and lungs, assessed by colony forming unit (cfu) counts, the levels of specific antibodies to this fungal agent (by elisa), and the specific dth reaction were studied in susceptible (b10.a) and resistant (a/sn) mice. the animals were infected intraperitoneally with p. brasiliensis yeast cells and were evaluated 2, 4, 12 and 16 weeks later. the most remarkable differences between the two mouse s ...19938403521
biochemical and physiological aspects in the dimorphism of paracoccidioides brasiliensis.paracoccidioides brasiliensis is a dimorphic fungus pathogenic for humans. it shows a yeast like phase at 37 degrees c and a mycelial phase at 23 degrees c. biochemical aspects of its dimorphism are related to the presence of hormone receptors, regulation of camp, or modulation of glucan synthetase activity through cytoplasmic proteinases. these aspects are reviewed herein.19938298276
two-dimensional immunoelectrophoresis of histoplasmin and a purified polysaccharide-protein antigen of histoplasma capsulatum.crude histoplasmin and a polysaccharide-protein complex (ppc-histo) antigens obtained from culture filtrates of histoplasma capsulatum were analyzed by single and tandem two-dimensional immunoelectrophoresis (td-iep) using a rabbit hyperimmune anti-histoplasmin polyvalent serum. single td-iep showed 14 arc precipitates for histoplasmin. continuity of arcs 2, 6, and 7, and 9 and 10 was observed, suggesting a different polymeric configuration of the same antigen. this was also confirmed in tandem ...19938326996
[comparative study of the pathogenicity and antigenicity of 6 paracoccidioides brasiliensis strains].a comparative study of antigenicity and pathogenicity for rats of six paracoccidioides brasiliensis strains was carried out. the antigenic capacity "in vitro" of cytoplasmic extract from each strain was determined by immunodiffusion test against 6 serum samples obtained from rats experimentally infected with paracoccidioides brasiliensis, that had presented positive reactions with a metabolic control antigen. the cytoplasmic extracts were used at final concentration of 100 mg/ml. all of them sho ...19937997758
tumour necrosis factor production in vivo and in vitro in response to paracoccidioides brasiliensis and the cell wall fractions thereof.tumour necrosis factor (tnf) was detected in serum from mice challenged with paracoccidioides brasiliensis. the serum tnf levels of mice challenged with an avirulent strain were significantly higher than those of mice challenged with a virulent strain, and the same was observed for the tnf levels of mice challenged with a cell wall fraction (f1) from the two fungal strains. fraction f1 consisted of chitin and beta-glucan; but although the chitin contents were similar for the two strains, the avi ...19938348743
factors associated with paracoccidiodes brasiliensis infection among permanent residents of three endemic areas in colombia.the natural habitat of paracoccidioides brasiliensis, the aetiologic agent of paracoccidioidomycosis, has not been determined. consequently, the events leading to the acquisition of infection remain controversial. to identify factors associated with infection in endemic areas we conducted a survey in three rural communities in colombia where we had previously diagnosed paracoccidioidomycosis in children. permanent residents were surveyed taking into consideration environmental and occupational v ...19938348926
effect of ajoene on dimorphism of paracoccidioides brasiliensis.ajoene, a compound derived from ethanolic garlic extracts, inhibits the growth of the dimorphic pathogenic fungus paracoccidioides brasiliensis, yeast cells being more sensitive to its action than mycelial cultures. sulphydryl protector groups were able to cancel the inhibitory effect on the yeast cells but not on the mycelial cultures. the dimorphic process was also blocked when mycelia were placed to transform to yeast. synthesis in vitro of cell wall glucan was not affected by ajoene. we disc ...19938509950
specific digestive deficiency of phagocytes in paracoccidioidomycosis. its absence in peripheral blood neutrophils of members of the nuclear family of patients. an initial report.paracoccidioidomycosis (para) affects only a minority of individuals, who have presumably been exposed to the causative fungus (paracoccidioides brasiliensis). neutrophils (pmns) from patients with para show a significant and specific digestive deficiency phagocytosed p. brasiliensis in vitro. it is not known whether the defect is acquired after contact with the fungus, or precedes it. we studied the spouses and offspring of three patients with para. individuals studied stayed in the same house ...19938015557
cell wall fractions from paracoccidioides brasiliensis induce hypergammaglobulinemia.the antibody response against the antigen sheep red blood cells (srbc) was investigated in mice pre-treated with formalin-killed paracoccidioides brasiliensis or with cell wall fractions of the fungus. pre-treatment with p. brasiliensis, as well as with the fl fraction and beta-glucan significantly increased the anti-srbc antibody response in the experimental groups as compared to the control group that received only srbc. this immunomodulatory effect varied with the different doses employed and ...19938437613
immunological response to cell-free antigens of paracoccidioides brasiliensis: relationship with clinical forms of paracoccidioidomycosis.sera from patients with the acute (af) and chronic (cf) forms of paracoccidioidomycosis (pcm) were tested against paracoccidioides brasiliensis cell-free antigens by western blot (immunoblot). the cfa preparation contained components ranging in molecular mass from 18 to 102 kda. the immunoglobulin g (igg) reactivity profiles were similar for patients with both forms of the disease, and the 43-kda component was recognized by 100% of the sera. igm antibodies from the af- and the cf-pcm sera recogn ...19938458961
paracoccidioidomycosis: an update.this review summarizes knowledge on various aspects of paracoccidioidomycosis. mycelial propagules, chlamydospores, and arthroconidia exhibit thermal dimorphism; arthroconidia are infectious in animals and, by electron microscopy, appear well provided for survival. the mycelial-to-yeast-phase transformation requires a strict control of glucan synthesis probably mediated by membrane enzymes. hormonal influences on the transformation of the fungus (mycelium or conidium to yeast phase) have been de ...19938472249
identification of sialic acids on the cell surface of hyphae and yeast forms of the human pathogen paracoccidioides brasiliensis.paracoccidioides brasiliensis, the agent of paracoccidioidomycosis, when grown in a synthetic medium, expresses at the cell surface of both yeast and mycelial forms acidic glycoconjugates containing n-acetylneuraminic acid units. sialic acids were extracted using mild hydrolytic conditions, and were identified by thin-layer and gas chromatography, standard colorimetry, reaction with periodate-resorcinol and mass spectrometry. their surface location was inferred from fluorescent-lectin (limulus p ...19938472922
immunohistochemical characterization of mononuclear cells in delayed hypersensitivity reactions to paracoccidiodes brasiliensis (paracoccidioidin test).the density and distribution of t cells, t helper cells, macrophages and b cells at the site of skin tests with a cytoplasmic paracoccidioides brasiliensis antigen (paracoccidioidin) was studied at 24 and 48 h post-challenge in 10 patients with the chronic form of paracoccidioidomycosis and in 5 non-infected individuals. the in situ study was carried out using immunoperoxidase techniques and monoclonal antibodies. the controls showed negative skin test. in the patients, the great majority of the ...19938159219
histopathological alterations induced by non-viable cells and biochemical fractions from paracoccidioides brasiliensis in mice.non-viable cells and biochemical fractions from paracoccidioides brasiliensis were obtained for experimental inoculation in mice and posterior histopathological analysis. dead total fungus, total fungus disrupted by sonorous waves, lipids of the fungus, supernatant of the lipid purification, integral and disrupted fungus free of lipids were obtained. the six preparations arose from masses of lyophilized yeasts of a recent isolate of p. brasiliensis (strain jt-1) and from a "pool" equitably const ...19938246745
[paracoccidioides brasiliensis, a new sample isolated from feces of a penguin (pygoscelis adeliae)].the authors show the results obtained through the study of a paracoccidioides strain isolated from a penguin in the uruguaian antartide by gezuele et al. (1989). from the fecal mater it was isolated a fungus which was recently considered as a new species of the genus paracoccidioides--p. antarcticus. however, the mycological and immunochemical studies including the demonstration of the 43 kda glycoprotein by immunodiffusion test, sds-page and immunoelectrophoresis disclosed that such strain is s ...19938278752
dialysable leukocyte extracts modify the course of experimental paracoccidioidomycosis in the syrian hamster.the effect of dialysable leukocyte extracts (dle) obtained from hamsters immunized with paracoccidioides brasiliensis (immune dle) and from non-immunized hamsters (non-immune dle) was studied in hamsters inoculated with p. brasiliensis by the intratesticular route. treatment with immune or non-immune dle was started during the third week of infection and was repeated at 7, 11, 15 and 19 weeks. a group of untreated infected animals was used as control. animals were submitted to the delayed hypers ...19938474531
the role of the complement system in the neutrophil functions stimulated in vitro by an alkali-insoluble cell wall fraction of paracoccidioides brasiliensis.we investigated the capacity of an alkali-insoluble cell wall polysaccharide fraction (f1) of paracoccidioides brasiliensis to induce rat polymorphonuclear neutrophil (pmn) migratory and chemiluminescence (cl) responses. normal rat serum pre-incubated with f1 induced a chemotactic neutrophil response which was fully abolished by heat-inactivation. the participation of the alternative complement pathway was more effective than that of the classical pathway since depletion of factor b by heating a ...19938483056
diagnosis of paracoccidioidomycosis by passive haemagglutination assay of antibody using a purified and specific antigen-gp43.sheep red blood cells, treated with glutaraldehyde and sensitized with a purified paracoccidioides brasiliensis antigen of molecular mass 43 kda (gp43), were used to detect antibodies to p. brasiliensis by passive haemagglutination (pha). sera from 50 patients with paracoccidioidomycosis had pha titres of > 1/800, and had antibodies detectable by immunodiffusion while antibodies to gp43 were detectable by pha in sera from patients with histoplasmosis, aspergillosis, candidiasis, jorge lobo's dis ...19938509952
paracoccidioidomycosis and its etiologic agent paracoccidioides brasiliensis.paracoccidioides brasiliensis is the causative agent of paracoccidioidomycosis, a systemic mycosis endemic to latin america. in this paper we review clinical, therapeutic and immunological aspects of the disease, as well as the biology and ecology of the fungus, restricting the review to the period 1989-1992.19938509955
a preliminary study of in vitro antibiotic activity of saperconazole and other azoles on paracoccidioides brasiliensis.saperconazole, a new triazole related to itraconazole, was tested against paracoccidioides brasiliensis and results compared with ketoconazole and itraconazole. the fungus was highly sensitive to the action of these compounds, particularly saperconazole, with minimum inhibitory concentrations and minimum fungicidal concentrations ranging from 10(-7) to 10(-10) m (equivalent to 6.7 x 10(-2)-6.7 x 10(-5) micrograms ml-1 for saperconazole), according to the morphological phase and the antifungal te ...19938389848
inhibitory effect of deferoxamine or macrophage activation on transformation of paracoccidioides brasiliensis conidia ingested by macrophages: reversal by holotransferrin.conidia of p. brasiliensis ingested by murine macrophages at 37 degrees c showed enhanced transformation to yeast cells and further intracellular growth compared with conidia in culture medium alone. treatment of macrophages with the iron chelator deferoxamine inhibited the intracellular conidium-to-yeast transformation. cytokine-activated macrophages could also exert this inhibitory effect. holotransferrin reversed the inhibitory effect of either deferoxamine or activated macrophages on intrace ...19948132359
gelatinase activity of exoantigens from virulent and non-virulent isolates of paracoccidioides brasiliensis.differences in the occurrence of components with gelatinase activity were detected among four isolates of paracoccidioides brasiliensis: pb339 and pb18 (highly virulent), and pb265 and pb18av (very low virulence). culture filtrates from these isolates were electrophoresed in substrate gels and tested for gelatinase activity. pb339 showed three enzyme bands of apparent molecular masses: 43, 53 and 78 kda; pb18 had two bands, one at 59 kda and another with molecular mass higher than 78 kda. isolat ...19948207624
support of paracoccidioides brasiliensis multiplication by human monocytes or macrophages: inhibition by activated phagocytes.the interaction of human monocytes or monocyte-derived macrophages and yeast-form paracoccidioides brasiliensis was studied in vitro. yeast cells were readily ingested by adherent monocytes or macrophages. multiplication of p. brasiliensis, measured by growth as colony forming units (cfu) on a supplemented medium with good plating efficiency, was greater in monocyte co-cultures compared to the number of cfu obtained from complete tissue-culture medium (ctcm). multiplication increased with time i ...19948114064
binding of paracoccidioides brasiliensis to laminin through surface glycoprotein gp43 leads to enhancement of fungal pathogenesis.extracellular matrix protein laminin binds specifically to yeast forms of paracoccidioides brasiliensis and enhances adhesion of the fungus to the surface of epithelial madin-darby canine kidney cells in vitro. immunoblotting of fungal extracts showed that the gp43 glycoprotein is responsible for adhesion. this was confirmed by binding assays using purified gp43, with a kd of 3.7 nm. the coating of p. brasiliensis yeast forms with laminin before injection into hamster testicles enhanced the fung ...19948132354
severe acute paracoccidioidomycosis in children.this report describes clinical and immunologic features of five illustrative cases of paracoccidioidomycosis in previously healthy children. all had disseminated disease and two of them died despite treatment. the major clinical presentation in four patients was fever and diffuse superficial and intraabdominal adenopathy, with or without hepatosplenomegaly. other sites were also affected: three patients had multiple osteoarticular lesions, occasionally with intense tissue destruction; two had cu ...19948078739
comparative evaluation of chemiluminescent dna probe assays and exoantigen tests for rapid identification of blastomyces dermatitidis and coccidioides immitis.chemiluminescent dna probe (accuprobe) assays developed by gen-probe, inc. (san diego, calif.), for the rapid identification of blastomyces dermatitidis and coccidioides immitis were evaluated and compared with the exoantigen test by using 74 mycelial cultures of b. dermatitidis and 72 mycelial cultures of c. immitis. seventeen isolates of the dimorphic pathogen paracoccidioides brasiliensis were included because of their gross morphologic and antigenic relatedness to b. dermatitidis. the hetero ...19948027336
pathogenicity and immunogenicity of paracoccidioides brasiliensis isolates in the human disease and in an experimental murine model.the pathogenicity and immunogenicity of six recently isolated paracoccidioides brasiliensis samples derived from patients presenting distinct and well defined clinical forms of paracoccidioidomycosis (pcm) were compared as to their virulence, tropism to different organs and ability to induce specific cellular and humoral immune response in susceptible (b10.a) inbred mice. isolates pb44 and pb47 were obtained from acute cases, pb50 from a chronic severe form, pb45 from a chronic moderate case and ...19948033408
altered expression of surface alpha-1,3-glucan in genetically related strains of blastomyces dermatitidis that differ in virulence.recent studies of the dimorphic fungal pathogens histoplasma capsulatum and paracoccidioides brasiliensis have suggested a role in virulence for the cell surface carbohydrate alpha-(1,3)-glucan. to investigate a possible basis for alpha-(1,3)-glucan in the pathogenicity and virulence of the dimorphic fungus blastomyces dermatitidis, we examined three genetically related strains of b. dermatitidis that differ in their virulence for mice: wild-type virulent strain atcc 26199; mutant strain atcc 60 ...19948039925
immunohistochemical detection of a novel 22- to 25-kilodalton glycoprotein of paracoccidioides brasiliensis in biopsy material and partial characterization by using species-specific monoclonal antibodies.two murine monoclonal antibodies (mabs) specific to paracoccidioides brasiliensis (as determined by enzyme-linked immunosorbent assay [elisa] and western blot [immunoblot]) were produced by using a modification of standard hybridization protocols, with cyclophosphamide included as an immunomodulator to abolish responses to highly cross-reactive immunodominant epitopes. mabs ps14 and ps15 are two different clones which exhibit similar characteristics by elisa and western blot. they are directed a ...19948077405
synthesis of heat-shock proteins in mycelia and yeast forms of paracoccidioides brasiliensis.the induction of heat-shock proteins has been postulated to play a role not only in thermo-adaptation, but also in phase transition of the dimorphic fungi. in this study, we used yeast and mycelial forms of the thermally dimorphic fungus paracoccidioides brasiliensis to evaluate the effect of temperature on the induction of the heat-shock response. we also evaluated protein synthesis by p. brasiliensis caused by exposure to low ph and h2o2. analysis of protein synthesis by sds-page disclosed tha ...19948107061
phylogeny of dermatophytes and dimorphic fungi based on large subunit ribosomal rna sequence comparisons.the phylogeny of dermatophytes and dimorphic fungi was considered using the large-subunit of ribosomal rna (25s rrna). aligned sequences of 595 nucleotides covering the two most divergent domains d1 and d2, permitted a comparison of phylogenetic relationships at different levels. the dimorphic species (onygenaceae) were significantly separated from dermatophytes (arthrodermataceae) and from a third group including geophilic or very weakly pathogenic species (onygenaceae and gymnoascaceae). on a ...19947844699
classical and alternative complement pathway activation in paracoccidioidomycosis.the following study presents evidence of complement activation in paracoccidioidomycosis (pcm). twenty-eight untreated patients were studied from endemic areas of parana in southern brazil. the activation of the classical pathway, evaluated by the c4d/c4 ratio, was significantly elevated in the patients compared to the control population (p < 0.005). six patients were examined prospectively with the c4d/c4 assay during treatment and they showed a decrease in this ratio associated with clinical i ...19947921333
characterization of glycoprotein gp43, the major laminin-binding protein of paracoccidioides brasiliensis.we have demonstrated that laminin mediates the adhesion of p. brasiliensis to monolayers of epithelial cells through specific binding to the surface glycoprotein gp43. this binding seems to be related to the fungal pathogenesis. we now report the confirmation of these findings by scanning electron microscopy and show that some isolates that do not secrete gp43 do express the protein as seen by studying whole cell extracts. these results confirm the ability of these strains to produce paracoccidi ...19947787814
monoclonal antibody capture enzyme immunoassay for detection of paracoccidioides brasiliensis antibodies in paracoccidioidomycosis.four murine monoclonal antibodies (mabs 17c, 21a, 21f, and 32b) raised against the 43-kda glycoprotein of paracoccidioides brasiliensis were tested in a capture enzyme immunoassay (eia) for the detection of specific human anti-gp43 immunoglobulin g in patients with paracoccidioidomycosis (pcm). all mabs reacted similarly in the assay. these mabs, which detected anti-gp43 at levels of as low as 500 pg/ml, were demonstrated to specifically recognize at least two different epitopes in gp43 binding ...19947814469
infection and apparent invasion of vero cells by paracoccidioides brasiliensis.paracoccidioides brasiliensis probably uses many different mechanisms to establish itself in the host and cause disease. in this work, we assess an in vitro model system which uses cultured mammalian cells to investigate the virulence factors of p. brasiliensis. we were able to demonstrate an invasion process of the yeast form of this fungus in vero cell cultures. we deduced that the overall invasive process involved three steps: adhesion, followed by invasion of individual epithelial cells and ...19947965489
production and regeneration of protoplasts from the y-phase of the human pathogenic fungus paracoccidioides brasiliensis.protoplasts of y-cells and partially converted m-cells from several human isolates of paracoccidioides brasiliensis were obtained with a combined enzyme system containing novozym 234 and a chitinase. a laboratory made extract from trichoderma harzianum cbs-345-33 supplemented with chitinase induced the release of protoplasts from partially converted m-cells but not from established y-cells. a similar yield of protoplasts (1-2 x 10(5) ml-1 after 16 h) was produced by using either enzymatic system ...19947844703
experimental paracoccidioidomycosis in hamster: transmission electron microscopy of inoculation site lesion.interaction between paracoccidioides brasiliensis (pb) and inflammatory cells in hamster testis was studied sequentially by transmission electron microscopy. in early lesions (six hours after inoculation), polymorphonuclear neutrophils (pmns) were the major and mononuclear cells and eosinophils were the minor constituents of the inflammatory cells. pmns were later replaced by mononuclear cells. viable pb cells were phagocytosed or surrounded by inflammatory cells. preserved pb cells usually had ...19947855485
delayed-type hypersensitivity response in an isogenic murine model of paracoccidioidomycosis.the specific delayed-type hypersensitivity (dth) response was evaluated in resistant (a/sn) and susceptible (b10.a) mice intraperitoneally infected with yeasts from a virulent (pb18) or from a non-virulent (pb265) paracoccidioides brasiliensis isolates. both strains of mice were footpad challenged with homologous antigens. pb18 infected a/sn mice developed an evident and persistent dth response late in the course of the disease (90th day on) whereas b10.a animals mounted a discrete and ephemeral ...19947935728
[paracoccidioidomycosis evidencing spinal cord involvement treated with success by fluconazole].the involvement of central nervous system in paracoccidiodomycosis has rarely been described, with an incidence rate varying from 9.99% to 27.27%. there are two basic forms of clinical presentation: meningeal and tumor-like (abscesses, granulomas, nodules, and cysts). the paracoccidioides brasiliensis is preferentially described in cerebral hemispheres, cerebellum, medulla oblonga and meninges, and exceptionally in the spinal cord. the authors present a case of paracoccidioidomycosis which diagn ...19948002815
chromosome aberrations in lymphocyte cultures from paracoccidioidomycosis patients.blood cell lymphocyte chromosomes from untreated (ut) and clinically-cured (cc) patients with paracoccidioidomycosis and from healthy (control) people (co) were studied. the frequency of aneuploid cells in the ut patients was higher than in the cc and co individuals. the frequency of metaphase cells with premature centromere division was significantly higher in the ut than in the cc and co group. no structural aberration and no statistically significant difference in the frequency of polyploidy ...19947965490
alkaline phosphatase at the cell wall of the yeast phase of paracoccidioides brasiliensis.the activity of alkaline phosphatase demonstrated by histochemical techniques was shown at the cell wall of the yeast form of paracoccidioides brasiliensis at 3, 6, and 9 days of culture. the results showed a very active deposition at the cell wall as early as 9 days of culture of the fungus which made us think an inactive salt precipitate was also present.19947984214
[the evaluation of ketoconazole in mice inoculated with paracoccidioides brasiliensis by liver and spleen histopathology and by the intradermal paracoccidioidin reaction].male albino mice were inoculated intravenously with 0.5 x 10(7) viable yeast forms of p. brasiliensis (strain 2052). these animals were treated with two doses of ketoconazole (50 and 100 mg/kg) during fifty days and the sacrificed. we studied the presence of p. brasiliensis, the inflammatory granulomatous response of liver and spleen and the anti p. brasiliensis delayed hypersensitivity response measured by the footpad test after 48 hours. it was observed that: 1. animals infected and treated wi ...19948008914
paracoccidioidin and histoplasmin sensitivity in tupí-mondé amerindian populations from brazilian amazonia.a cross-sectional epidemiological survey for paracoccidioidomycosis and histoplasmosis, including skin tests with paracoccidioidin and histoplasmin, physical examinations and x-rays, was conducted among three tupí-mondé amerindian populations from brazilian amazonia. the study followed the diagnosis of an increasing number of cases of paracoccidioidomycosis among the suruí in recent years. positivity rates to paracoccidioidin and histoplasmin (> or = 5 mm of intradermal induration 24-48 h post-i ...19948067815
viability and morphological alterations of paracoccidioides brasiliensis strains preserved under mineral oil for long periods of time.we evaluated the survival and the morphological alteration of 70 strains of paracoccidioides brasiliensis maintained in the fungal culture collection of institute oswaldo cruz and initially preserved by successive subculturing and later under mineral oil at room temperature from 1923 to 1992. of the 70 strains preserved under mineral oil, 18 (26%) continued to be viable. the mycelia of the 18 viable strains and the mycelia of four representatives of the non-viable strains presented transitional ...19947898512
experimental paracoccidioidomycosis of hamster inoculated in the cheek pouch.we compared the granuloma morphology and immune response of hamsters inoculated with paracoccidioides brasiliensis (pb) into the cheek pouch, which lacks lymphatic drainage, and into the footpad, which is rich in lymphatics. our objective was to better understand the modulation of pb granuloma in an immunocompetent animal inoculated in an immunologically privileged site. the humoral immune response (elisa) and cell mediated immunity (footpad test) became positive on days 7 and 14, respectively i ...19947777036
fibrosis patterns of lesions developed by athymic and euthymic mice infected with paracoccidioides brasiliensis.athymic and euthymic mice with balb/c background were used to study the patterns of fibrosis during ip infection with a virulent isolate of paracoccidioides brasiliensis. specimens from various organs were collected from the animals at 1, 4 and 7 weeks after infection and observed under light microscopy using various histologic staining methods. lesions from the first week of infection, in both animal groups, presented a predominance of collagen iii over i, carboxylated proteoglycans, and a tend ...19947787813
involvement of cell wall glucans in the genesis and persistence of the inflammatory reaction caused by the fungus paracoccidioides brasiliensis.the role of cell wall polysaccharides in leucocyte recruitment and granuloma formation in paracoccidioidomycosis was investigated. the inflammatory cells recruitment to the peritoneal cavity in rats inoculated with cell wall fraction (cw-265 or f1-265) from an avirulent strain of paracoccidioides brasiliensis (pb265), was greater than that observed for the cell wall fraction (cw-hc or f1-hc) recovered from the virulent strain (pbhc). moreover, the inoculation of f1-hc and f1-265 into the subcuta ...19948025684
phylogenetic spectrum of fungi that are pathogenic to humans.recent phylogenetic studies based on ribosomal rna sequences have confirmed that the organisms traditionally treated as fungi include those that have evolved from several different lines (multiphyletic organisms), as has been suspected. even organisms causing disease in humans represent at least two evolutional lines. pythium insidiosum and prototheca species are both believed to have evolved from one line, while the rest of the pathogens have evolved from another line. p. insidiosum is more clo ...19947948565
human alpha beta and gamma delta t cells from unexposed individuals respond to protein antigens of the yeast form of paracoccidioides brasiliensis.paracoccidioides brasiliensis, a dimorphic fungus, causes chronic granulomatous mycosis in susceptible individuals. different reports have shown that cell-mediated immunity is essential for protection against systemic mycosis, including paracoccidioidomycosis. we analyzed the reactivity of alpha beta and gamma delta t cells from unexposed caucasian donors to p. brasiliensis yeast form components. our results indicate: (i) alpha beta and gamma delta t cells proliferate after in vitro stimulation ...19947865465
chemiluminescent immunoassays: discrimination between the reactivities of natural and human patient antibodies with antigens from eukaryotic pathogens, trypanosoma cruzi and paracoccidioides brasiliensis.quantitative chemiluminescent enzyme-linked immunosorbent assay (elisa) and dot-blotting procedures were developed to evaluate the reactivity of human antibodies with crude antigens and purified molecules of parasites and fungi, mainly trypanosoma cruzi and paracoccidioides brasiliensis. reproducible, highly sensitive, and strictly dose-responding results were obtained, with the specificity depending on the kind of antigen used. mixed antigens (epimastigote membrane and hiv-1 heptapeptide) appli ...19947869183
fungal polysaccharides.fungal polysaccharides are cell wall components which may act as antigens or as structural substrates. as antigens, the role of mannans in saccharomyces cerevisiae and candida albicans, and of glycoproteins in aspergillus fumigatus are discussed. analyses on beta-glucan synthetase in paracoccidioides brasiliensis and the inhibitory effect of hansenula mrakii killer toxin on beta-glucan biosynthesis are also considered.19947536840
nature of the reactive epitopes in paracoccidioides brasiliensis polysaccharide antigen.fava nettos' polysaccharide antigen (fnpa), shown to detect humoral and cellular responses in paracoccidioidomycosis, was investigated. skin tests with fnpa were negative after alkaline hydrolysis or depletion of gp43 peptide epitopes. purified antibodies to fnpa or gp43 from paracoccidioidomycosis patients cross-reacted, showing common epitopes and fnpa-specific ones. normal human sera, in contrast to paracoccidioidomycosis sera, were unreactive with gp43 but recognized epitopes of fnpa suscept ...19947515959
plasma amylase levels as a marker of disease severity in an isogenic murine model of paracoccidioidomycosis.survival patterns after peritoneal infection with paracoccidioides brasiliensis vary according to the mouse strain and to the virulence of the fungal isolate. it has previously been observed that a significant increase in plasma amylase levels occurs only when susceptible mice (b10.a) were infected with a virulent isolate (pb18). in order to verify if increased amylase levels correlate with susceptibility to p. brasiliensis infection, 12 mouse strains with different susceptibility patterns to th ...19947515958
paracoccidioides brasiliensis protoplast production by enzymatic treatment.the action of the enzymes novozym 234, chitinase and zymolyase 20t on the yeast-like cells of paracoccidioides brasiliensis was studied in an attempt to obtain protoplast release. three enzyme systems were used: the first consisted of novozym 234 and chitinase plus 0.2 m phosphate buffer, 0.9 m sorbitol and 0.5 m sodium thioglycolate; the second consisted of novozym 234, chitinase, zymolyase 20t, buffer and osmotic stabilizer, with no sodium thioglycolate; the third consisted of the same enzymes ...19947746289
structural alterations in candida albicans by caffeine and caffeine salts.cytological alterations of candida albicans following exposure to subinhibitory concentrations of caffeine and caffeine salts were examined by light and transmission electron microscopy (tem). the effect was different from that induced by ketoconazole. caffeine and especially caffeine salts caused an increase in unusual modes of proliferation with signs of multiple budding in candida albicans. structurally, such yeast cells present some resemblance to paracoccidioides brasiliensis.19947746292
characterization of paracoccidioides brasiliensis isolates by random amplified polymorphic dna analysis.we initially used 25 different random primers in order to test their ability to generate random amplified polymorphic dna fragments from the dimorphic human pathogenic fungus paracoccidioides brasiliensis. from the tested primers we chose five to distinguish between seven isolates of this microorganism. the dna amplification patterns allowed clear differentiation of the seven isolates into two distinct groups with only 35% genomic identity. one of these groups contained two subgroups with 81% ge ...19957714219
effect of macrophage blockade on the resistance of inbred mice to paracoccidioides brasiliensis infection.the effect of macrophage blockade on the natural resistance and on the adaptative immune response of susceptible (b10.d2/osn) and resistant (a/sn) mice to paracoccidioides brasiliensis infection was investigated. b10.d2/osn and a/sn mice previously injected with colloidal carbon were infected ip with yeast cells to determine the 50% lethal dose, and to evaluate the anatomy and histopathology, macrophage activation, antibody production and dth reactions. macrophage blockade rendered both resistan ...19957566066
unraveling the secrets of histoplasma capsulatum. a model to study morphogenic adaptation during parasite host/host interaction.early in the developmental period of microbiology, pasteur first observed the phenomenon of dimorphism in fungi when he noticed that the bread mold mucor grew as a filamentous mold aerobically on the surface of broth cultures but at the bottom of the flask where the environment was anaerobic it reproduced as budding yeast cells. several infectious fungal pathogens of humans, namely histoplasma capsulatum, blastomyces dermatitidis, paracoccidioides brasiliensis, sporothrix schenkii, and coccidioi ...19957571855
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