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natural cell-mediated resistance against cryptococcus neoformans: a possible role for natural killer (nk) cells. 19853916764
pleural effusions due to cryptococcus neoformans: a review of the literature and report of two cases with cryptococcal antigen determinations.pleural effusions due to cryptococcus neoformans occurred in 2 patients, 1 with localized pulmonary infection and 1 with disseminated cryptococcosis. cryptococcal antigen was present in the pleural fluid from both patients and it was present also in the serum and cerebrospinal fluid of the patient with disseminated infection. the cryptococcal antigen test is a sensitive and specific indicator of cryptococcoal infection, and it was not positive in pleural fluid samples from a variety of other con ...19806992663
t-cell-dependent and t-cell-independent mechanisms of tolerance to glucuronoxylomannan of cryptococcus neoformans serotype a.glucuronoxylomannan (gxm), a type 2 t-independent antigen, is the major component of the capsular polysaccharide (cncap) of cryptococcus neoformans. previous studies have described the tolerogenic effects of high doses of cncap on the specific humoral response. in this investigation, evidence for both high-dose and low-dose tolerance to gxm is presented. balb/cby female mice, primed with either 5 ng or 50 micrograms of gxm, then coimmunized 3 days later with immunogenic doses of both gxm and typ ...19938095924
cryptococcal meningitis and confusional psychosis. a case report and literature review.a previously healthy and immuno-competent 22-year-old man presented in confusional psychosis. cryptococcal meningitis was later found to be the underlying cause as proven by culturing cryptococcus neoformans serotype a from the cerebrospinal fluid. combined antifungal therapy with amphotericin b and 5-fluorocytosine resulted in sustained improvement of all mental and physical functions. cryptococcosis has rarely been reported from the middle east. this represents the second case from kuwait.19958553450
pathogenic yeast-like fungi in meat products.100 samples of sausage and ham (cut in fine slices) were examined to find out whether meat products can harbour yeast-like fungi pathogenic for man. pieces of the test material were placed in a sterile petri dish containing 1 ml distilled water and incubated at 26 degrees c for 2 days. the colonies grown on the material were identified by international standard methods, tested for extracellular proteolytic activity and serotypes. experimentally infected meat products were studied culturally and ...19807013360
chemical characterization of capsular polysaccharide from cryptococcus neoformans serotype a-d.during a study of serotyping of cryptococcus neoformans, we found that the type strain of c. neoformans (cbs 132) was serotype a-d. this strain agglutinated with both factor 7 serum (specific for serotype a) and factor 8 serum (specific for serotype d) in our serotyping system. therefore, we investigated the chemical structure of the antigenic capsular polysaccharide of this strain. the soluble capsular polysaccharide was obtained from the culture supernatant fluid by precipitation with ethanol. ...19853908888
isolates of cryptococcus neoformans serotype a or d from cerebrospinal fluid resistant to 5-fluorocytosine. 19958904119
binding of purified and radioiodinated capsular polysaccharides from cryptococcus neoformans serotype a strains to capsule-free mutants.strains 6, 15, 98, 110, and 145 of cryptococcus neoformans serotype a vary in capsule size, animal virulence, and susceptibility to in vitro phagocytosis. the isolated capsular polysaccharides (cpss) differ in monosaccharide composition ratios and molecular size, as determined by gel filtration. the purpose of this investigation was to characterize the binding of cpss to capsule-free mutants of c. neoformans and to examine cpss from these strains for differences in their ability to bind, to dete ...19863536747
strain variation in composition and molecular size of the capsular polysaccharide of cryptococcus neoformans serotype a.the capsule of cryptococcus neoformans is an important virulence factor. in this investigation capsular polysaccharides (cpss) were isolated by ethanol precipitation from culture filtrates of c. neoformans serotype a strains 6, 15, 98, 110, and 145. capsule sizes on india ink examination ranged from barely perceptible (strain 15) to greater than the diameter of the yeast cell (strain 6); the others were intermediate in size. on ion-exchange chromatography on deae-cellulose each cps eluted at 0.2 ...19863536746
structure determination of cryptococcus neoformans serotype a-variant glucuronoxylomannan by 13c-n.m.r. spectroscopy.a series of polysaccharides was derived by physical and chemical methods from an antigenic, o-acetyl-containing, glucuronoxylomannan (gxm), isolated from the growth medium of cryptococcus neoformans (cdc b2550) serotype a-variant having composition ratios of man:xyl:glca:oac = 10:4:3:6. 13c-n.m.r. spectra of derivatives provided new structural evidence for gxm. treatment of gxm with li in ethylenediamine gave a xylomannan (xm, with man:xyl = 5:2). smith degradation of xm gave a mannan (m). ultra ...19883280130
cryptococcus neoformans: a central nervous system isolate from an aids patient that is rhinotropic in a normal mouse model.a strain of cryptococcus neoformans that was isolated from the cerebrospinal fluid of a human diagnosed as having acquired immunodeficiency syndrome (aids), and that produced cutaneous lesions in experimentally infected, normal mice is described. although no unusual cutaneous manifestations were noted in the patient's records, this isolate of c. neoformans proved to be dermotropic when injected intravenously into cd-1 mice. the ld50 at 28 days post infection ranged from 3.6-7.5 x 10(5) cells per ...19883043225
characterization of cryptococcus neoformans capsular glucuronoxylomannan polysaccharide with monoclonal antibodies.mice were immunized with cryptococcus neoformans serotype a capsular glucuronoxylomannan (gxm) conjugated to bovine serum albumin-adipic dihydrazide. two splenocyte fusions yielded two monoclonal antibodies (mabs) that were highly reactive in dot enzyme immunoassay, immunofluorescence, and sandwich enzyme immunoassay. the first mab, bd-1 [immunoglobulin g1 (kappa) [igg1(kappa)]], was gxm-a and gxm-d specific, whereas the second mab, ba-4 (igm), reacted with gxm-a and gxm-b. a third mab, cd-6 [ig ...19892680986
strain variation in antiphagocytic activity of capsular polysaccharides from cryptococcus neoformans serotype a.strains of cryptococcus neoformans vary in resistance to phagocytosis in vitro. the binding of isolated capsular polysaccharide (cps) to a capsule-free mutant of c. neoformans confers resistance to phagocytosis. the importance of capsule composition to differences among strains in susceptibility to phagocytosis was evaluated. cpss from five strains of c. neoformans serotype a, designated 6, 15, 98, 110, and 145, which had previously been isolated and characterized as to molecular size, compositi ...19892680980
cryptococcus neoformans serotype a glucuronoxylomannan-protein conjugate vaccines: synthesis, characterization, and immunogenicity.we synthesized cryptococcus neoformans serotype a glucuronoxylomannan (gxm) conjugate vaccines under conditions suitable for human use to prevent disseminated cryptococcosis. the purified, sonicated gxm was derivatized with adipic acid dihydrazide through either hydroxyl or carboxyl groups and then covalently bound to tetanus toxoid (tt) or pseudomonas aeruginosa exoprotein a (repa). the immunogenicity of these conjugates was evaluated in balb/c and general purpose mice by subcutaneous injection ...19911716613
reassessment of antigenic determinant of saccharomyces cerevisiae serotype ia.we examined the immunochemical structure of the antigenic determinant of s. cerevisiae serotype ia. the specific factor serum for s. cerevisiae serotype ia was obtained either from factor 18 serum by adsorption with heat-killed cells of candida glabrata, or from anti-s. cerevisiae ia (m 6001) serum by adsorption with heat-killed cells of s. cerevisiae ib (ifo 0751). we designated this adsorbed serum as factor 18a. acetolysis of s. cerevisiae cell wall d-mannan gave five oligosaccharides. signals ...19901706464
susceptibility testing of cryptococcus neoformans: a microdilution technique.we studied a series of test conditions in a microtiter system to define the optimal method for determining the susceptibility of cryptococcus neoformans to antifungal agents. twenty-one isolates of c. neoformans were grown for 24 or 48 h in four chemically defined media: yeast nitrogen base (bynb 7); rpmi 1640; synthetic amino acid medium--fungal (saamf), buffered at ph 7.0 to select the medium that best supported growth of this fastidious yeast; and yeast nitrogen base, ph 5.4 (ynb 5.4). maximu ...19921452658
[cryptococcus neoformans: a rare cause of basal meningitis]. 19807428618
molecular typing of cryptococcus neoformans serotype d clinical isolates.cryptococcus neoformans serotype a is responsible for the majority of cryptococcal infections in aids patients. in france, approximately 17% of the patients are infected with serotype d, regardless of their human immunodeficiency virus status. in a retrospective study of 273 patients, we found that serotype d was unevenly distributed in france. we wondered if this was related to the yeast's genetic background. we used karyotyping and dna fingerprints generated by ut-4p to analyze 40 serotype d c ...19947814467
capsular polysaccharides from a parent strain and from a possible, mutant strain of cryptococcus neoformans serotype a. 19817028261
olfactory mucosa response in guinea pigs following intranasal instillation with cryptococcus neoformans. a histological and immunocytochemical study.a central nervous system isolate from an acquired immunodeficiency syndrome (aids) patient of 10(3) cryptococcus neoformans cells was instilled intranasally into guinea pigs. these were killed to evaluate the fate of the organisms and the response of the olfactory mucosa. olfactory epithelium prevented the penetration of cryptococcus neoformans and showed focal hyperplastic responses. the organisms, which manifested an affinity for the olfactory portion of the nasal cavities, were cleared from t ...19948065433
improvement of amphotericin b activity during experimental cryptococcosis by incorporation into specific immunoliposomes.cryptococcosis is an opportunistic infection that is responsible for increased morbidity and mortality in patients with the acquired immunodeficiency syndrome. the high toxicity of the antifungal agent that is mainly used against cryptococcosis, amphotericin b (amb), accounts for the need for new treatments, especially in patients with the acquired immunodeficiency syndrome because of the high relapse rate of cryptococcosis. drug targeting may be one of these alternate treatments. since we have ...19902073097
urokinase is required for the pulmonary inflammatory response to cryptococcus neoformans. a murine transgenic model.urokinase (upa) is hypothesized to provide proteolytic activity enabling inflammatory cells to traverse tissues during recruitment, and it is implicated as a cytokine modulator. definitive evaluation of these hypotheses in vivo has previously been impossible because upa could not completely and irreversibly be eliminated. this limitation has been overcome through the development of upa-deficient transgenic mice (upa-/-). using these mice, we evaluated the importance of upa in the pulmonary infla ...19968621764
charcoal particle agglutination test for detection of antibody to cryptococcus neoformans: a preliminary report. 19715094496
structural variability in the glucuronoxylomannan of cryptococcus neoformans serotype a isolates determined by 13c nmr spectroscopy.cryptococcus neoformans, the etiologic agent of cryptococcal meningoencephalitis, produces glucuronoxylomannan (gxm) as the major capsule component. purified gxms obtained from eight serotype a isolates of c. neoformans were treated by ultrasonic irradiation and then o-deacetylated prior to their comprehensive chemical analysis by glc, glc-ms, and 13c nmr spectroscopy. the average xylose: mannose: glucuronic acid molar ratio of the eight isolates is 1.96 +/- 0.25: 3.00: 0.58 +/- 0.10. methylatio ...19921446309
[temperature resistance of cryptococcus neoformans--a contribution to epidemiology]. 19807008774
a 77-kilodalton protein of cryptococcus neoformans, a member of the heat shock protein 70 family, is a major antigen detected in the sera of mice with pulmonary cryptococcosis.heat shock proteins (hsps) from several pathogenic microbes have been shown to be target molecules of humoral responses as well as cellular immune responses. however, little is known about target molecules in pulmonary cryptococcosis. western blotting analysis revealed that experimentally induced pulmonary cryptococcosis in (balb/c x dba/2)f1 mice was associated with the appearance of serum antibodies to a 77-kda protein derived from cryptococcus neoformans as well as to 18-, 22-, 25-, 36-, and ...19979125543
phospholipase activity in cryptococcus neoformans: a new virulence factor?fifty isolates of cryptococcus neoformans were examined for extracellular phospholipase production after inoculation onto egg yolk agar; 49 produced a pericolonial precipitate indicative of phospholipase activity. phospholipase b (plb), lysophospholipase, and lysophospholipase-transacylase activities were identified by radiometric analysis in supernatants from 4 clinical isolates. the ratio of colony diameter to colony plus precipitate on agar (pz) correlated with plb activity. phospholipase pro ...19979203663
influence of different conditions on kinetics of tumor necrosis factor alpha release by peripheral blood mononuclear cells after stimulation with cryptococcus neoformans: a possible explanation for different results.in available literature, different kinetics for tumor necrosis factor alpha (tnf-alpha) release by peripheral blood mononuclear cells are reported upon stimulation with cryptococcus neoformans. results in this study showed that shaking cells gives faster kinetics of tnf-alpha release while large working volumes give lower tnf-alpha concentrations. different experimental conditions thus influence kinetics of tnf-alpha release by phagocytes.19979384311
in vitro and in vivo antifungal activity of the combination methylpartricin-5-fluorocytosine.in vitro studies on the antifungal activity exerted by the combinations spa-s-222 (a hydrosoluble derivative of the polyene antibiotic methylpartricin) and 5-fluorocytosine evidence a favourable interaction against the formation of germ-tube in candida albicans; against cryptococcus neoformans and 5fc induced-resistant strains of candida albicans. in the experimental infections with candida albicans and cryptococcus neoformans a significantly favourable interaction was exerted by polyene-5fc com ...19846398120
type-specific polysaccharides of cryptococcus neoformans. n.m.r.-spectral study of a glucuronomannan chemically derived from a tremella mesenterica exopolysaccharide.a glucuronomannan (gm) was derived by removal, through smith degradation, of xylose from the native (3-o-acetylglucurono)xylomannan exopolysaccharide isolated from tremella mesenterica. 13c-n.m.r. chemical shifts measured at various pd values were compared for p-nitrophenyl beta-d-glucopyranosiduronic acid (1) and two gms (2 and 3) differing in glca content (man:glca; 2, 10:1; and 3, 5:1). also measured and compared were pka values for 1 and 2. one-dimensional and two-dimensional (cosy and hetco ...19883072079
atypical cytomorphologic appearance of cryptococcus neoformans: a report of five cases.cryptococcus neoformans is not generally recognized as producing pseudohyphae. although atypical morphologic forms have been described in the microbiology literature, we believe this is the first complete cytologic report describing this uncommon and unusual cytologic appearance of cryptococcal infection.19968629428
what makes cryptococcus neoformans a pathogen?life-threatening infections caused by the encapsulated fungal pathogen cryptococcus neoformans have been increasing steadily over the past 10 years because of the onset of aids and the expanded use of immunosuppressive drugs. intricate host-organism interactions make the full understanding of pathogenicity and virulence of c. neoformans difficult. we discuss the current knowledge of the characteristics c. neoformans must possess to enter the host and establish progressive disease: basic growth r ...19989452400
the different binding patterns of two immunoglobulin m monoclonal antibodies to cryptococcus neoformans serotype a and d strains correlate with serotype classification and differences in functional assays.cryptococcus neoformans var. neoformans strains have historically been divided into serotypes a and d on the basis of reactivity with rabbit sera. previously, we noted that two murine immunoglobulin m monoclonal antibodies (mabs) to the capsular glucuronoxylomannan produced different indirect immunofluorescence (if) patterns, described as annular and punctate, when bound to c. neoformans cells from different strains. in this study, we examined the reactivity of these two mabs, known as 12a1 and ...19989521132
immunoreactivity of cryptococcal antigen is not stable under prolonged incubations in human serum.the stability of cryptococcal antigen from cryptococcus neoformans serotype a and d strains at different temperatures in serum and other solvents was studied. samples stored at -20 or 4 degrees c had equivalent stabilities as measured by the premier cryptococcal antigen kit and the cryptococcal antigen latex agglutination system (calas) kit. however, using the premier cryptococcal antigen kit, there was a 91% loss of reactivity in samples incubated in human serum for 4 weeks at 37 degrees c. a l ...200415184471
the invasive behaviour of cryptococcus neoformans: a possibility of direct access to the central nervous system?cryptococcocal meningoencephalitis is always considered secondary to initial lung infection. because of the unquestionable evidence of haematogenious spread from the lungs, few publications have reported about other possible primary sites of infection or other routes to the central nervous system. this study was designed to investigate the infiltrative pattern of c. neoformans in immunocompromised mice by treatment with dexamethasone. the infection was performed by nasal instillation (30 mice) o ...19979608719
tissue changes in cryptococcosis: histologic alteration from gelatinous to suppurative granulomatous tissue response with asteroid body.the histologic variety and transformation in cutaneous cryptococcosis with acute lymphocytic leukemia before antifungal treatment and after the start of treatment were studied by the light and electron microscopic examinations. the initial cutaneous lesions before treatment revealed gelatinous tissue reactions, and cryptococcus neoformans (serotype a) were isolated from the skin biopsy specimen and blood. however, later recurrent cutaneous lesions receiving antifungal treatment revealed suppurat ...19892677734
an anti-cryptococcus neoformans monoclonal antibody directed against galactoxylomannan.six monoclonal antibodies (mab) were produced by immunizing mice with a cryptococcus neoformans serotype a spheroplast lysate (cnsl). two mab were of the igg1 isotype; the others were igm. the results obtained with one igm mab (cn6) are reported herein. this mab recognized the four serotypes of c. neoformans and no cross-reactions were observed with extracts from cryptococcus melibiosum, candida albicans, saccharomyces cerevisiae, torulopsis glabrata or trichosporon beigelii. fractionation of th ...19902189167
structure and antigenic activity of the capsular polysaccharide of cryptococcus neoformans serotype a. 19806777664
the glucuronoxylomannan of cryptococcus neoformans serotype a is a type 2 t-cell-independent antigen.the humoral immune response of inbred mice to immunization with the glucuronoxylomannan (gxm) of cryptococcus neoformans was investigated both serologically and in plaque-forming cells (pfcs). the t-helper-cell-independent quality of the gxm was demonstrated by using balb/c nu/nu mice. primary and secondary dose responses to three antigenic forms of gxm, (i) the native antigen, (ii) a gxm-bovine serum albumin protein conjugate, and (iii) a cryptococcal whole-cell vaccine, revealed a lack of isot ...19921398921
kinetics of lymphocyte transformation in mice immunized with viable avirulent forms of cryptococcus neoformans.a murine model was developed to study the cell-mediated immune response of mice immunized with one of two live, avirulent forms of cryptococcus neoformans: a nonencapsulated mutant and a thinly encapsulated pseudohyphal variant. a lymphocyte transformation assay was used to evaluate the cellular response of control and sensitized spleen cells after in vitro incubation with three merthiolate-killed whole-cell antigens of c. neoformans. an antigen-to-spleen cell ratio of 10:1 and 5 days of incubat ...1979378854
environmental strains of cryptococcus neoformans variety grubii in the city of santos, sp, brazil.this study involved a total of 116 samples, 79 taken from pigeon droppings and 37 of atmospheric air taken close to accumulations of excrement. cryptococcus neoformans var. grubii was isolated from 11 (13.9%) of these samples. other species of cryptococcus were also isolated from these samples, such as c. albidus (12.6%) and c. laurentii (8.9%). c. neoformans was not isolated from the air samples, though c. albidus (5.4%) was. all the strains of c. neoformans were found to belong to the a seroty ...200515729472
influence of shaking on antifungal susceptibility testing of cryptococcus neoformans: a comparison of the nccls standard m27a medium, buffered yeast nitrogen base, and rpmi-2% glucose.cryptococcus neoformans is a nonfermentative yeast that requires oxygen for growth. the shaking of culture media achieves good oxygenation, promoting the growth of cryptococci. in this study, three test media (rpmi 1640, rpmi 1640-2% glucose, and buffered yeast nitrogen base ¿bynb) recommended in the national committee for clinical laboratory standards m27a standard were examined. growth abilities and minimum inhibitory concentrations (mics) in microplates incubated at 35 degrees c for 48 h were ...200010639369
prevalence of cryptococcus neoformans var. neoformans (serotype d) and cryptococcus neoformans var. grubii (serotype a) isolates in new york city.analysis of 40 new york city cryptococcus neoformans isolates revealed that 39 were typeable, of which 85 and 12.5% were cryptococcus neoformans var. grubii (serotype a) and cryptococcus neoformans var. neoformans (serotype d), respectively. the prevalence of serotype d isolates in new york city appears to be significantly higher than indicated by previous studies of north american isolates.200010790132
in vivo clearance of glucuronoxylomannan, the major capsular polysaccharide of cryptococcus neoformans: a critical role for tissue macrophages.cryptococcus neoformans produces a life-threatening meningitis in patients who are immunocompromised by aids. a striking feature of cryptococcosis in aids is high serum levels of the major capsular polysaccharide, glucuronoxylomannan (gxm). soluble gxm has numerous biologic activities that may contribute to the pathogenesis of infection. the objective of the study was to further understand in vivo processing of gxm. mice were injected intravenously with gxm, and the tissue distribution was deter ...200111471106
isolation of a cryptococcus neoformans serotype a mata strain from the italian environment.cryptococcus neoformans is a heterothallic basidiomycete which possesses a bipolar mating system based on two mating type alleles, mata and matalpha. in the type variety, c. neoformans var. neoformans, both mating types have been found among strains of one serotype, serotype d, whereas only matalpha was identified after extensive survey of serotype a strains. serotype a ma ta appeared to be extinct or to exist only in a vestigial, non-functional form. we report the isolation of a c. n. var. neof ...200112054047
enhanced binding of capsular polysaccharides of cryptococcus neoformans to polystyrene microtitration plates for enzyme-linked immunosorbent assay.a sensitive enzyme-linked immunosorbent assay (elisa) to measure antibodies against capsular polysaccharide was developed, based on the enhanced binding of polysaccharide to polystyrene microtitration plates. the wells of the microtitration plate were primed with an adipic acid dihydrazide derivative of bovine serum albumin (ah-bsa) (100 micrograms/ml, 0.01 m napo4-0.14 m nacl, ph 7.2 (pbs]. capsular polysaccharide, the glucuronoxylomannan of cryptococcus neoformans serotype a, was oxidized with ...19883064947
a note on the isolation of cryptococcus neoformans serotype a mata strain from the italian environment.the first known mating-competent isolate of cryptococcus neoformans serotype a mata (cbs 9172/atcc mya 2742), recently reported, was found during an environmental study of a rural aviary in the italian province of apulia. data are presented to facilitate the finding of more such isolates.200212521123
sequence length required for homologous recombination in cryptococcus neoformans.cryptococcosis is a major threat to immunocompromised individuals. isolates of cryptococcus neoformans var. grubii and var. neoformans are responsible for most of the infections in the united states and europe. in depth analysis of the virulence phenotype of this organism requires the generation of specific gene disruptions. the minimum sequence requirements for efficient homologous recombination has not been determined in cryptococcus. to investigate the flanking dna length requirements for eff ...200312553931
disseminated cryptococcosis in an aids patient caused by a canavanine-resistant strain of cryptococcus neoformans var. grubii.a case of disseminated cryptococcosis caused by cryptococcus neoformans var. grubii is presented in a male diabetic who had aids. the diagnosis was based upon the isolation and identification of the aetiological agent from a lymph-node biopsy, cerebrospinal fluid and sputum. the isolate formed spherical, encapsulated yeast cells, produced cherry-brown colonies on niger-seed agar, grew on canavanine-glycine-bromothymol blue (cgb) medium, changing its colour from greenish yellow to blue, and hydro ...200312621094
sexual cycle of cryptococcus neoformans var. grubii and virulence of congenic a and alpha isolates.cryptococcus neoformans is a human-pathogenic fungus that has evolved into three distinct varieties that infect most prominently the central nervous system. a sexual cycle involving haploid cells of a and alpha mating types has been reported for two varieties (c. neoformans var. neoformans, serotype d, and c. neoformans var. gattii, serotypes b and c), yet the vast majority of infections involve a distinct variety (c. neoformans var. grubii, serotype a) that has been thought to be clonal and res ...200312933823
3-hydroxyanthranilate in cryptococcus neoformans: a secreted reductant that does not enable wood rot.cryptococcus neoformans secretes 3-hydroxyanthranilate (3haa), but the utility is unknown. exogenous 3haa promoted growth of cultures starved for iron with transferrin, presumably by releasing fe(iii) reductively. exogenous 3haa protected c. neoformans from strong oxidants, suggesting a role in resistance to killing by immune cells. 3haa represents an endogenous laccase substrate, in that crude laccase preparations convert 3haa to cinnabarinic acid, whereas 3haa concentrations are higher in lac- ...200312964724
structure of the 13c-enriched o-deacetylated glucuronoxylomannan of cryptococcus neoformans serotype a determined by nmr spectroscopy.the complete assignment of 1h and 13c chemical shifts for 99% uniformly 13c-labeled o-deacetylated glucuronoxylomannan (gxm) of cryptococcus neoformans serotype a isolate 9759-mu-1 was accomplished by the analysis of hcch-tocsy and hcch-cosy spectra. the sequence of the glycosyl residues was determined by a ghmbc experiment using 20% uniformly 13c-labeled gxm; gxm was prepared by a novel procedure that insured the virtual exclusion of adjacent 13c-labeled carbon atoms. for each residue in the gx ...19979228737
cloning of cnlyso1, a novel extracellular lysophospholipase of the pathogenic fungus cryptococcus neoformans.we cloned a novel lysophospholipase (cnlyso1) from cryptococcus neoformans var. grubii by pcr amplification and a cdna library screen. the open reading frame (orf) of 1278 nucleotides coded for a predicted 426-amino-acid protein (cnlyso1p) with two highly conserved gxsxg lipase-specific catalytic motifs and a molecular weight of 48.3 kda. cnlyso1p exhibited 14% and 21% identity to arabidopsis thaliana and human lysophospholipases, respectively. immunoprecipitation and western blot analyses indic ...200314563553
isolates of cryptococcus neoformans serotype a and d developed on canavanine-glycine-bromthymol blue medium.two isolates of cryptococcus neoformans serotype a and one isolate of serotype d from pigeon droppings were found to grow on canavanine-glycine-bromthymol blue (cgb) medium, when the japanese isolates of cr. neoformans were examined for their serotype and biochemical characteristics. the susceptibility to canavanine and the activity in assimilation of glycine were analysed on these three isolates. they were resistant to canavanine at the high concentration of 3.6 mmol l-1 and developed by assimi ...19989610131
cyclic amp-dependent protein kinase catalytic subunits have divergent roles in virulence factor production in two varieties of the fungal pathogen cryptococcus neoformans.our earlier findings established that cyclic amp-dependent protein kinase functions in a signaling cascade that regulates mating and virulence of cryptococcus neoformans var. grubii (serotype a). mutants lacking the serotype a protein kinase a (pka) catalytic subunit pka1 are unable to mate, fail to produce melanin or capsule, and are avirulent in animal models, whereas mutants lacking the pka regulatory subunit pkr1 overproduce capsule and are hypervirulent. because other mutations have been ob ...200414871933
investigation of the basis of virulence in serotype a strains of cryptococcus neoformans from apparently immunocompetent individuals.cryptococcus neoformans serotype a strains commonly infect immunocompromised patients to cause fungal meningitis. to understand the basis of serotype a cryptococcal infections in apparently immunocompetent patients, we tested two hypotheses: the strains were naturally occurring hypervirulent pkr1 (pka regulatory subunit) mutants, or the strains were hybrids with c. neoformans var. gattii strains that normally infect immunocompetent individuals. analysis of clinical isolates obtained from apparen ...200415150669
the first isolation of cryptococcus neoformans from eucalyptus trees in south aegean and mediterranean regions of anatolia in turkey despite taurus mountains alkalinity.eucalyptus trees are widespread in subtropical parts of turkey that have alkaline environments due to the soil structure of taurus mountains. in this study, the existence of cryptococcus neoformans in eucalyptus trees in the south aegean and mediterranean regions of anatolia, turkey, was screened between march 1998 and september 2002. only one strain of cryptococcus neoformans var. grubii (serotype a) was isolated from 1175 eucalyptus samples including debris and flowers in culture by guizotia a ...200415487319
detection of cryptococcus neoformans var. grubii in honeybee (apis mellifera) colonies.the plant flora has an important role in the ecology of cryptococcus neoformans. it is estimated that the environmental spreading and contamination of human beings with this yeast occurs via contaminated particles of plants. cultivation of canopy parts of plants in selective media is the most widely used isolation method of this yeast. cryptococcus neoformans var. grubii was isolated from honeybee colonies in eucalyptus forests but was not isolated from the places where this flora did not exist. ...200415504129
preliminary observations on the phosphatases of cryptococcus neoformans: a histochemical study. 195914417618
follow-up of epidemiological data of cryptococcosis in austria, germany and switzerland with special focus on the characterization of clinical isolates.the present survey in austria, germany and switzerland continued the survey of cryptococcosis set up by the european confederation of medical mycology (ecmm) in 1997. from 2000 to 2003 77 cases have been reported. an hiv infection is still the most important risk factor (68%). young hiv+ women from asia contributed to the increase of cryptococcosis in females. a total of 129 clinical isolates of both surveys were genotyped by pcr fingerprinting to study the prevalence of different genotypes. the ...200415601449
clinicopathologic features of an unusual outbreak of cryptococcosis in dogs, cats, ferrets, and a bird: 38 cases (january to july 2003).to determine clinical and pathologic findings associated with an outbreak of cryptococcosis in an unusual geographic location (british columbia, canada).200415626222
new pcr primer pairs specific for cryptococcus neoformans serotype a or b prepared on the basis of random amplified polymorphic dna fingerprint pattern analyses.thirty-three strains of cryptococcus neoformans were isolated from clinical specimens, including specimens from aids patients in brazil, and were classified into two serotypes; we detected 31 and 2 strains of serotypes a and b, respectively. random amplified polymorphic dna (rapd) fingerprint pattern analyses of these strains of serotypes a and b showed that the patterns were similar for strains of each serotype when three 10-mer primers were used as the rapd primers. comparative studies of the ...19999889210
cryptococcus neoformans var. grubii: separate varietal status for cryptococcus neoformans serotype a isolates.cryptococcus neoformans var. neoformans presently includes isolates which have been determined by the immunologic reactivity of their capsular polysaccharides to be serotype a and those which have been determined to be serotype d. however, recent analyses of the ura5 sequences and dna fingerprinting patterns suggest significant genetic differences between the two serotypes. therefore, we propose to recognize these genotypic distinctions, as well as previously reported phenotypic differences, by ...19999986871
characterization of the glyceraldehyde-3-phosphate dehydrogenase gene [correction of glyceraldehyde-3-phosphate gene] and the use of its promoter for heterologous expression in cryptococcus neoformans, a human pathogen.the gpd gene encoding glyceraldehyde-3-phosphate dehydrogenase was isolated from cryptococcus neoformans, a heterobasidiomycetous yeast that is pathogenic to humans. the gene contains 11 introns, differing from the conserved intron positions found in the gpd genes of basidiomycetes. the predicted amino-acid sequence of this gene is extremely similar to that reported from gpd proteins of other basidiomycetes. the promoter region of the c. neoformans gpd gene was similar to those of other basidiom ...199910352226
cryptococcemia. an analysis of 28 cases with emphasis on the clinical outcome and its etiologic agent.clinical protocols of 28 cases of cryptococcemia studied between april 1995 and november 2002 were reviewed. the varieties of cryptococcus neorformans, the underlying disease, and the severity and outcome of the disease were emphasized. most patients were immunossupressed (89.3% with aids) and cryptococcus neoformans var. grubii was the main recovered variety (92.8%). regardless of antifungal treatment, in-hospital mortality was 41% strongly associated with apache ii score, >14 (p<0.01).200415709789
cryptococcus neoformans: a sugar-coated killer with designer genes.cryptococcus neoformans has become a common central nervous system pathogen as the immunocompromised populations enlarge world-wide. this encapsulated yeast has significant advantages for the study of fungal pathogenesis and these include: (1) a clinically important human pathogen; (2) a tractable genetic system; (3) advanced molecular biology foundation; (4) understanding of several virulence phenotypes; (5) well-studied pathophysiology; and (6) robust animal models. with the use of a sequenced ...200516055314
manganese superoxide dismutase in pathogenic fungi: an issue with pathophysiological and phylogenetic involvements.manganese-containing superoxide dismutases (mnsods) are ubiquitous metalloenzymes involved in cell defence against endogenous and exogenous reactive oxygen species. in fungi, using this essential enzyme for phylogenetic analysis of pneumocystis and ganoderma genera, and of species selected among ascomycota, basidiomycota and zygomycota, provided interesting results in taxonomy and evolution. the role of mitochondrial and cytosolic mnsods was explored in some pathogenic basidiomycota yeasts (cryp ...200516055318
dna fingerprinting pattern and susceptibility to antifungal drugs in cryptococcus neoformans variety grubii isolates from barcelona city and rural environmental samples.cryptococcus neoformans var. grubii (serotype a) was isolated from 12 soil samples mixed with pigeon droppings (16.9%) from 71 soil samples in barcelona and rural areas of catalonia. c. neoformans was not isolated from indoor dust and eucalyptus debris. pcr fingerprinting was performed in 22 representative isolates and all of them corresponded to the vni pattern. susceptibility testing for the 22 isolates of c. neoformans var. grubii showed that all of them were susceptible to amphotericin b. th ...200516160762
evidence of sexual recombination among cryptococcus neoformans serotype a isolates in sub-saharan africa.the most common cause of fungal meningitis in humans, cryptococcus neoformans serotype a, is a basidiomycetous yeast with a bipolar mating system. however, the vast majority (>99.9%) of c. neoformans serotype a isolates possess only one of the two mating type alleles (matalpha). isolates with the other allele (mata) were recently discovered and proven to mate in the laboratory. it has been a mystery whether and where c. neoformans strains undergo sexual reproduction. here, we applied population ...200314665451
ugd1, encoding the cryptococcus neoformans udp-glucose dehydrogenase, is essential for growth at 37 degrees c and for capsule biosynthesis.we report the identification and disruption of the cryptococcus neoformans var. grubii ugd1 gene encoding the udp-glucose dehydrogenase, which catalyzes the conversion of udp-glucose into udp-glucuronic acid. deletion of ugd1 led to modifications in the cell wall, as revealed by changes in the sensitivity of ugd1delta cells to sodium dodecyl sulfate, nacl, and sorbitol. moreover, two of the yeast's major virulence factors-capsule biosynthesis and the ability to grow at 37 degrees c-were impaired ...200415590833
isolation of cryptococcus gattii and cryptococcus neoformans var. grubii from the flowers and bark of eucalyptus trees in india.the association of cryptococcus gattii with eucalyptus trees has been well established. here we report the isolation of both c. gattii and cryptococcus neoformans var. grubii from the flowers and bark of eucalyptus trees in india. we investigated a total of 233 samples of eucalyptus trees: 120 flowers, 81 fragments of bark, and 32 leaves. c. gattii was isolated from two samples of flowers of eucalyptus terreticornis. c. neoformans var. grubii was recovered twice from the bark of eucalyptus camal ...200516323312
virulence profile of strains of cryptococcus neoformans var. grubii evaluated by experimental infection in balb/c mice and correlation with exoenzyme activity.to evaluate the virulence profile of strains of cryptococcus neoformans var. grubii, 62 strains of this yeast were inoculated into balb/c mice. it was found that 69 % of the strains were significantly more lethal to the mice and were recovered from a higher percentage (60 %) of the organs compared with the other 31 % of the strains, which were recovered from 35 % of organs tested. those strains that provoked higher death rates were also recovered from the central nervous system at a higher rate ...200616434704
mating-type locus of cryptococcus neoformans: a step in the evolution of sex chromosomes.the sexual development and virulence of the fungal pathogen cryptococcus neoformans is controlled by a bipolar mating system determined by a single locus that exists in two alleles, alpha and a. the alpha and a mating-type alleles from two divergent varieties were cloned and sequenced. the c. neoformans mating-type locus is unique, spans >100 kb, and contains more than 20 genes. mat-encoded products include homologs of regulators of sexual development in other fungi, pheromone and pheromone rece ...200212455690
simultaneous detection and identification of candida, aspergillus, and cryptococcus species by reverse line blot hybridization.we report on a reverse line blot (rlb) assay, utilizing fungal species-specific oligonucleotide probes to hybridize with internal transcribed spacer 2 region sequences amplified using a nested panfungal pcr. reference and clinical strains of 16 candida species (116 strains), cryptococcus neoformans (five strains of cryptococcus neoformans var. neoformans, five strains of cryptococcus neoformans var. grubii, and six strains of cryptococcus gatti), and five aspergillus species (68 strains) were al ...200616517870
in vitro susceptibilities of malaysian clinical isolates of cryptococcus neoformans var. grubii and cryptococcus gattii to five antifungal drugs.the in vitro susceptibilities of malaysian clinical isolates of cryptococcus neoformans var. grubii and c . gattii to five antifungal drugs (amphotericin b, flucytosine, fluconazole, itraconazole and ketoconazole) were determined using the etest method. none of the malaysian isolates was resistant to amphotericin b and ketoconazole. isolates resistant to flucytosine, fluconazole and itraconazole were observed in this study. minimum inhibition concentrations (mics) of > or = 32 microg ml(-1) agai ...200616784448
cryptococcus neoformans var. grubii isolates recovered from persons with aids demonstrate a wide range of virulence during murine meningoencephalitis that correlates with the expression of certain virulence factors.cryptococcus neoformans is a common cause of meningoencephalitis among aids patients. several c. neoformans virulence factors have been identified, but the relative importance of particular factors is unknown. this study examined the correlation of the virulence of 18 c. neoformans var. grubii isolates from aids patients with the expression of several well-described virulence factors. the ld50 at 15 days after intracranial inoculation of icr mice was <100 c.f.u. for 22 % of isolates, 100-1000 fo ...200616849791
heat killed cells of cryptococcus neoformans var. grubii induces protective immunity in rats: immunological and histopathological parameters.different clinical parameters which included cell-mediated immune (cmi) response, were evaluated in a model of disseminated cryptococcosis in rats. the experimental animals were pretreated four days prior to their exposure to cryptococcus neoformans var. grubii with either heat killed cells of this yeastlike pathogen (hkc) or capsular polysaccharide (cps) emulsified in complete freund adjuvant (cfa). rats treated with hkc-cfa and intraperitoneally infected with c. neoformans var. grubii had sign ...200616966166
experimental systemic infection with cryptococcus neoformans var. grubii and cryptococcus gattii in normal and immunodeficient mice.cryptococcus neoformans (cn) var. grubii or cryptococcus neoformans var. neoformans infection is usually associated with immunocompromised hosts, whereas cryptococcusgattii more frequently causes disease in immunocompetent hosts. we examined the effects of immunodeficiency and glucocorticoid-induced immunosuppression on systemic murine infection induced by i.v. inoculation with these pathogens. scid and immunocompetent balb/c and c57bl/6 mice were infected with <or=107 yeast of cn var. grubii or ...200617071553
comparison of genotypes between environmental and clinical isolates of cryptococcus neoformans var. grubii based on microsatellite patterns.we applied multilocus microsatellite typing (mlmt) method to investigate the genetic relation between cryptococcus neoformans var. grubii clinical and environmental isolates in são paulo, brazil. this mlmt method includes three functional gene sequences of c. neoformans var. grubii, which are dispersed on three chromosomes. in all, 89 strains (36 clinical and 53 environmental isolates) were analyzed. of 36 clinical strains, 20 belonged to a major type of mlmt-13 (55.6%). they were mainly isolate ...201019680781
cryptococcal lipid metabolism: phospholipase b1 is implicated in transcellular metabolism of macrophage-derived lipids.cryptococci survive and replicate within macrophages and can use exogenous arachidonic acid for the production of eicosanoids. phospholipase b1 (plb1) has a putative, but uninvestigated, role in these processes. we have shown that uptake and esterification of radiolabeled arachidonic, palmitic, and oleic acids by the cryptococcus neoformans var. grubii h99 wild-type strain and its plb1 deletion mutant strain (the deltaplb1 strain) are independent of plb1, except under hyperosmolar stress. simila ...200717099081
divergence of protein kinase a catalytic subunits in cryptococcus neoformans and cryptococcus gattii illustrates evolutionary reconfiguration of a signaling cascade.gene duplication and divergence via both the loss and gain of gene activities are powerful evolutionary forces underlying the origin of new biological functions. here a comparative genetics approach was applied to examine the roles of protein kinase a (pka) catalytic subunits in three closely related varieties or sibling species of the pathogenic fungus genus cryptococcus. previous studies revealed that two pka catalytic subunits, pka1 and pka2, control virulence factor production and mating. ho ...200717189488
in-vitro antifungal activities of sulfa drugs against clinical isolates of aspergillus and cryptococcus species.in vitro susceptibilities of ten clinical isolates, including five strains of cryptococcus neoformans var. grubii and five strains of aspergillus fumigatus, were determined against nine sulfa drugs using a microdilution method. among the five tested media, minimum inhibitory concentration (mic) values were observed only in ynb medium: no detectable level mic value of less than 125 microg/ml was observed in the four remaining media against cryptococcus species. of the nine sulfa drugs, of which s ...200717287722
first case of cryptococcosis in a new species of bandicoot (bandicota indica) caused by cryptococcus neoformans var. grubii.the first case of cryptococcosis caused by cryptococcus neoformans var. grubii in a new species of bandicoot (bandicota indica) is described. the animal was trapped in a bamboo thicket in a park located in the city of jabalpur, india. on necropsy, pathological lesions were seen in the lungs and liver and c. neoformans var. grubii was isolated from the lungs, liver, kidneys, spleen and brain but not the heart or intestine. the soil of the animal's burrow and bamboo debris around it also revealed ...200717325950
disseminated, histologically confirmed cryptococcus spp infection in a domestic ferret.a 4-year-old castrated male domestic ferret from central massachusetts was evaluated for weight loss over a 1.5-month period and for 2 days of retching, diarrhea, and signs of lethargy. it had been housed indoors, with 2 other ferrets, 2 cats, and humans that lacked signs or symptoms of disease.201020367045
antifungal susceptibility of cryptococcus neoformans and cryptococcus gattii isolates from decayed wood of trunk hollows of ficus religiosa and syzygium cumini trees in north-western india.we present antifungal susceptibility data on environmental isolates of cryptococcus neoformans (serotype a, n=117) and cryptococcus gattii (serotype b, n=65) cultured from decayed wood of trunk hollows of ficus religiosa and syzygium cumini trees.200717553813
exploration of whole-genome responses of the human aids-associated yeast pathogen cryptococcus neoformans var grubii: nitric oxide stress and body temperature.cryptococcus neoformans var grubii is an opportunistic basidiomycete yeast pathogen that is a significant cause of hiv/aids-related deaths worldwide. we describe a whole-genome oligonucleotide microarray for this pathogen. these arrays have been used to elucidate the transcriptional responses of the genome to heat shock as well as to two conditions relevant to human infections: body temperature and nitric oxide (no) stress produced by the no donor dpta-nonoate. this analysis revealed an no-induc ...200717661046
ecological niche of cryptococcus neoformans var. grubii and cryptococcus gattii in decaying wood of trunk hollows of living trees in jabalpur city of central india.cryptococcus neoformans var. grubii and c. gattii were repeatedly isolated from decaying wood of trunk hollows in living trees growing in jabalpur city in central india. the isolation of c. gattii has been reported from decayed wood inside trunk hollow of tamarindus indica (15.6%), mangifera indica (2.2%), pithecolobium dulce (12.5%), syzygium cumini (14%), and one from bark of s. cumini. c. n. var. grubii was isolated from decaying wood debris of t. indica (4.4%), m. indica (13.3%), terminalia ...200717661160
cryptococcus neoformans, a fungus under stress.cryptococcus neoformans is a human fungal pathogen that survives exposure to stresses during growth in the human host, including oxidative and nitrosative stress, high temperature, hypoxia, and nutrient deprivation. there have been many genes implicated in resistance to individual stresses. notably, the catalases do not have the expected role in resistance to external oxidative stress, but specific peroxidases appear to be critical for resistance to both oxidative and nitrosative stresses. signa ...200717707685
ssk2 mitogen-activated protein kinase kinase kinase governs divergent patterns of the stress-activated hog1 signaling pathway in cryptococcus neoformans.the stress-activated p38/hog1 mitogen-activated protein kinase (mapk) pathway is structurally conserved in many diverse organisms, including fungi and mammals, and modulates myriad cellular functions. the hog1 pathway is uniquely specialized to control differentiation and virulence factors in a majority of clinical cryptococcus neoformans serotype a and d strains. here, we identified and characterized the ssk2 mapkkk that functions upstream of the mapkk pbs2 and the mapk hog1 in c. neoformans. t ...200717951522
multilocus sequence typing reveals three genetic subpopulations of cryptococcus neoformans var. grubii (serotype a), including a unique population in botswana.we applied multilocus sequence typing (mlst) to investigate the population structure and mode of reproduction of cryptococcus neoformans var. grubii (serotype a). this mlst system utilizes 12 unlinked polymorphic loci, which are dispersed on nine different chromosomes, and allows the unambiguous identification of closely related strains of serotype a. we compared mlst analyses with the conventional genotyping method of detecting amplified fragment length polymorphisms (aflps), and there was exce ...200616322524
cryptococcosis in apparently immunocompetent patients.few reports have described the clinical and microbiological features of cryptococcosis in immunocompetent patients.200616504989
isolation of cryptococcus neoformans var. grubii (serotype a) from pigeon droppings in seoul, korea.seventy-two pigeon dropping samples were collected from 26 different localities in seoul and investigated for the occurrence of cryptococcus neoformans. seventeen samples from 8 different localities were found to be positive for c. neoformans. all isolates were obtained from withered pigeon droppings. identification and serotyping of the isolates were determined by means of serological testing and dna fingerprinting. all isolates belonged to c. neoformans var. grubbi (serotype a).200516273041
zoonotic transmission of cryptococcus neoformans from a magpie to an immunocompetent patient.we report a case of cryptococcal meningitis in an immunocompetent female patient with exposure to a pet magpie (pica pica). genetically indistinguishable isolates were cultured from the cerebrospinal fluid of the patient and excreta of the bird. our data strongly suggest zoonotic transmission of cryptococcus neoformans var. grubii from a magpie to this patient.200515788009
isolates of cryptococcus neoformans from infected animals reveal genetic exchange in unisexual, alpha mating type populations.sexual reproduction and genetic exchange are important for the evolution of fungal pathogens and for producing potentially infective spores. studies to determine whether sex occurs in the pathogenic yeast cryptococcus neoformans var. grubii have produced enigmatic results, however: basidiospores are the most likely infective propagules, and clinical isolates are fertile and genetically diverse, consistent with a sexual species, but almost all populations examined consist of a single mating type ...200818552280
multilocus microsatellite typing for cryptococcus neoformans var. grubii.fifteen randomly selected microsatellites (simple sequence repeats; ssrs), from the h99 cryptococcus neoformans var. grubii (serotype a) genome, were sequenced, characterized and applied to sequence 87 clinical and environmental c. neoformans var. grubii isolates from 12 different countries based on multilocus microsatellite typing (mlmt). among the 15 ssr loci, three (designated cng1, cng2 and cng3) were polymorphic, while the remaining 12 ssr loci showed no variations. the specific pcr primers ...200818608927
spinal cryptococcoma in an immunocompetent cat.this report describes an unusual case of primary cryptococcoma in the proximal thoracic spinal cord of an 11-year-old immunocompetent cat from a farm on which there were large numbers of pigeons. this animal was referred for examination with progressive paralysis and shown to be free from feline immunodeficiency virus, feline leukaemia virus, feline coronavirus and toxoplasma gondii. it died 2 months later. at necropsy, the only lesion detected was a malacic area, 4cm in length, in the spinal co ...200818783789
epidemiology and management of cryptococcal meningitis: developments and challenges.the significance of cryptococcal infection as a cause of human disease has dramatically evolved in recent years. the objective of this study was to outline the worldwide significance of cryptococcosis and review developments in the management of cryptococcal meningitis. cryptococcus neoformans var. grubii remains an important cause of disease, particularly in hosts with acquired immunosuppression. cryptococcus gattii, on the other hand, infects hosts with seemingly normal immune systems and a re ...200818312157
diploids in the cryptococcus neoformans serotype a population homozygous for the alpha mating type originate via unisexual mating.the ubiquitous environmental human pathogen cryptococcus neoformans is traditionally considered a haploid fungus with a bipolar mating system. in nature, the alpha mating type is overwhelmingly predominant over a. how genetic diversity is generated and maintained by this heterothallic fungus in a largely unisexual alpha population is unclear. recently it was discovered that c. neoformans can undergo same-sex mating under laboratory conditions generating both diploid intermediates and haploid rec ...200919180236
cryptococcus neoformans serotype a and cryptococcus gattii serotype b isolates differ in their susceptibilities to fluconazole and voriconazole.this study presents antifungal susceptibility data for environmental isolates of cryptococcus neoformans serotype a (n=32) and cryptococcus gattii serotype b (n=18) to fluconazole and voriconazole employing disc diffusion and etest methods. the disc diffusion test was performed on mueller-hinton agar as recommended by the clinical and laboratory standards institute (clsi). for comparison, the disc diffusion test and etest were also performed on rpmi-1640 agar supplemented with 2% glucose. the pl ...200919195846
most environmental isolates of cryptococcus neoformans var. grubii (serotype a) are not lethal for mice.most cases of cryptococcosis are caused by cryptococcus neoformans var. grubii (serotype a), which is widespread in the environment, where it is primarily associated with pigeon excreta. a number of molecular epidemiological studies indicate that many environmental and clinical isolates of serotype a are indistinguishable. however, the murine virulence of environmental strains of c. neoformans has not been thoroughly evaluated. we used the murine intranasal model of cryptococcosis to compare the ...200919487475
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