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PubMed2003

[Antifungal activity of Caryocar brasiliensis (Caryocaraceae) against Cryptococcus neoformans].

The widespread occurrence of cryptococcosis mainly in immunocompromised patients and the side effects of available drugs which are effective against this mycosis have led investigators to search for new antimycotic agents. Caryocar brasiliensis derived compounds were investigated against Cryptococcus neoformans using the agar dilution method. Based on MIC values, the best results were obtained with a concentration of < 250 g/mL of cuticular waxes of the Caryocar brasiliensis leaf collected during the dry period (170.8mm of precipitation) which inhibited the growth of 91.3% (21/23) Cryptococcus neoformans isolates.

Antifungal Agents↗
PubMed1995

Detection of Cryptococcus neoformans in bronchial lavage cytology: report of four cases.

Four cases of pulmonary cryptococcosis were diagnosed by cytological detection of Cryptococcus neoformans in bronchial lavage. Three patients had underlying diseases, but not HIV infection. The chest X-rays showed 2 patients with nodular lesions and 2 with cavitary lesions. The cryptococcal antigen in the serum was positive in all four patients. In the cytology of bronchial lavage, Cryptococcus neoformans was detected after period-acid-Schiff (PAS) staining and was cultured in Sabouraud-dextrose agar. The cytology of bronchial lavage is useful for the rapid diagnosis of pulmonary cryptococcosis.

Adult↗
PubMed2004

Cryptococcus paraflavus sp. nov. (Tremellales), isolated from steppe plants in Russia.

Three strains related to Cryptococcus flavus were isolated from plants collected in the Prioksko-terrasny biosphere reserve (Russia). Physiological characterization, mycocinotyping, sequencing of the D1/D2 domain of the 26S rDNA and the ITS region revealed their separate taxonomic position. The name Cryptococcus paraflavus is proposed to accommodate these isolates (type strain VKM Y-2923).

Cryptococcus↗
PubMed2006

In the absence of reactive oxygen species, T cells default to a Th1 phenotype and mediate protection against pulmonary Cryptococcus neoformans infection.

In recent years, the prevalence of invasive fungal infections has increased, attributed mostly to the rising population of immunocompromised individuals. Cryptococcus neoformans has been one of the most devastating, with an estimated 6-8% of AIDS-infected patients succumbing to Cryptococcus-associated meningitis. Reactive oxygen species (ROS) are potent antimicrobial agents but also play a significant role in regulating immune cell phenotype, but cause immunopathology when produced in excess. We now show that mice lacking phagocyte NADPH oxidase have heightened macrophage and Th1 responses and improved pathogen containment within pulmonary granulomatous lesions. Consequently, dissemination of this fungus to the brain is diminished, an effect that is independent of IL-12. Similar results are described using the metalloporphyrin antioxidant manganese(III) tetrakis(N-ethyl pyridinium-2-yl)porphyrin, which also promoted a protective Th1 response and reduced dissemination to the brain. These findings are in sharp contrast to the protective potential of ROS against other fungal pathogens, and highlight the pivotal role that ROS can fulfill in shaping the profile of the host's immune response.

Animals↗
PubMed2000

Evidence of zoonotic transmission of Cryptococcus neoformans from a pet cockatoo to an immunocompromised patient.

BACKGROUND: Although cryptococcosis has been associated with birds for almost 50 years, point sources for infection have not been identified. OBJECTIVE: To document zoonotic transmission of Cryptococcus neoformans. DESIGN: Case report. SETTING: A home in Boston, Massachusetts. PATIENT: A 72-year-old woman who received a diagnosis of cryptococcal meningitis in November 1998. The patient, who had been taking immunosuppressant drugs since undergoing renal transplantation in 1989, owned a pet cockatoo. MEASUREMENTS: Cryptococcus neoformans was isolated from the feces of the cockatoo. Isolates from excreta and from the patient were compared by using biochemical profiles, monoclonal antibody binding patterns, restriction fragment length polymorphism analysis, and karyotyping. RESULTS: The isolates from the patient and the cockatoo had identical biochemical profiles, the same monoclonal antibody immunofluorescence patterns, and indistinguishable patterns on restriction fragment length polymorphism analysis and karyotyping. CONCLUSIONS: The indistinguishable patient and cockatoo isolates strongly suggest that the patient's infection resulted from exposure to aerosolized cockatoo excreta. Although the incidence of cryptococcal infection due to such exposure is unknown, it may be prudent to advise immunocompromised patients to avoid pet birds and avian excreta.

Aged↗
PubMed1997

Cryptococcus neoformans var neoformans isolated from droppings of captive birds in Nigeria.

The yeast, Cryptococcus neoformans, was found in apparently healthy birds at the Jos Wildlife Park and Zoo in Jos, Nigeria. Cryptococcus neoformans var neoformans was isolated from feces of four captive bird species. Five isolates belonged to serotype A while two were serotype D. Serotype A of C. neoformans was isolated from a white face duck (Dendrocygna viduata), eagle owl (Bubo africanus cinerascene) and peacock (Pavo cristatus). The other two (serotype D), were isolated from a spotted eagle owl.

Animals↗
PubMed2006

Cryptococcus gattii in wildlife of Vancouver Island, British Columbia, Canada.

Although Cryptococcus gattii has emerged as an important pathogen of humans and domestic animals on Vancouver Island, Canada since 1999; its distribution in regional wildlife species is largely unknown. Opportunistic sampling methods were employed to obtain nasal swabs for fungal culture from wild mammal species residing within the coastal Douglas fir biogeoclimatic zone on the southeast coast of the island. Samples were collected from 91 animals representing 14 species. Cryptococcus gattii was isolated from the nasal swabs of two eastern gray squirrels (Sciurus carolinensis) trapped in Duncan, British Columbia. The relative proportion of nasal colonization in wild mammal species is consistent with findings in domestic animals, suggesting that animals may be good indicators of environmental organisms.

Animals↗
PubMed2000

[Monitoring of the cryptococcus count in the cerebrospinal fluid with negative cultures in two cases of serious cryptococcal meningitis].

We monitored the cryptococcus count in the cerebrospinal fluid(CSF) using the filter technique in two cases of serious cryptococcal meningitis during the course of treatment with antifungal agents. Lumbar puncture was performed once a week, and 1 ml of CSF was filtered through a Millipore filter(5.0-micron pore for cells), followed by staining of the filters with Alcian blue. All of the cryptococci on the filter were counted under a light microscope at a magnification of x 100. More than 500/ml and 2,000/ml of cryptococci were still observed in the CFS in Cases 1 and 2, respectively, in whom CFS cultures for Cryptococcus neoformans became negative after 4 weeks of treatment. Even though the treatment with antifungal agents were continued in these cases, cryptococci could still be observed for 5 weeks and 60 weeks on the filter preparations of Cases 1 and 2, respectively, after the CSF cultures became negative. The cryptococcal antigen could also be detected in the CSF during the positive filter preparations in these cases. At autopsy in Case 2, patchy lepromeningeal inflammatory lesions with the characteristic capsules of cryptococci were observed in the subarachnoid space. These observations suggest that cryptococci, which persisted in the CSF despite the negative cultures, were responsible for the lesions in the subarachnoid space and protracted clinical course in the two cases of cryptococcal meningitis.

Aged↗
PubMed2000

[Fourier transform infrared spectroscopy, molecular biologic methods and antimyocotic susceptibility patterns for identification and differentiation of cryptococcus species].

Molecular biological methods as well as the FTIR method allows the rapid, reliable and reproducible determination and identification of Cryptococcus species from human, veterinary and environmental origin and their serovars. The results obtained by FTIR could be verified by the molecular methods. In addition, with the PCR and FTIR fingerprinting methods it is possible to distinctly group the serovars and differentiate the different Cryptococcus strains.

Animals↗
PubMed2001

Ventriculitis due to Cryptococcus uniguttulatus.

Infections due to non-neoformans cryptococci are rare. We report the first case of a human infection caused by Cryptococcus uniguttulatus. Ventriculitis caused by this organism developed in a 65-year-old woman who had had repair of an internal carotid aneurysm. In vitro sensitivity testing showed the Cryptococcus species sensitive to amphotericin B and itraconazole. Treatment with amphotericin led to resolution of the infection.

Aged↗
PubMed2003

Phenotyping of Cryptococcus neoformans strains in Bergamo, Italy (1985-2000).

Cryptococcus neoformans is the cause of the most common life-threatening fungal infection in patients with AIDS. Thirty strains of C. neoformans were collected from inpatients and typied evaluating activity, morphotyping, serotyping, chemosensitivity and adhesivity. Cryptococcus neoformans strains showed different aspectotype profile, the sole presence of serotypes A and D, good susceptibility to azoles and Amphotericin B. Phenotypic epidemiologic markers can be used: characterization of clinical strains excludes a common source.

Adult↗
PubMedDate not supplied

[A new basidiomycetous yeast species, Cryptococcus mycelialis, related to Holtermannia Saccardo et Traverso].

A new species of the genus Cryptococcus, Cr. mycelialis (the type strain VKM Y-2863), is described based on the taxonomic study of four strains isolated from the soil and plant samples collected on the South Georgia and East Falkland islands. This species differs from the known Cryptococcus species in its ability to form a true monokaryotic mycelium with pseudoclamp connections and haustoria. The species can be distinguished from the phylogenetically related and phenotypically similar species Holtermannia corniformis and Cr. nyarrowii by some assimilatory reactions, maximum growth temperature, and sensitivity to mycocins.

Atlantic Islands↗
PubMed2004

Resistance to Cryptococcus neoformans infection in the absence of CD4+ T cells.

Previous studies of Cryptococcus neoformans infection have revealed a role for CD4+ T cells and CD8+ T cells in anticryptococcal resistance in the lungs, but such a role has been revealed only for CD4+ T cells in the brains of experimentally infected mice. In this study, we found that mice genetically engineered to lack CD4+ T cells could be successfully vaccinated to express resistance to a rechallenge with Cryptococcus neoformans, provided the challenge dose was kept to lower than 1000 organisms per mouse. The challenge infection was uniformly lethal for unvaccinated control mice. Depletion of CD8+ T cells weakened this resistance to re-challenge: both naïve and vaccinated mice that were treated with antibody raised against CD8+ T cells died significantly earlier than did mice that received an irrelevant control antibody. In vitro, purified CD8+ T cells taken from draining lymph nodes of antigen-experienced mice were less efficient than were identically prepared CD4+ T cells at stimulating the cells of a transformed microglial cell line to inhibit C. neoformans proliferation, possibly mirroring the inferiority of CD8+ T-cell-mediated protection observed in vivo. RNase protection assays showed similar IFN-gamma mRNA levels in both lymphocyte subsets. Class II major histocompatibility antigen expression was up-regulated strikingly on microglia cultured with IFN-gamma, but class I expression was less dramatically affected. Therefore microglial cell interaction may be more greatly enhanced with CD4+ cells than with CD8+ cells.

Animals↗
PubMedDate not supplied

Occurrence and significance of Cryptococcus neoformans in vegetables and fruits.

Cryptococcus neoformans was isolated from three of 437 (0.6%) samples of a wide variety of vegetables collected from a number of markets in Delhi. The vegetables yielding C. neoformans were tomato, Lycopersicon esculentum (1/70), 'vegetable sponge', Luffa cylindrica (1/56) and brinjal, Solanum melongena (1/55). Only solitary samples of these three vegetables were found to be positive. In vitro studies at 25 degrees C revealed that a reference C. neoformans isolate readily colonized, as did Candida albicans and Candida viswanathii (controls), sterilized slices of almost all the test vegetables and fruits (cut or uncut surface) which included tomato, 'vegetable sponge', brinjal, potato, carrot, radish, apple, guava, pineapple, pear, papaya, banana and mango. Sterilized juices of the same vegetables and fruits also supported adequate growth of the reference C. neoformans isolate as well as of C. albicans and C. viswanathii. However, the growth of C. neoformans on the afore-mentioned vegetables and fruits was rapidly masked by miscellaneous molds and bacteria if the test samples had not been sterilized prior to inoculation. Cryptococcus neoformans was not found in any of the 275 fruit samples investigated from the same markets. The results indicate that vegetables and fruits are unsuitable as natural habitats for C. neoformans although it may be sporadically isolated from these sources.

Cryptococcosis↗
PubMed2005

Anti-glucuronoxylomannan IgG1 specific antibodies production in Cryptococcus neoformans resistant mice.

BACKGROUND: Cryptococcus neoformans is a widely disseminated fungus shown to be responsible for infections in individuals with impaired cell mediated immunity, such as patients with human immunodeficiency virus (HIV). Cryptococcus neoformans has a polysaccharide capsule composed of glucuronoxylomannan (GXM), which acts as a major virulence factor and is considered to be a thymus independent type-2 antigen (TI-2). OBJECTIVE: In the current study, the production kinetics were evaluated for IgG subclasses specific for GXM, and assessed with the cross reactive antibodies to Streptococcus pneumoniae polysaccharide. In addition, spleen B cell subpopulations were quantified in murine models of cryptococcosis with different susceptibilities to the infection. MATERIALS AND METHODS: Antibodies were detected by ELISA at different time intervals after C. neoformans infection in moderately resistant (Balb/c), highly resistant (CBA/j) and susceptible (C57BL/6) mouse strains. B cells subpopulations were determined by flow cytometry analysis. RESULTS: Early production of IgG1, described as protector antibodies, coincided with a decrease of the number of C. neoformans colony forming units in the lungs. Polysaccharide cross-reactive antibodies were detected in each of the three mouse strains. Antibody titers were highest in the susceptible strain (C57BL/6), a strain which also showed the highest proportion of splenic CD5+ B lymphocytes. In contrast, CBA/J mice showed the highest levels of CD43+ B. CONCLUSIONS: These findings suggest that IgG1 antibodies specific for GXM, are implicated in host protection against C. neoformans infection and may be regulated by CD43+ cells. They also suggest that cross reactivity antibodies are not important in the protection against C. neoformans infection.

Animals↗
PubMed2005

[Isolation of Cryptococcus gattii serotype B from detritus of Eucalyptus trees in Colombia].

INTRODUCTION: Cryptococcus gattii serotype B has been associated with several species of trees in tropical and subtropical regions. Serotype B has been found to be the second most frequently isolated from patients in Colombia, but it has not been isolated from the environment. Therefore, a study was designed to sample plant material from a forest in the province of Cundinamarca, with the aim of establishing the presence and distribution of the C. neoformans complex, specially serotype B. In addition, isolates were evaluated for several phenotypic characteristics associated with virulence. METHODOLOGY: During February and March, 2003, 4 separate sample collections were made. One hundred sixty-seven samples were collected from detritus of eucalyptus and 28 samples from other species of trees. All were processed using the conventional procedure and plated on selective media. The following parameters were measured: cellular and capsular sizes in the filtrates, growth at 37 degrees C, virulence in a mouse animal model system, and mating type as detected by PCR. RESULTS: Cryptococcus gattii serotype B was isolated from 46 eucalyptus samples (27.5%). The cellular size in the filtrates ranged from 3.10 to 4.15 microm and the capsular size from 0.30 and 0.46 microm. The 46 isolates grew at 37 degrees C, but none of them caused the death in the animals during 70-day observation period. All isolates were of mating type a. CONCLUSIONS: This constitutes the first report of the isolation of serotype B, mating type a, from eucalyptus detritus in Colombia.

Animals↗
PubMed2006

Detection of Cryptococcus neoformans in bird excreta.

We evaluated 14 samples of bird excreta from pigeons, parrots, open billed storks and crows obtained from thirteen places in Bangkok and nearby areas between April and July 2004. These bird excreta were examined for Cryptococcus neoformans by direct plating method to inspect their ability to grow at 37 degrees C. Capsule production was examined by Indian ink preparation. They were also tested for urease and phenoloxidase enzymes. Cryptococcus neoformans var neoformans was recovered from pigeon excreta in 9.09%. This implies those having impaired immunity may get this fungus from the environment.

Animals↗