Navegando por Palavras-chave "Cryptococcus"
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- ItemSomente MetadadadosAssociação saprobiótica de Cryptococcus Laurentii com Eucalyptus Camaldulensis(Universidade Federal de São Paulo (UNIFESP), 1998) Costa, Emerson Ferreira da [UNIFESP]; Gompertz, Olga Fischman [UNIFESP]Durante o periodo de novembro de 1993 a julho de 1995 foram coletadas noventa e cinco amostras de restos vegetais sob as copas de Eucalyptus camaldulensis plantados no estado de Sergipe, Nordeste do Brasil, objetivando o isolamento de leveduras do genero Cryptococcus. C. laurentii foi isolado repetidamente de amostras coletadas sob as copas das arvores. A continua positividade sugere colonizacao destes microambientes e indicam a ocorrencia saprobiotica de C. laurentii relacionada a E. camaldulensis. Botoes florais e folhas verdes, tambem examinados, foram negativos. Oleos essenciais extraidos de E. camaldulensis mostraram capacidade para inibir o crescimento de C. laurentii e C. neoformans variedades neoformans e gattii. Estes achados reforcam a possibilidade de associacao saprobiotica entre C. laurentii e E. camaldulensis
- ItemAcesso aberto (Open Access)Caracterização clínica e genotípica da Criptococose em pacientes submetidos a transplante renal(Universidade Federal de São Paulo (UNIFESP), 2019-03-28) Silva, Vinicius Ponzio Da [UNIFESP]; Colombo, Arnaldo Lopes [UNIFESP]; http://lattes.cnpq.br/4512261018429681; http://lattes.cnpq.br/7842748738879723; Universidade Federal de São Paulo (UNIFESP)Cryptococcosis is the second most common invasive fungal infections in renal transplant recipients and Brazil has substantial genotypic diversity in C. neoformans/C. gattii species complexes. Clinical outcome of cryptococcosis, graft outcome after treatment and the impact of the molecular type of the yeasts in renal transplant recipients have been scarcely studied, especially in less resource-available countries. Article 1: The purpose of this study was to assess renal allograft dysfunction and its impact on renal transplant recipients with cryptococcosis receiving antifungal therapy. Data from 47 renal transplant recipients were retrospectively collected at a single institution during a period of 13 years. Graft dysfunction, graft loss and mortality rates were evaluated. Predictors of mortality and graft loss were estimated. A total of 38 (97.4%) patients treated with amphotericin B deoxycholate showed graft dysfunction and eight (18.2%) had kidney graft loss. Graft loss within 30 days after cryptococcosis onset was significantly associated with disseminated infection, greater baseline creatinine levels and graft dysfunction concomitant to amphotericin B deoxycholate therapy and an additional renal injury condition. The 30-day mortality rate was 19.2% and it was significantly associated with disseminated and pulmonary infections, somnolence at admission, high cerebrospinal fluid opening pressure, positive cerebrospinal fluid India ink, creatinine levels greater than 2.0 mg/dL at admission, graft dysfunction in patients treated with amphotericin B deoxycholate and an additional renal injury condition and graft loss within 30 days. The rate of graft loss rate was high, most frequently in patients with concomitant renal injury conditions. Therefore, the clinical focus should be on the use of less nephrotoxic lipid formulations of amphotericin B in this specific population. Article 2:The purpose of this study was to characterize the molecular types of C. neoformans/C. gattii species complexes and assess the factors associated with clinical outcome of cryptococcosis in renal transplant recipients in Brazil. We examined the genotypic diversity and fluconazole susceptibility pattern of 82 C. neoformans and C. gattii isolates from 60 renal transplant recipients. Clinical characteristics of the patients and prognostic factors were analyzed. A total of 72 (87.8%) isolates were C. neoformans and 10 (12.2%) were C. gattii. VNI was the most common molecular type (40 cases; 66.7%), followed by VNII (9 cases; 15%), VGII (6 cases; 10%), VNB (4 cases; 6.7%) and VNI/II (1 case; 1.7%). The isolates showed a high genetic diversity in the haplotype network and six new sequence types were described, most of them for VNB. There was a bias towards skin involvement in the non-VNI population (P = 0.012). VGII isolates exhibited higher fluconazole minimum inhibitory concentrations compared to C. neoformans isolates (P = 0.008). The 30-day mortality rate was 38.3% and it was significantly associated with fungemia and absence of headache. Furthermore, patients infected with VGII had a particularly high mortality rate at 90 days (66.7%). A variety of molecular types produces disease in renal transplant recipients in Brazil and highlighted by VGII and VNB. Cryptococcosis in renal transplant recipients is associated with high mortality in less-available resource health care settings. We report the clinical appearance and impact of the molecular type, fluconazole susceptibility of the isolates, and certain clinical characteristics on the patient outcome in this high risk population.
- ItemAcesso aberto (Open Access)Lymphocyte transformation assay for C neoformans antigen is not reliable for detecting cellular impairment in patients with Neurocryptococcosis(Biomed Central Ltd, 2012-10-30) Rocha, Katya C.; Pinhal, Cinthia; Cavalcanti, Sonia; Vidal, Monica S. M.; Toscano, Matheus; Moraes-Vasconcelos, Dewton; Duarte, Alberto J. S.; Fonseca, Fernando Luiz Affonso [UNIFESP]; Abreu, Luiz Carlos de; Valenti, Vitor E.; Grumach, Anete S. G.; Universidade de São Paulo (USP); Fac Med ABC; Universidade Federal de São Paulo (UNIFESP); Univ Estadual PaulistaBackground: Cryptococcus neoformans causes meningitis and disseminated infection in healthy individuals, but more commonly in hosts with defective immune responses. Cell-mediated immunity is an important component of the immune response to a great variety of infections, including yeast infections. We aimed to evaluate a specific lymphocyte transformation assay to Cryptococcus neoformans in order to identify immunodeficiency associated to neurocryptococcosis (NCC) as primary cause of the mycosis.Methods: Healthy volunteers, poultry growers, and HIV-seronegative patients with neurocryptococcosis were tested for cellular immune response. Cryptococcal meningitis was diagnosed by India ink staining of cerebrospinal fluid and cryptococcal antigen test (Immunomycol-Inc, SP, Brazil). Isolated peripheral blood mononuclear cells were stimulated with C. neoformans antigen, C. albicans antigen, and pokeweed mitogen. the amount of H-3-thymidine incorporated was assessed, and the results were expressed as stimulation index (SI) and log SI, sensitivity, specificity, and cut-off value (receiver operating characteristics curve). We applied unpaired Student t tests to compare data and considered significant differences for p<0.05.Results: the lymphotoxin alpha showed a low capacity with all the stimuli for classifying patients as responders and non-responders. Lymphotoxin alpha stimulated by heated-killed antigen from patients with neurocryptococcosis was not affected by TCD4+ cell count, and the intensity of response did not correlate with the clinical evolution of neurocryptococcosis.Conclusion: Response to lymphocyte transformation assay should be analyzed based on a normal range and using more than one stimulator. the use of a cut-off value to classify patients with neurocryptococcosis is inadequate. Statistical analysis should be based on the log transformation of SI. A more purified antigen for evaluating specific response to C. neoformans is needed.
- ItemAcesso aberto (Open Access)Tracing Genetic Exchange and Biogeography of Cryptococcus neoformans var. grubii at the Global Population Level(Genetics Society America, 2017) Rhodes, Johanna; Desjardins, Christopher A.; Sykes, Sean M.; Beale, Mathew A.; Vanhove, Mathieu; Sakthikumar, Sharadha; Chen, Yuan; Gujja, Sharvari; Saif, Sakina; Chowdhary, Anuradha; Lawson, Daniel John; Ponzio, Vinicius [UNIFESP]; Colombo, Arnaldo Lopes [UNIFESP]; Meyer, Wieland; Engelthaler, David M.; Hagen, Ferry; Teresa Illnait-Zaragozi, Maria; Alanio, Alexandre; Vreulink, Jo-Marie; Heitman, Joseph; Perfect, John R.; Litvintseva, Anastasia P.; Bicanic, Tihana; Harrison, Thomas S.; Fisher, Matthew C.; Cuomo, Christina A.Cryptococcus neoformans var. grubii is the causative agent of cryptococcal meningitis, a significant source of mortality in immunocompromised individuals, typically human immunodeficiency virus/AIDS patients from developing countries. Despite the worldwide emergence of this ubiquitous infection, little is known about the global molecular epidemiology of this fungal pathogen. Here we sequence the genomes of 188 diverse isolates and characterize the major subdivisions, their relative diversity, and the level of genetic exchange between them. While most isolates of C. neoformans var. grubii belong to one of three major lineages (VNI, VNII, and VNB), some haploid isolates show hybrid ancestry including some that appear to have recently interbred, based on the detection of large blocks of each ancestry across each chromosome. Many isolates display evidence of aneuploidy, which was detected for all chromosomes. In diploid isolates of C. neoformans var. grubii (serotype AA) and of hybrids with C. neoformans var. neoformans (serotype AD) such aneuploidies have resulted in loss of heterozygosity, where a chromosomal region is represented by the genotype of only one parental isolate. Phylogenetic and population genomic analyses of isolates from Brazil reveal that the previously "African" VNB lineage occurs naturally in the South American environment. This suggests migration of the VNB lineage between Africa and South America prior to its diversification, supported by finding ancestral recombination events between isolates from different lineages and regions. The results provide evidence of substantial population structure, with all lineages showing multi-continental distributions