Fisetin as a promising antifungal agent against Cryptocococcus neoformans species complex.

AIMS: The aim of this study was to investigate the mechanisms of action of fisetin, a flavonol with antifungal activity previously evaluated against the Cryptococcus neoformans species complex. METHODS AND RESULTS: Ergosterol content and flow cytometry analysis were determined for the C. neoformans species complex in the presence of fisetin and ultrastructural analysis of morphology was performed on Cryptococcus gattii and C. neoformans. Decrease in the total cellular ergosterol content after exposure to fisetin ranged from 25·4% after exposure to 128 µg ml(-1) to 21·6% after exposure to 64 µg ml(-1) of fisetin compared with the control (without fisetin). The fisetin effects obtained with flow cytometry showed metabolic impairment, and alterations in its normal morphology caused by fisetin in C. neoformans cells were verified using scanning electron microscopy. CONCLUSIONS: Fisetin is a compound that acts in the biosynthesis of ergosterol. Flow cytometry showed that fisetin reduced viability of the metabolically active cells of C. gattii, while morphological changes explain the action of fisetin in inhibiting growth of these fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: This study supports the idea that fisetin may represent a good starting point for the development of future therapeutic substances for cryptococcosis.

Application of five prognostic survival scores to primary myelofibrosis in 62 Brazilian patients.

Primary myelofibrosis (PM) is a Philadelphia-negative clonal hematopoietic stem cell disorder characterized by intense reactive changes of bone marrow stroma with collagen fibrosis, osteosclerosis and angiogenesis. PM usually affects elderly people, and approximately half of the patients present JAK2V617F mutation. PM clinical course varies from 1 to 30 years, evolving from asymptomatic into progressive bone marrow failure, symptomatic splenomegaly or acute leukemia in 10-20 % of cases. PM risk stratification is based on parameters predicting survival, and several attempts have been made to identify clinical and laboratory features that could predict PM patient survival. This study applied five prognostic scores: Dupriez, Cervantes, Mayo, IPSS and DIPSS-Plus in 62 Brazilians patients from three centers, and compared their relevance and clinical usefulness considering the scores' parameters, fibrosis, JAK2V617F mutation, splenomegaly, hepatomegaly and treatment. According to the Cervantes, Dupriez and Mayo scores, most patients were stratified into low-risk group. However, when IPSS and DIPSS-Plus were applied, most patients were classified into an intermediate range, being low risk in only 11 and 13 % of patients, respectively. Overall survival at 4 years was 84 %. The Cervantes score was the only one that remained significantly associated with survival in a multivariate analysis. In conclusion, the Cervantes score remains important to the prognostication of PM.

Antifungal susceptibility patterns of yeasts and filamentous fungi isolated from nail infection.

BACKGROUND: Onychomycosis is the nail infection caused by a wide spectrum of fungi species, including yeasts, dermatophytes and filamentous fungi non-dermatophytes (FFND). This fungal infection represents an important medical problem because it involves the patient's life quality. OBJECTIVE: The aim was to isolate and identify the fungal agents of onychomycosis, and to determine the in vitro susceptibility to antifungal agents. METHODS: During the period of March 2008 to March 2009, 114 patients clinically suspected of having onychomycosis were examined. Demographic data, mainly age and gender were obtained from each patient. The nail samples collected (136) were submitted to direct examination with potassium hydroxide 20% and grown on Sabouraud dextrose agar. The in vitro antifungal susceptibility testing was performed according to the method of broth microdilution, recommended by the Clinical Laboratory Standards Institute (CLSI). RESULTS: Onychomycosis was observed in 95 (83.3%) patients, including 16 men (16.8%) and 79 women (83.2%), with mean age of 48.1 years. Candida parapsilosis, Trichophyton rubrum and Fusarium spp were the fungi most frequently isolated. The most of the isolated yeasts showed susceptibility to antifungal agents studied. Among filamentous fungi, high MIC values to itraconazole were found for T. rubrum and T. mentagrophytes, while Fusarium spp showed decreased susceptibility to itraconazole and voriconazole. CONCLUSION: C. parapsilosis was the most common fungal species isolated from patients with onychomycosis. The different response obtained by in vitro susceptibility testing to drugs shows the importance of these methods to assist clinicians in choosing the best therapeutic option.

Morphocytochemical, immunohistochemical and ultrastructural characterization of the head kidney of fat snook Centropomus parallelus.

This study characterized the structure and the morphocytochemical, immunohistochemical and ultrastructural aspects of the head kidney (HK) of the fat snook Centropomus parallelus. The HK is enclosed by a thin capsule of connective tissue, from which fine trabeculae originate and branch into the interior of organ. In the parenchyma, there are aggregates of lymphoid cells containing populations of lymphocytes T immunopositive for CDRO45, in a nodular arrangement, around blood vessels and melano-macrophage centres. Among the cells that constituted these aggregates and surrounded them, were macrophages and monocytes, and their precursors, with strong immunopositivity for CD68, along with cells of the granulocytic lineage in various phases of maturation positive for lysozyme and PAS. Macrophages and chromaffin and interrenal cells are also present. Ultrastructurally, the HK comprises a reticulum-endothelial stroma consisting of endothelial cells, reticulocytes of the fibroblast type and macrophage type and a parenchyma with increased cellularity, principally blood cells of the erythrocytic, granulocytic, lymphocytic, monocytic and thrombocytic series.

Epidemiological and mycological data of onychomycosis in Goiania, Brazil.

Onychomycosis defined as fungal infection of the nail represents more than 50% of all onychopathies. Epidemiological studies have shown that this mycosis is worldwide in occurrence, but with geographical variation in distribution. The direct microscopy and culture of the nail samples were performed to identify the causative agent. Out of 2273 patients with nail infection examined between January 2000 and December 2004 in Goiania, state of Goias, Brazil, diagnosis of onychomycosis was confirmed in 1282 cases, with dermatophytes and Candida species being the most common aetiological agents isolated. Dermatophyte onychomycosis was more common in toenails than in fingernails, while onychomycosis caused by yeast had a similar frequency in both toenails and fingernails. Among the species identified, Candida albicans was responsible for 492 cases (38.4%) of onychomycosis, Trichophyton rubrum was found in 327 cases (25.6%) and Trichophyton mentagrophytes in 258 cases (20.1%). Other fungi isolated from nail infections included Aspergillus sp., Trichosporon sp., Geotrichum sp. and Fusarium sp. In our study, yeast of the genus Candida were the dominant cause of onychomycosis in women and dermatophytes were the principal cause of this condition in men.

Molecular typing and antifungal susceptibility of clinical and environmental Cryptococcus neoformans species complex isolates in Goiania, Brazil.

A total of 124 Cryptococcus isolates, including 84 clinical strains obtained from cerebrospinal fluid from AIDS patients and 40 environmental isolates from pigeon excreta and from Eucalyptus trees, were studied. The varieties, serotypes, phospholipase activity and molecular profile of these isolates were determined. Cryptococcus neoformans var. grubii serotype A was identified in 120 isolates and Cryptococcus gattii serotype B in four isolates. The clinical isolates showed higher phospholipase activity than environmental isolates. Similar patterns of in vitro susceptibility to amphotericin B, fluconazole, itraconazole and voriconazole and no resistance were found for all isolates. Molecular type VNI (C. neoformans var. grubii) was recovered in 80 clinical and 40 environmental isolates while the type VGIII (C. gattii) was found in four clinical isolates. This study demonstrated for the first time the molecular types of clinical and environmental Cryptococcus isolates in the midwest Brazil region.

Association of loss of heterozygosity with cytogenetic abnormalities in acute myeloid leukemia and myelodysplastic syndrome.

Deletions on chromosomes 5 and 7 are frequently seen in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). It is assumed that these deletions indicate loss of tumor suppressor genes on these chromosomes and until these tumor suppressor genes are identified, the functional consequences of these deletions and the molecular basis of these myeloid disorders cannot be completely understood. We evaluated loss of heterozygosity (LOH) in 44 patients (18 MDS and 26 AML, diagnosed according to WHO classification criteria) at diagnosis, using a four-microsatellite marker panel: an intragenic marker on the 7th intron of gene IRF-1 of the 5q31.1 region and three markers located inside the 7q31.1 region and correlated the LOH with karyotype abnormalities. The microsatellites chosen corresponded to chromosome regions frequently deleted in MDS/AML. The samples with Q (peak area) less than or equal to 0.50 were indicative of LOH. The percent of informative samples (i.e., heterozygous) for the intragenic microsatellite in gene IRF-1 and in loci D7S486, D7S515 and D7S522 were 66.6, 73.7, 75.5, and 48.8%, respectively. Cytogenetic abnormalities by G-banding were found in 36% (16/44) of the patients (2 of 18 MDS and 14 of 26 AML patients). We found a significantly positive association of the occurrence of LOH with abnormal karyotype (P < 0.05; chi-square test) and there were cases with LOH but the karyotype was normal (by G-banding). These data indicate that LOH in different microsatellite markers is possibly an event previous to chromosomal abnormalities in these myeloid neoplasias.

Association of loss of heterozygosity with cytogenetic abnormalities in acute myeloid leukemia and myelodysplastic syndrome

Deletions on chromosomes 5 and 7 are frequently seen in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). It is assumed that these deletions indicate loss of tumor suppressor genes on these chromosomes and until these tumor suppressor genes are identified, the functional consequences of these deletions and the molecular basis of these myeloid disorders cannot be completely understood. We evaluated loss of heterozygosity (LOH) in 44 patients (18 MDS and 26 AML, diagnosed according to WHO classification criteria) at diagnosis, using a four-microsatellite marker panel: an intragenic marker on the 7th intron of gene IRF-1 of the 5q31.1 region and three markers located inside the 7q31.1 region and correlated the LOH with karyotype abnormalities. The microsatellites chosen corresponded to chromosome regions frequently deleted in MDS/AML. The samples with Q (peak area) less than or equal to 0.50 were indicative of LOH. The percent of informative samples (i.e., heterozygous) for the intragenic microsatellite in gene IRF-1 and in loci D7S486, D7S515 and D7S522 were 66.6, 73.7, 75.5, and 48.8 percent, respectively. Cytogenetic abnormalities by G-banding were found in 36 percent (16/44) of the patients (2 of 18 MDS and 14 of 26 AML patients). We found a significantly positive association of the occurrence of LOH with abnormal karyotype (P < 0.05; chi-square test) and there were cases with LOH but the karyotype was normal (by G-banding). These data indicate that LOH in different microsatellite markers is possibly an event previous to chromosomal abnormalities in these myeloid neoplasias.

Cockroaches as carriers of fungi of medical importance.

The fungal pathogenic flora of the external surface of 103 cockroaches (Periplaneta americana) collected from the intensive care unit of a hospital were investigated. In this study, a high percentage of test cockroaches (93.2%) were found to carry fungi of medical importance. The main fungi isolated were species of Candida, Aspergillus and Penicillium. Information about the carriage of pathogenic fungi by cockroaches in hospital environment is scanty. The results suggest that cockroaches can play a role in dissemination of fungi, which they can carry on their external surface.

Plasmablastic multiple myeloma is associated with increased vascular endothelial growth factor immunoexpression.

The biologic basis of the negative prognosis of plasmablastic myeloma is not fully understood. To determine whether histologically aggressive multiple myeloma (MM) is associated with a more angiogenic marrow environment, bone marrow samples from 50 recently diagnosed MM patients were evaluated. Twelve percent (6/50) of patients presented plasmablastic MM, and this feature correlated with moderate/strong intensity of vascular endothelial growth factor staining of plasma cells (P = 0.036). Although plasmablastic MM was not associated with increasing of microvessel density, this new evidence of increased expression of vascular endothelial growth factor on plasmablasts suggests that the adverse prognosis conferred by plasmablastic disease may be due, at least in part, to secretion of this angiogenic cytokine, also suggesting that the subset of MM patients with plasmablastic features may derive particular benefit from antiangiogenic therapies.

Plasmablastic multiple myeloma is associated with increased vascular endothelial growth factor immunoexpression

The biologic basis of the negative prognosis of plasmablastic myeloma is not fully understood. To determine whether histologically aggressive multiple myeloma (MM) is associated with a more angiogenic marrow environment, bone marrow samples from 50 recently diagnosed MM patients were evaluated. Twelve percent (6/50) of patients presented plasmablastic MM, and this feature correlated with moderate/strong intensity of vascular endothelial growth factor staining of plasma cells (P = 0.036). Although plasmablastic MM was not associated with increasing of microvessel density, this new evidence of increased expression of vascular endothelial growth factor on plasmablasts suggests that the adverse prognosis conferred by plasmablastic disease may be due, at least in part, to secretion of this angiogenic cytokine, also suggesting that the subset of MM patients with plasmablastic features may derive particular benefit from antiangiogenic therapies.

Antifungal activity of Ocimum gratissimum towards dermatophytes.

The development of more effective and less toxic antifungal agents is required for the treatment of dermatophytosis. Plants and their preparations have been used as medicines against infectious diseases. Extracts of Ocimum gratissimum leaves were investigated for in vitro antifungal activity, using agar dilution technique against dermatophytes. The extracts (hexane, chloroform fractions, the essential oil and eugenol) produced antifungal activities against Microsporum canis, M. gypseum, Trichophyton rubrum and T. mentagrophytes. Trichophyton rubrum, the most common aetiological agent of dermatophytosis in Goiânia, state of Goiás, Brazil, was also the most susceptible dermatophyte. The hexane fraction and eugenol were the most active. Hexane fraction inhibited the growth of 100% of dermatophytes at a concentration of 125 microg ml(-1), while eugenol inhibited the growth of 80% of dermatophytes at this same concentration. These results show that extracts of O. gratissimum are active in vitro against human pathogenic dermatophytes.

Early nuclear alterations and immunohistochemical expression of Ki-67, Erb-B2, vascular endothelial growth factor (VEGF), transforming growth factor (TGF-beta1) and integrine-linked kinase (ILK) two days after tamoxifen in breast carcinoma.

The purpose of the present study was to evaluate breast carcinoma samples before and two days after treatment with tamoxifen in order to analyse early histopathological alterations--particularlynuclear alterations-- as well as immunohistochemical expression of Ki-67, Erb-B2, VEGF, TGF-beta1 and ILK proteins. Twenty one cases of invasive ductal and lobular breast carcinoma were studied. Patients were submitted to biopsy of the lesion and, after confirmation of the diagnosis, they received 20 mg of tamoxifen a day, beginning two days before surgery. The samples obtained during biopsy and after surgery were stained with HE for histopathological diagnosis. Estrogen receptor was positive in 18 cases and negative in 3. The immunohistochemical method was applied for the detection of Ki-67, Erb-B2, protein, vascular endothelial growth factor (VEGF), transforming growth factor beta (TGF-beta1) and integrin linked kinase (ILK). Two days after tamoxifen treatment, the following results were observed: 1) decrease in the cell volume, chomatine condensation, nucleoli less evident and clearly defined nuclear limits; 2) significant reduction in the expression of Erb-B2 protein and significant increase in the expression of TGF-beta1 protein; 3) expression of others proteins (Ki-67, VEGF and ILK) was not altered during the indicated time frame. Our results suggest that analyzing nuclear alterations and expression of Erb-B2 and TGF-beta1 proteins would be useful to assess the initial response to tamoxifen.

Fungal infections in marrow transplant recipients under antifungal prophylaxis with fluconazole.

Fungal infection is one of the most important causes of morbidity and mortality in bone marrow transplant (BMT) recipients. The growing incidence of these infections is related to several factors including prolonged granulocytopenia, use of broad-spectrum antibiotics, conditioning regimens, and use of immunosuppression to avoid graft-versus-host disease (GvHD). In the present series, we report five cases of invasive mold infections documented among 64 BMT recipients undergoing fluconazole antifungal prophylaxis: 1) A strain of Scedosporium prolificans was isolated from a skin lesion that developed on day +72 after BMT in a chronic myeloid leukemic patient. 2) Invasive pulmonary aspergillosis (Aspergillus fumigatus) was diagnosed on day +29 in a patient with a long period of hospitalization before being transplanted for severe aplastic anemia. 3) A tumoral lung lesion due to Rhizopus arrhizus (zygomycosis) was observed in a transplanted patient who presented severe chronic GvHD. 4) A tumoral lesion due to Aspergillus spp involving the 7th, 8th and 9th right ribs and local soft tissue was diagnosed in a BMT patient on day +110. 5) A patient with a history of Ph1-positive acute lymphocytic leukemia exhibited a cerebral lesion on day +477 after receiving a BMT during an episode of severe chronic GvHD. At that time, blood and spinal fluid cultures yielded Fusarium sp. Opportunistic infections due to fungi other than Candida spp are becoming a major problem among BMT patients receiving systemic antifungal prophylaxis with fluconazole.

Fungal infections in marrow transplant recipients under antifungal prophylaxis with fluconazole

Fungal infection is one of the most important causes of morbidity and mortality in bone marrow transplant (BMT) recipients. The growing incidence of these infections is related to several factors including prolonged granulocytopenia, use of broad-spectrum antibiotics, conditioning regimens, and use of immunosuppression to avoid graft-versus-host disease (GvHD). In the present series, we report five cases of invasive mold infections documented among 64 BMT recipients undergoing fluconazole antifungal prophylaxis: 1) A strain of Scedosporium prolificans was isolated from a skin lesion that developed on day +72 after BMT in a chronic myeloid leukemic patient. 2) Invasive pulmonary aspergillosis (Aspergillus fumigatus) was diagnosed on day +29 in a patient with a long period of hospitalization before being transplanted for severe aplastic anemia. 3) A tumoral lung lesion due to Rhizopus arrhizus (zygomycosis) was observed in a transplanted patient who presented severe chronic GvHD. 4) A tumoral lesion due to Aspergillus spp involving the 7th, 8th and 9th right ribs and local soft tissue was diagnosed in a BMT patient on day +110. 5) A patient with a history of Ph1-positive acute lymphocytic leukemia exhibited a cerebral lesion on day +477 after receiving a BMT during an episode of severe chronic GvHD. At that time, blood and spinal fluid cultures yielded Fusarium sp. Opportunistic infections due to fungi other than Candida spp are becoming a major problem among BMT patients receiving systemic antifungal prophylaxis with fluconazole

Açäo dos raios X corpo total sobre os neutrófilos do sangue periférico em primata Cebus apella (macaco prego) / Effects of whole-body X-radiation on the neutrophils of the peripheral blood of the primate Cebus apella (weeping capuchin)

Amostras de sangue periférico foram obtidas de cinco primatas Cebus apella (macaco prego), antes e após exposiçäo aos raios X corpo inteiro, na dose única de 25,8 mC/kg (100R). Parte das amostras foi utilizada para a contagem global de cariosquizes e o restante para a realizaçäo de extensöes sanguíneas e submetidas à coloraçäo de Wright e aos seguintes métodos citoquímicos: ácido periódico Schiff (PAS) para a identificaçäo de glicogênio, Sudan black B para a detecçäo de fosfolipídios e o-toluidina-água oxigenada para a demonstraçäo da mieloperoxidase. Com o método de Wright foram observadas aos 1, 3 e 6 dias após exposiçäo à radiaçäo, alteraçöes nucleares e citoplasmáticas. Após aplicaçäo dos métodos citoquímicos acima referidos, foram observados, de modo geral, nos mesmos períodos de tempo após irradiaçäo: alteraçäo no padräo de distribuiçäo dos grânulos de glicogênio, grânulos mieloperoxidase positivos e sudanófilos de neutrófilos. No que diz respeito a cariosquizes, constatou-se um aumento dos mesmos após 1 dia, persistindo até o 3§ dia após irradiaçäo. Noventa dias após, näo foi observada nenhuma alteraçäo acima referida

Evaluation of the effect of ionizing radiation of mouse hemocytopoietic tissue by reticulocyte count

The effects of exposure to a single, whole body X-ray dose of 154.8 mC/Kg (600 R) on mouse (Mus musculus) hemocytopoietic tissue were analyzed by means of reticulocyte counts in peripheral blood, evaluating indirectly variations of the erythrocyte sector of bone marrow. The efficiency of the method for the evaluation of this tissue was demonstrated, constituting one more radiobiologic parameter to corroborate those existing already