Kneipp L.F.,Laboratorio Of Taxonomia |
Alviano C.S.,Institute Microbiologia Prof Paulo Of Goes |
Meyer-Fernandes J.R.,Federal University of Rio de Janeiro |
De Araujo Soares R.M.,Institute Microbiologia Prof Paulo Of Goes
Oral Diseases | Year: 2010
Objective: This study describes the expression of acidic ectophosphatase activity on twenty isolates of C. albicans from oral cavities of HIV-infected children (HIV+) and compares them with fifteen isolates from HIV-negative children (HIV-), as well as the fungal adhesion to epithelial cells and medical records. Methods: The activities were measured in intact cells grown in BHI medium for 48 h at 37°C. Phosphatase activity was assayed at pH 5.5 using 4-methylumbelliferyl phosphate. Yeast adhesion was measured using the MA 104 epithelial cell line. Results: Mean values of ectophosphatase activity were 610.27 ± 166.36 and 241.25 ± 78.96 picomoles 4- methylumbelliferone/h/107 cells for HIV+ and HIV- group, respectively (P = 0.049). No correlation between C. albicans enzyme activity from HIV children with viral load and CD4 percentual was observed. Yeasts with high enzyme activity, isolated from HIV+ children showed greater adherence than yeasts with basal levels of ectophosphatases from HIV- (Spearman correlation, r = 0.8). Surface phosphatase activity was apparently involved in the adhesion to host cells, as the enhanced attachment of C. albicans to host epithelial cells was reversed by pretreatment of yeast with sodium orthovanadate (1 mM), an acid phosphatase inhibitor. Conclusion: These results show that C. albicans from HIV+ has an ectophosphatase activity significantly higher than the other isolates. Yeasts expressing higher levels of surface phosphatase activity showed greater adhesion to epithelial cells. So, the activity of acidic surface phosphatases on these cells may contribute to the early mechanisms required for disease establishment. © 2010 John Wiley & Sons A/S.
Azevedo Z.M.,Paediatric Intensive Care Unit |
Moore D.B.,Paediatric Intensive Care Unit and Laboratory of Human Pathophysiology |
Lima F.C.,Paediatric Intensive Care Unit |
Cardoso C.C.,Oswaldo Cruz Institute |
And 7 more authors.
Human Immunology | Year: 2012
Accumulating evidence indicates that genetic background influences the outcome of sepsis, which despite medical advances continues to be a major cause of morbidity and mortality. This study aimed to evaluate the influence of SNPs LTA +252A > G, TNF-863C > A and TNF-308G > A on susceptibility to sepsis, acute respiratory distress syndrome (ARDS), septic shock and sepsis mortality. A prospective case-control study was carried out in a Brazilian pediatric intensive care unit and included 490 septic pediatric patients submitted to mechanical ventilation and 610 healthy children. No SNP association was found with respect to sepsis susceptibility. Nevertheless, a haplotype was identified that was protective against sepsis (+252. A/-863. A/-308. G; OR = 0.65; p= 0.03). We further observed protection against ARDS in TNF-308 GA genotype carriers (OR = 0.29; p= 0.0006) and -308. A allele carriers (OR = 0.40; p= 0.003). In addition, increased risk for ARDS was detectable with the TNF-863 CA genotype (OR = 1.83; p= 0.01) and the -863A carrier status (OR = 1.82; p= 0.01). After stratification according to age, this outcome remained significantly associated with the -308GA genotype in infants. Finally, protection against sepsis-associated mortality was found for the TNF-308 GA genotype (OR = 0.22; p= 0.04). Overall, our findings document a protective effect of the TNF-308 GA genotype for the ARDS and sepsis mortality outcomes, further providing evidence for an increased risk of ARDS associated with the TNF-863 CA genotype. Trial registration (www.clinicaltrials.gov): NCT00792883. © 2012 American Society for Histocompatibility and Immunogenetics.
Cotta S.R.,Federal University of Rio de Janeiro |
da Mota F.F.,Federal University of Rio de Janeiro |
Tupinamba G.,Institute Microbiologia Prof Paulo Of Goes |
Ishida K.,Institute Biofisica Carlos Chagas Filho |
And 7 more authors.
World Journal of Microbiology and Biotechnology | Year: 2012
In a search for an antifungal substance with activity against the dermatophyte fungus Trichophyton rubrum, strain POC 115 was chosen among different Paenibacillus strains for its phenotypic and genetic characterization and for preliminary characterization of its antimicrobial substance. Strain POC 115 was identified as belonging to Paenibacillus kribbensis. Physico-chemical characterization of the antimicrobial substance showed that it was not stable during heat and organic solvents treatments, but its activity was preserved at a wide range of pH and after treatment with pronase E, trypsin and DNase I. The crude concentrated supernatant of POC 115 culture was partially purified and the fraction presenting antimicrobial activity was further analyzed by UPLC/Mass Spectrometry. Two peaks were observed at 2. 02 (mass 1,207 D) and 2. 71 (mass 1,014 D) min in the mass chromatogram. The antimicrobial substance produced by POC 115 was correlated to iturin family compounds based on a set of primers designed for the amplification of PKS operon in the POC 115 genome. As happens with the mode of action of the antibiotics of the iturin group, the AMS produced by POC 115 caused the disruption of cytoplasmic membrane of T. rubrum and the subsequent withdraw of the intracellular material. This is the first report on the production of antimicrobial substances in P. kribbensis, and it may be of great relevance as an alternative or supplementary substance to antifungal drugs currently used against dermatophytes. © 2011 Springer Science+Business Media B.V.
Korenblum E.,Federal University of Rio de Janeiro |
De Araujo L.V.,Federal University of Rio de Janeiro |
Guimaraes C.R.,Federal University of Rio de Janeiro |
De Souza L.M.,Federal University of Paraná |
And 8 more authors.
BMC Microbiology | Year: 2012
Background: Bacillus sp. H2O-1, isolated from the connate water of a Brazilian reservoir, produces an antimicrobial substance (denoted as AMS H2O-1) that is active against sulfate reducing bacteria, which are the major bacterial group responsible for biogenic souring and biocorrosion in petroleum reservoirs. Thus, the use of AMS H2O-1 for sulfate reducing bacteria control in the petroleum industry is a promising alternative to chemical biocides. However, prior to the large-scale production of AMS H2O-1 for industrial applications, its chemical structure must be elucidated. This study also analyzed the changes in the wetting properties of different surfaces conditioned with AMS H2O-1 and demonstrated the effect of AMS H2O-1 on sulfate reducing bacteria cells. Results: A lipopeptide mixture from AMS H2O-1 was partially purified on a silica gel column and identified via mass spectrometry (ESI-MS). It comprises four major components that range in size from 1007 to 1049 Da. The lipid moiety contains linear and branched β-hydroxy fatty acids that range in length from C13 to C16. The peptide moiety contains seven amino acids identified as Glu-Leu-Leu-Val-Asp-Leu-Leu.Transmission electron microscopy revealed cell membrane alteration of sulfate reducing bacteria after AMS H2O-1 treatment at the minimum inhibitory concentration (5 μg/ml). Cytoplasmic electron dense inclusions were observed in treated cells but not in untreated cells. AMS H2O-1 enhanced the osmosis of sulfate reducing bacteria cells and caused the leakage of the intracellular contents. In addition, contact angle measurements indicated that different surfaces conditioned by AMS H2O-1 were less hydrophobic and more electron-donor than untreated surfaces. Conclusion: AMS H2O-1 is a mixture of four surfactin-like homologues, and its biocidal activity and surfactant properties suggest that this compound may be a good candidate for sulfate reducing bacteria control. Thus, it is a potential alternative to the chemical biocides or surface coating agents currently used to prevent SRB growth in petroleum industries. © 2012 Korenblum et al.; licensee BioMed Central Ltd.
Rocha J.D.B.,Institute Microbiologia Prof Paulo Of Goes |
Decote-Ricardo D.,Institute Microbiologia Prof Paulo Of Goes |
Redner P.,Federal University of Rio de Janeiro |
Lopes U.G.,Federal University of Rio de Janeiro |
And 4 more authors.
Planta Medica | Year: 2010
The aqueous fraction of the ethanolic extract of the plant Cissampelos sympodialis (Menispermaceae) was previously described to inhibit B cell function. The alkaloid warifteine is the major component of this extract. In the present study we investigated the effect of warifteine on B lymphocyte function and characterized its mechanism of action. Purified splenic murine B lymphocytes were stimulated with either Toll-like receptor (TLR) ligands (LPS, Pamys and CpG oligodeoxynucleotides) or anti-IgM antibody and the effect of warifteine on B cell response was investigated. Warifteine inhibited both the proliferative response and immunoglobulin (Ig) secretion induced by these stimuli. Kinetics studies demonstrated that warifteine blocked B cell function even when added after 24h of a 72h culture. The inhibitory effect of warifteine was also detected in cultures activated by phorbol myristate acetate and calcium ionophore. We investigated the signal transduction pathways blocked by warifteine. It did not modify the total protein phosphorylation pattern in LPS and anti-IgM-stimulated B cell cultures. It did, however, decrease the rise in intracellular calcium levels, the phosphorylation of the mitogen activated protein kinase (MAPK) ERK and the intranuclear levels of the transcription factor NFB. Warifteine also induced an increase in cAMP and its effect on LPS-induced proliferation was mimicked by the control adenyl cyclase activator forskolin. In vivo Ig production induced by the TI-2 antigen TNP-ficoll was also inhibited by warifteine. Taking together, our data suggest that warifteine is a potent inhibitor of B cell response both in vitro and in vivo and that this effect may be due to the induction of increased intracellular cAMP levels, suggesting that this substance may be useful as a modulator of B cell function. © Georg Thieme Verlag KG Stuttgart - New York.
Balassiano I.T.,Institute Microbiologia Prof Paulo Of Goes |
Balassiano I.T.,Instituto Oswaldo Cruz |
Santos-Filho J.D.,Institute Microbiologia Prof Paulo Of Goes |
Vital-Brazil J.M.,Instituto Oswaldo Cruz |
And 6 more authors.
Antonie van Leeuwenhoek, International Journal of General and Molecular Microbiology | Year: 2011
Clostridium difficile is an important nosocomial enteric pathogen and is the etiological agent of pseudomembranous colites. Recently, the rates of C. difficile infection (CDI) have increased worldwide, but in Brazil few data about this situation and the incidence of clonal types of C. difficile exist. This study aimed to isolate and characterize C. difficile strains from samples obtained of a university hospital (HUCFF) in Rio de Janeiro city, Brazil. CDI was identified by ELISA in 27.1% of HUCFF-in-patients enrolled in the study, and the bacterium was recovered from eight of these fecal samples. All strains, except one, presented tcdA and tcdB genes and presented neither the cdtA and cdtB genes nor any significant deletions in the tcdC gene. All strains were sensitive to metronidazole, vancomycin and moxifloxacin, and resistant to clindamycin, ciprofloxacin and levofloxacin. PCR-ribotyping and PFGE revealed four different clonal types among the isolates. The Brazilian PCR-ribotype 133 accounted for 50% of strains isolated, and PCR-ribotype 233 strains were obtained from 25% of the in-patients. The prevalence and resurgence of the Brazilian PCR-ribotype 133 among the hospitalized patients of HUCFF was established, and cross-infection of different patients associated to the same PCR-ribotypes was detected. Our results emphasize the importance of the diagnosis and control of CDI in order to prevent the emergence of specific clones that can lead to C. difficile-associated outbreaks in Brazilian hospitals. © 2010 Springer Science+Business Media B.V.
Oliveira D.L.,Institute Microbiologia Prof Paulo Of Goes |
Freire-de-Lima C.G.,Federal University of Rio de Janeiro |
Nosanchuk J.D.,Yeshiva University |
Casadevall A.,Yeshiva University |
And 2 more authors.
Infection and Immunity | Year: 2010
Cryptococcus neoformans and distantly related fungal species release extracellular vesicles that traverse the cell wall and contain a varied assortment of components, some of which have been associated with virulence. Previous studies have suggested that these extracellular vesicles are produced in vitro and during animal infection, but the role of vesicular secretion during the interaction of fungi with host cells remains unknown. In this report, we demonstrate by fluorescence microscopy that mammalian macrophages can incorporate extracellular vesicles produced by C. neoformans. Incubation of cryptococcal vesicles with murine macrophages resulted in increased levels of extracellular tumor necrosis factor alpha (TNF-α), interleukin-10 (IL-10), and transforming growth factor β (TGF-β). Vesicle preparations also resulted in a dose-dependent stimulation of nitric oxide production by phagocytes, suggesting that vesicle components stimulate macrophages to produce antimicrobial compounds. Treated macrophages were more effective at killing C. neoformans yeast. Our results indicate that the extracellular vesicles of C. neoformans can stimulate macrophage function, apparently activating these phagocytic cells to enhance their antimicrobial activity. These results establish that cryptococcal vesicles are biologically active. Copyright © 2010, American Society for Microbiology. All Rights Reserved.
Alviano D.S.,Federal University of Rio de Janeiro |
Barreto A.L.S.,Federal University of Rio de Janeiro |
Dias F.A.,Federal University of Rio de Janeiro |
Rodrigues I.A.,Institute Microbiologia Prof Paulo Of Goes |
And 4 more authors.
Frontiers in Microbiology | Year: 2012
Leishmaniasis and trypanosomiasis are two neglected and potentially lethal diseases that affect mostly the poor and marginal populations of developing countries around the world and consequently have an important impact on public health. Clinical manifestations such as cutaneous, mucocutaneous, and visceral disorders are the most frequent forms of leishmaniasis, a group of diseases caused by several Leishmania spp. American trypanosomiasis, or Chagas disease, is caused by Trypanosoma cruzi, a parasite that causes progressive damage to different organs, particularly the heart, esophagus, and lower intestine. African trypanosomiasis, or sleeping sickness, is caused by Trypanosoma brucei and is characterized by first presenting as an acute form that affects blood clotting and then becoming a chronic meningoencephalitis. The limited number, low efficacy, and side effects of conventional anti-leishmania and anti-trypanosomal drugs and the resistance developed by parasites are the major factors responsible for the growth in mortality rates. Recent research focused on plants has shown an ingenious way to obtain a solid and potentially rich source of drug candidates against various infectious diseases. Bioactive phytocompounds present in the crude extracts and essential oils of medicinal plants are components of an important strategy linked to the discovery of new medicines. These compounds have proven to be a good source of therapeutic agents for the treatment of leishmaniasis and trypanosomiasis. This work highlights some chemotherapeutic agents while emphasizing the importance of plants as a source of new and powerful drugs against these widespread diseases. © 2012 Alviano,Barreto,Dias, Rodrigues, Rosa, Alviano and Soares.
Korenblum E.,Institute Microbiologia Prof Paulo Of Goes |
Souza D.B.,Institute Microbiologia Prof Paulo Of Goes |
Penna M.,Petrobras |
Seldin L.,Institute Microbiologia Prof Paulo Of Goes
International Journal of Microbiology | Year: 2012
Crude oil samples with high- and low-water content from two offshore platforms (PA and PB) in Campos Basin, Brazil, were assessed for bacterial communities by 16S rRNA gene-based clone libraries. RDP Classifier was used to analyze a total of 156 clones within four libraries obtained from two platforms. The clone sequences were mainly affiliated with Gammaproteobacteria (78.2 of the total clones); however, clones associated with Betaproteobacteria (10.9), Alphaproteobacteria (9), and Firmicutes (1.9) were also identified. Pseudomonadaceae was the most common family affiliated with these clone sequences. The sequences were further analyzed by MOTHUR, yielding 81 operational taxonomic units (OTUs) grouped at 97 stringency. Richness estimators also calculated by MOTHUR indicated that oil samples with high-water content were the most diverse. Comparison of bacterial communities present in these four samples using LIBSHUFF and Principal Component Analysis (PCA) indicated that the water content significantly influenced the community structure only of crude oil obtained from PA. Differences between PA and PB libraries were observed, suggesting the importance of the oil field as a driver of community composition in this habitat. Copyright © 2012 Elisa Korenblum et al.
Grigorevski-Lima A.L.,Institute Microbiologia Prof Paulo Of Goes |
De Oliveira M.M.Q.,Institute Microbiologia Prof Paulo Of Goes |
Do Nascimento R.P.,Federal University of Rio de Janeiro |
Da Silva Bon E.P.,University of Sao Paulo |
Coelho R.R.R.,Institute Microbiologia Prof Paulo Of Goes
Applied Biochemistry and Biotechnology | Year: 2013
Trichoderma atroviride 676 was studied to evaluate its efficiency in the production of some lignocellulolytic enzymes, using lignocellulosic residual biomass. Best results were obtained when 3.0 % (w/v) untreated sugarcane bagasse was used (61.3 U mL-1 for xylanase, 1.9 U mL-1 for endoglucanase, 0.25 U mL-1 for FPase, and 0.17 U mL-1 for β- glucosidase) after 3-4 days fermentation. The maximal enzymatic activity for endoglucanase, FPase, and xylanase were observed at 50-60 °C and pH4.0-5.0, whereas thermal stability at 50 °C (CMCase and FPase) or 40 °C (xylanase) was obtained after 8 h. Zymograms have shown two bands of 104 and 200 kDa for endoglucanases and three bands for xylanase (23, 36, and 55.7 kDa). The results obtained with T. atroviride strain 676 were comparable to those obtained with the cellulolytic strain Trichoderma reesei RUT-C30, indicating, in the studied conditions, its great potential for biotechnological application, especially lignocellulose biomass hydrolysis. © Springer Science+Business Media New York 2013.