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1.
Appl Environ Microbiol ; 81(5): 1847-58, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25548058

RESUMO

Identification of proteins that were present in a polyhydroxybutyrate (PHB) granule fraction isolated from Ralstonia eutropha but absent in the soluble, membrane, and membrane-associated fractions revealed the presence of only 12 polypeptides with PHB-specific locations plus 4 previously known PHB-associated proteins with multiple locations. None of the previously postulated PHB depolymerase isoenzymes (PhaZa2 to PhaZa5, PhaZd1, and PhaZd2) and none of the two known 3-hydroxybutyrate oligomer hydrolases (PhaZb and PhaZc) were significantly present in isolated PHB granules. Four polypeptides were found that had not yet been identified in PHB granules. Three of the novel proteins are putative α/ß-hydrolases, and two of those (A0671 and B1632) have a PHB synthase/depolymerase signature. The third novel protein (A0225) is a patatin-like phospholipase, a type of enzyme that has not been described for PHB granules of any PHB-accumulating species. No function has been ascribed to the fourth protein (A2001), but its encoding gene forms an operon with phaB2 (acetoacetyl-coenzyme A [CoA] reductase) and phaC2 (PHB synthase), and this is in line with a putative function in PHB metabolism. The localization of the four new proteins at the PHB granule surface was confirmed in vivo by fluorescence microscopy of constructed fusion proteins with enhanced yellow fluorescent protein (eYFP). Deletion of A0671 and B1632 had a minor but detectable effect on the PHB mobilization ability in the stationary growth phase of nutrient broth (NB)-gluconate cells, confirming the functional involvement of both proteins in PHB metabolism.


Assuntos
Proteínas de Bactérias/análise , Proteínas de Bactérias/isolamento & purificação , Cupriavidus necator/química , Grânulos Citoplasmáticos/química , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Proteoma/análise , Proteínas de Bactérias/genética , Cupriavidus necator/genética , Cupriavidus necator/metabolismo , Deleção de Genes , Hidrolases/análise , Hidrolases/genética , Hidrolases/isolamento & purificação , Microscopia de Fluorescência , Óperon , Fosfolipases/análise , Fosfolipases/genética , Fosfolipases/isolamento & purificação
2.
J Prosthet Dent ; 112(6): 1349-55, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25258264

RESUMO

STATEMENT OF PROBLEM: Candida biofilms on denture surfaces are substantially reduced after a single immersion in denture cleanser. However, whether this effect is maintained when dentures are immersed in cleanser daily is unclear. PURPOSE: The purpose of this study was to evaluate the effect of the daily use of enzymatic cleanser on Candida albicans biofilms on denture base materials. MATERIAL AND METHODS: The surfaces of polyamide and poly(methyl methacrylate) resin specimens (n=54) were standardized and divided into 12 groups (n=9 per group), according to study factors (material type, treatment type, and periods of treatment). Candida albicans biofilms were allowed to form over 72 hours, after which the specimens were treated with enzymatic cleanser once daily for 1, 4, or 7 days. Thereafter, residual biofilm was ultrasonically removed and analyzed for viable cells (colony forming units/mm(2)) and enzymatic activity (phospholipase, aspartyl-protease, and hemolysin). Factors that interfered with the response variables were analyzed by 3-way ANOVA with the Holm-Sidak multiple comparison method (α=.05). RESULTS: Polyamide resin presented more viable cells of Candida albicans (P<.001) for both the evaluated treatment types and periods. Although enzymatic cleansing significantly (P<.001) reduced viable cells, daily use did not maintain this reduction (P<.001). Phospholipase activity significantly increased with time (P<.001) for both materials and treatments. However, poly(methyl methacrylate) based resin (P<.001) and enzymatic cleansing treatment (P<.001) contributed to lower phospholipase activity. Aspartyl-protease and hemolysin activities were not influenced by study factors (P>.05). CONCLUSIONS: Although daily use of an enzymatic cleanser reduced the number of viable cells and phospholipase activity, this treatment was not effective against residual biofilm over time.


Assuntos
Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Materiais Dentários/química , Higienizadores de Dentadura/uso terapêutico , Nylons/química , Polimetil Metacrilato/química , Ácido Aspártico Proteases/análise , Boratos/uso terapêutico , Candida albicans/enzimologia , Contagem de Colônia Microbiana , Película Dentária/microbiologia , Proteínas Hemolisinas/análise , Humanos , Imersão , Teste de Materiais , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Fosfolipases/análise , Método Simples-Cego , Sulfatos/uso terapêutico , Propriedades de Superfície , Fatores de Tempo
3.
Nano Lett ; 11(4): 1401-5, 2011 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-20795711

RESUMO

A flexible nanoparticle-based phospholipase (PL) assay is demonstrated in which the enzymatic substrate is decoupled from the nanoparticle surface. Liposomes are loaded with a polypeptide that is designed to heteroassociate with a second polypeptide immobilized on gold nanoparticles. Release of this polypeptide from the liposomes, triggered by PL, induces a folding-dependent nanoparticle bridging aggregation. The colorimetric response from this aggregation enables straightforward and continuous detection of PL in the picomolar range. The speed, specificity, and flexibility of this assay make it appropriate for a range of applications, from point of care diagnostics to high-throughput pharmaceutical screening.


Assuntos
Colorimetria/métodos , Lipossomos/química , Nanoestruturas/química , Fosfolipases/análise , Fosfolipases/química , Ativação Enzimática , Nanoestruturas/ultraestrutura , Tamanho da Partícula
4.
Lett Appl Microbiol ; 46(4): 445-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18346138

RESUMO

AIMS: To assess of the genotypic diversity of Candida albicans isolated from removable prosthesis wearers, with and without denture-related stomatitis (DRS). The occurrence of different genotypes in pathological and control cases was investigated. METHODS AND RESULTS: One hundred and sixty-four isolates of C. albicans obtained from different oral cavity locations were compared by randomly amplified polymorphic DNA (RAPD). The coherence of this analysis was confirmed by genotyping a selected group of isolates with pulsed field gel electrophoresis (PFGE). Among the 164 isolates, 150 were grouped into seven groups on the basis of their RAPD patterns. Three of these groups (comprising 54 isolates) had significant (alpha < 0.10) predominance of clinical or control cases. For the other isolates, no significant differences were observed between control and DRS cases. Occasionally, more than one genotype was found in the same person. These findings were sustained by PFGE analysis. No relevant associations between the genotypic patterns and pathology level were found. CONCLUSIONS: This study evidenced that C. albicans with similar genotypes may be found in individuals with DRS and in control cases. SIGNIFICANCE AND IMPACT OF THE STUDY: This conclusion hints the involvement of other aetiological factors that alone or in association with C. albicans may trigger the emergence of DRS.


Assuntos
Candida albicans/classificação , Candida albicans/genética , Dentaduras/efeitos adversos , Boca/microbiologia , Estomatite sob Prótese/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Candida albicans/enzimologia , Candida albicans/isolamento & purificação , Análise por Conglomerados , Impressões Digitais de DNA , DNA Fúngico/genética , Eletroforese em Gel de Campo Pulsado , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Hidrolases/análise , Fosfolipases/análise , Técnica de Amplificação ao Acaso de DNA Polimórfico
5.
Arch Oral Biol ; 52(7): 691-6, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17241611

RESUMO

BACKGROUND AND OBJECTIVES: The extracellular phospholipases of Candida albicans are considered to play a significant role in the pathogenesis of human infections. Therefore 23 clinical oral isolates of C. albicans from patients with denture stomatitis and 22 commensal oral isolates obtained from the palatal mucosa of healthy subjects were assayed for phospholipase activity. It is generally accepted that chlorhexidine gluconate is an appropriate adjunct or an alternative to antimycotic therapy in the management of oral candidiasis. However, the intraoral concentrations of this antiseptic fluctuate considerably due to the dynamics of the oral cavity. So the second main objective of this study was to investigate the effect of brief exposure (30 min) to two sub-therapeutic concentrations (0.002% and 0.0012%) of chlorhexidine gluconate on the value of phospholipase production (Pz) of C. albicans. METHOD: An in vitro phospholipase production was done by plate assay method using an egg yolk-agar medium. RESULTS: No significant differences were found in the number of C. albicans isolates producing phospholipase between two groups. However, the mean value of Pz produced by the isolates from patients with denture stomatitis was significantly (p<0.05) higher than the commensals. Exposure of the isolates to 0.002% and 0.0012% chlorhexidine led to a significant (p<0.001 and p<0.01, respectively) reduction in the amount of phospholipase. CONCLUSION: The results of this study imply that sub-therapeutic levels of chlorhexidine may modulate candidal phospholipase activity, thereby suppressing pathogenicity of C. albicans.


Assuntos
Candida albicans/enzimologia , Candidíase Bucal/microbiologia , Fosfolipases/análise , Estomatite sob Prótese/microbiologia , Anti-Infecciosos Locais/administração & dosagem , Anti-Infecciosos Locais/uso terapêutico , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Candida albicans/efeitos dos fármacos , Clorexidina/administração & dosagem , Clorexidina/análogos & derivados , Clorexidina/uso terapêutico , Humanos , Palato/microbiologia , Fosfolipases/efeitos dos fármacos
6.
J Appl Oral Sci ; 25(3): 274-281, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28678946

RESUMO

OBJECTIVE: The aim of this study was to investigate the prevalence of isolated Candida albicans from periodontal endodontic lesions in diabetic and normoglycemic patients, and the fungi's virulence in different atmospheric conditions. MATERIAL AND METHODS: A case-control study was conducted on 15 patients with type 2 diabetes mellitus (G1) and 15 non-diabetics (G2) with periodontal endodontic lesions. Samples of root canals and periodontal pockets were plated on CHROMagar for later identification by polymerase chain reaction (PCR) and virulence test. RESULTS: C. albicans was identified in 79.2% and 20.8% of the 60 samples collected from diabetic and normoglycemic patients, respectively. Of the 30 samples collected from periodontal pockets, 13 showed a positive culture for C. albicans, with 77% belonging to G1 and 23% to G2. Of the 11 positive samples from root canals, 82% were from G1 and 18% from G2. Production of proteinase presented a precipitation zone Pz<0.63 of 100% in G1 and 72% in G2, in redox and negative (Pz=1), under anaerobic conditions in both groups. Hydrophobicity of the strains from G1 indicated 16.4% with low, 19.3% with moderate, and 64.3% with high hydrophobicity in redox. In G2, 42.2% had low, 39.8% had moderate, 18% had high hydrophobicity in redox. In anaerobic conditions, G1 showed 15.2% with low, 12.8% with moderate, and 72% with high hydrophobicity; in G2, 33.6% had low, 28.8% had moderate, and 37.6% had high hydrophobicity. There was statistical difference in the number of positive cultures between G1 and G2 (p<0.05) with predominance in G1. There was statistical difference for all virulence factors, except hemolysis (p=0.001). CONCLUSIONS: Candida albicans was isolated more frequently and had higher virulence in diabetic patients.


Assuntos
Candida albicans/isolamento & purificação , Candida albicans/patogenicidade , Doenças da Polpa Dentária/microbiologia , Diabetes Mellitus Tipo 2/microbiologia , Doenças Periodontais/microbiologia , Adulto , Idoso , Estudos de Casos e Controles , DNA Fúngico , Cavidade Pulpar/microbiologia , Doenças da Polpa Dentária/diagnóstico por imagem , Doenças da Polpa Dentária/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Eletroforese , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Pessoa de Meia-Idade , Oxirredução , Peptídeo Hidrolases/análise , Doenças Periodontais/diagnóstico por imagem , Doenças Periodontais/fisiopatologia , Bolsa Periodontal/microbiologia , Fosfolipases/análise , Reação em Cadeia da Polimerase , Radiografia Dentária , Estatísticas não Paramétricas , Virulência
7.
J Investig Clin Dent ; 6(4): 273-81, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25045148

RESUMO

AIM: The objective of the present study was to determine if blood plasma proteins could change the proteome of the acquired denture pellicle by label-free quantitative proteomics. As pellicle proteome modulates the interaction between substrates and Candida cells, we investigated its effect on the surface free energy (SFE) of the coated resin and on Candida albicans phospholipase and aspartyl proteinase activities. METHODS: Poly(methylmethacrylate) discs were exposed to saliva (control) or saliva enriched with blood plasma (experimental group). The pellicle proteome was analyzed by mass spectrometry coupled with liquid chromatography. SFE was determined by acid-base technique. After biofilm formation, phospholipase and proteinase activities were determined accordingly to classic plate methods. Data were analyzed by two-way anova and Tukey test (P < 0.05). RESULTS: α-Amylase, cystatins, mucins, and host-immune system proteins were the main proteins identified in the control group. Fibrinogen and albumin were observed only in the experimental group. Coated discs of the experimental group presented an increased SFE (P < 0.05). For both enzymes tested, the experimental group showed higher proteolytic activity (P < 0.001). CONCLUSION: Blood plasma changes the proteome of the acquired denture pellicle, increasing surface free energy and the activity of Candida albicans phospholipase and aspartyl proteinase.


Assuntos
Ácido Aspártico Proteases/análise , Proteínas Sanguíneas/fisiologia , Candida albicans/enzimologia , Película Dentária/fisiologia , Bases de Dentadura , Fosfolipases/análise , Polimetil Metacrilato/química , Adulto , Biofilmes , Proteínas Sanguíneas/análise , Cromatografia Líquida/métodos , Cistatinas/análise , Película Dentária/química , Feminino , Fibrinogênio/análise , Humanos , Imunoproteínas/análise , Técnicas In Vitro , Masculino , Mucinas/análise , Proteoma/metabolismo , Distribuição Aleatória , Albumina Sérica/análise , Tensão Superficial , Espectrometria de Massas em Tandem/métodos , alfa-Amilases/análise
8.
Biosens Bioelectron ; 18(2-3): 185-91, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12485764

RESUMO

A choline (CHO) biosensor based on the determination of H(2)O(2) generated at the electrode surface by the enzyme choline oxidase (CHOx) was developed. The biosensor consisted of CHOx retained onto a horseradish peroxidase (HRP) immobilized solid carbon paste electrode (sCPE). The HRPsCPE contained the molecule phenothiazine as redox mediator and CHOx was physically retained on the electrode surface using a dialysis membrane. Several parameters have been studied such as, mediator amount, influence of applied potential, etc. The CHO measurements were performed in 0.1 M phosphate buffer, pH 7.4. Amperometric detection of CHO was realized at an applied potential of 0.0 mV vs Ag/AgCl. The response is linear over the concentration range 5.0x10(-7)-7.0x10(-5) M, with a detection limit of 1.0x10(-7) M. This biosensor was used to detect choline released from phosphatidylcholine (PC) by phospholipase D (PLD) in isolated rat salivary gland cells stimulated by a purinergic agonist (ATP).


Assuntos
Técnicas Biossensoriais/instrumentação , Colina/análise , Colina/farmacocinética , Eletroquímica/instrumentação , Glândula Submandibular/metabolismo , Trifosfato de Adenosina/farmacologia , Oxirredutases do Álcool/química , Animais , Técnicas Biossensoriais/métodos , Colina/química , Materiais Revestidos Biocompatíveis/síntese química , Eletroquímica/métodos , Membranas Artificiais , Fosfatidilcolinas/metabolismo , Fosfolipases/análise , Fosfolipases/metabolismo , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Glândula Submandibular/efeitos dos fármacos , Temperatura
9.
Toxicon ; 27(4): 449-58, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2728031

RESUMO

Two phospholipases B (Vx I and Vx II) were purified from the venom of the Japanese yellow hornet, Vespa xanthoptera, by sequential chromatography on Sephadex G-100, SP-Sephadex and Mono S columns. They are very similar to each other in molecular and enzymatic properties, though the specific activity of Vx I was one-fifth that of Vx II. They hydrolyze the acyl ester bonds at the 1-position of phosphatidylcholine and lysophosphatidylcholine, therefore, their enzymatic specificities were of the A1 and L1 types.


Assuntos
Venenos de Abelha/análise , Lisofosfolipase/análise , Fosfolipases/análise , Venenos de Vespas/análise , Aminoácidos/análise , Cromatografia em Gel , Concentração de Íons de Hidrogênio , Hidrólise , Focalização Isoelétrica , Lisofosfolipase/isolamento & purificação , Peso Molecular , Octoxinol , Fosfolipídeos/análise , Polietilenoglicóis/farmacologia , Especificidade por Substrato , Fatores de Tempo
10.
Artigo em Inglês | MEDLINE | ID: mdl-24908598

RESUMO

OBJECTIVE: To evaluate the expression of phospholipase (PL) and secreted aspartyl proteinase (SAP) by Candida glabrata and C tropicalis obtained from the denture biofilms of healthy participants (16 isolates), patients with oral candidiasis with diabetes (10 isolates), and patients with oral candidiasis without diabetes (25 isolates). STUDY DESIGN: After incubation, the supernatants and pellets of the isolates were used for the enzymatic assays and quantification of colony-forming units (CFU), respectively. Colorimetric tests were used with phosphatidylcholine as a substrate for PL and azocasein as a substrate for SAP, and the absorbances of the samples were measured. Enzymatic rates were calculated, and values were normalized by CFU. Results were analyzed with factorial analyses of variance (α = .05). RESULTS: C tropicalis and C glabrata were proteolytic and phospholipolytic. The clinical sources of isolates had no significant effect on the enzymatic activities (P > .05). C tropicalis had significantly higher enzymatic activity for both PL and SAP (P < .001) than did C glabrata. CONCLUSIONS: C tropicalis isolates produced significantly higher amounts of both enzymes than did the C glabrata isolates.


Assuntos
Candida/enzimologia , Candida/isolamento & purificação , Candidíase Bucal/microbiologia , Idoso , Meios de Cultura/química , Complicações do Diabetes/microbiologia , Feminino , Humanos , Técnicas In Vitro , Masculino , Técnicas Microbiológicas , Peptídeo Hidrolases/análise , Fosfolipases/análise
11.
J Endod ; 39(5): 605-11, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23611377

RESUMO

INTRODUCTION: Vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) are key players in vasculogenesis and are also involved in pathologic conditions with bone destruction. Vasculogenesis is critical for disease progression, and bone resorption is a hallmark of apical periodontitis. However, the localization of VEGFs and VEGFRs and their gene signaling pathways in human apical periodontitis have not been thoroughly investigated. The aim of this study was to localize VEGFs and VEGFRs and analyze their gene expression as well as signaling pathways in human periapical lesions. METHODS: Tissue was collected after endodontic surgery from patients diagnosed with chronic apical periodontitis. Periodontal ligament samples from extracted healthy wisdom teeth was also collected and used as control tissue. In lesion cryosections, VEGFs/VEGFRs were identified by immunohistochemistry/double immunofluorescence by using specific antibodies. A human VEGF signaling polymerase chain reaction array system was used for gene expression analysis comparing lesions with periodontal ligament samples. RESULTS: The histologic evaluation revealed heterogeneous morphology of the periapical lesions with various degrees of inflammatory infiltrates. In the lesions, all investigated factors and receptors were identified in blood vessels and various immune cells. No lymphatic vessels were detected. Gene expression analysis revealed up-regulation of VEGF-A and VEGFR-3, although not significant. Phosphatidylinositol-3-kinases, protein kinase C, mitogen-activated protein kinases, and phospholipases, all known to be involved in VEGF-mediated angiogenic activity, were significantly up-regulated. CONCLUSIONS: The cellular and vascular expressions of VEGFs and VEGFRs in chronic apical periodontitis, along with significant alterations of genes mediating VEGF-induced angiogenic responses, suggest ongoing vascular remodeling in established chronic periapical lesions.


Assuntos
Periodontite Periapical/patologia , Receptores de Fatores de Crescimento do Endotélio Vascular/análise , Transdução de Sinais/fisiologia , Fator A de Crescimento do Endotélio Vascular/análise , Perda do Osso Alveolar/patologia , Linfócitos B/patologia , Vasos Sanguíneos/patologia , Progressão da Doença , Humanos , Linfócitos/patologia , Macrófagos/patologia , Proteínas Quinases Ativadas por Mitógeno/análise , Necrose , Neovascularização Patológica/patologia , Neutrófilos/patologia , Ligamento Periodontal/patologia , Fosfatidilinositol 3-Quinase/análise , Fosfolipases/análise , Proteína Quinase C/análise , Receptores de Fatores de Crescimento do Endotélio Vascular/fisiologia , Linfócitos T/patologia , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/fisiologia , Fator C de Crescimento do Endotélio Vascular/análise , Fator D de Crescimento do Endotélio Vascular/análise , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/análise
12.
J. appl. oral sci ; 25(3): 274-281, May-June 2017. tab, graf
Artigo em Inglês | LILACS, BBO - odontologia (Brasil) | ID: biblio-893617

RESUMO

Abstract Pulpal and periodontal tissues have similar microbiota that allows cross-contamination between the pulp and periodontal tissues. Objective The aim of this study was to investigate the prevalence of isolated Candida albicans from periodontal endodontic lesions in diabetic and normoglycemic patients, and the fungi's virulence in different atmospheric conditions. Material and Methods A case-control study was conducted on 15 patients with type 2 diabetes mellitus (G1) and 15 non-diabetics (G2) with periodontal endodontic lesions. Samples of root canals and periodontal pockets were plated on CHROMagar for later identification by polymerase chain reaction (PCR) and virulence test. Results C. albicans was identified in 79.2% and 20.8% of the 60 samples collected from diabetic and normoglycemic patients, respectively. Of the 30 samples collected from periodontal pockets, 13 showed a positive culture for C. albicans, with 77% belonging to G1 and 23% to G2. Of the 11 positive samples from root canals, 82% were from G1 and 18% from G2. Production of proteinase presented a precipitation zone Pz<0.63 of 100% in G1 and 72% in G2, in redox and negative (Pz=1), under anaerobic conditions in both groups. Hydrophobicity of the strains from G1 indicated 16.4% with low, 19.3% with moderate, and 64.3% with high hydrophobicity in redox. In G2, 42.2% had low, 39.8% had moderate, 18% had high hydrophobicity in redox. In anaerobic conditions, G1 showed 15.2% with low, 12.8% with moderate, and 72% with high hydrophobicity; in G2, 33.6% had low, 28.8% had moderate, and 37.6% had high hydrophobicity. There was statistical difference in the number of positive cultures between G1 and G2 (p<0.05) with predominance in G1. There was statistical difference for all virulence factors, except hemolysis (p=0.001). Conclusions Candida albicans was isolated more frequently and had higher virulence in diabetic patients.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Doenças Periodontais/microbiologia , Candida albicans/isolamento & purificação , Candida albicans/patogenicidade , Doenças da Polpa Dentária/microbiologia , Diabetes Mellitus Tipo 2/microbiologia , Oxirredução , Peptídeo Hidrolases/análise , Doenças Periodontais/fisiopatologia , Doenças Periodontais/diagnóstico por imagem , Bolsa Periodontal/microbiologia , Fosfolipases/análise , Virulência , DNA Fúngico , Radiografia Dentária , Estudos de Casos e Controles , Reação em Cadeia da Polimerase , Estatísticas não Paramétricas , Cavidade Pulpar/microbiologia , Doenças da Polpa Dentária/fisiopatologia , Doenças da Polpa Dentária/diagnóstico por imagem , Diabetes Mellitus Tipo 2/fisiopatologia , Eletroforese , Interações Hidrofóbicas e Hidrofílicas
14.
Gerodontology ; 25(4): 229-36, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18312370

RESUMO

MATERIAL AND METHODS: Fifty nine elders wearing complete dentures and living in retirement homes in Curitiba (southern Brazil), were divided into two groups: group #1, 26 patients with denture-induced stomatitis and group #2, 33 patients without denture-induced stomatitis. The two groups were evaluated in relation to the degree of denture-induced stomatitis, salivary fungal loads, and secretion of some histolytic enzymes. RESULTS: Patients from group #1 showed higher degrees of colonisation by Candida albicans (p = 0.031). Candida krusei, Candida tropicalis, and Candida parapsilosis were also isolated, but there were no differences between the groups (p > 0.05). Secretory aspartyl protease (Sap) and chondroitinase did not show significant differences among the isolated Candida spp. in the two groups. Phospholipase secretion rates were higher among the strains of C. albicans from group #2 (p = 0.036). The same behaviour was not detected for non-albicans Candida species. CONCLUSIONS: The results could infer that differences in the secretion rates of candidal histolytic enzymes should not be imputed as imperative for the progress of denture-induced stomatitis.


Assuntos
Candida/enzimologia , Proteínas Fúngicas/fisiologia , Instituição de Longa Permanência para Idosos , Hidrolases/fisiologia , Aposentadoria , Estomatite sob Prótese/microbiologia , Idoso , Ácido Aspártico Endopeptidases/análise , Candida/classificação , Candida albicans/enzimologia , Candida tropicalis/enzimologia , Condroitinases e Condroitina Liases/análise , Contagem de Colônia Microbiana , Prótese Total/microbiologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Hidrolases/análise , Masculino , Fosfolipases/análise , Saliva/microbiologia , Fatores Sexuais , Virulência
15.
Mycoses ; 50(5): 407-11, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17714362

RESUMO

This investigation was designed to evaluate the frequency of erythematous candidosis (EC) and Candida species, proteinase and phospholipase exoenzyme production, and to compare clinical features in patients with complete dentures and HIV+/Acquired Immunodeficiency Disease Syndrome (AIDS). Fifty-one patients were selected from a total of 285 with EC: denture wearers (n = 30) and HIV+/AIDS (n = 21). The yeast prevalence and the production of exoenzymes, such as proteinase and phospholipase by Candida species were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) electrophoresis. The frequency of Candida albicans was significantly higher (P < 0.05) in both groups although other yeast species (Candida glabrata, Candida krusei, Candida parapsilosis, Candida guilliermondi and Candida tropicalis) were also found. Candida albicans showed greater levels of proteinase production in the denture wearers, when compared with the HIV+/AIDS group. There was no difference between groups with regard to phospholipase production. The protein bands presented similar molecular weights, showing the presence of proteinases in both groups. It could be concluded that the clinical manifestation of EC may be related to its proteinase production capacity. Combination therapies using proteinase inhibitors play an important role in inhibiting exoenzyme production by Candida species, mainly C. albicans.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Candida/isolamento & purificação , Candidíase Bucal/epidemiologia , Candidíase Bucal/microbiologia , Prótese Total/microbiologia , Infecções por HIV/epidemiologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/microbiologia , Brasil/epidemiologia , Candida/classificação , Comorbidade , Prótese Total/estatística & dados numéricos , Eletroforese em Gel de Poliacrilamida , Endopeptidases/análise , Endopeptidases/isolamento & purificação , Feminino , Infecções por HIV/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Boca/microbiologia , Técnicas de Tipagem Micológica , Fosfolipases/análise , Fosfolipases/isolamento & purificação , Prevalência
16.
Clin Exp Allergy ; 36(8): 1078-86, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16911364

RESUMO

BACKGROUND: Hevea brasiliensis latex serum is commonly used as the in vivo and in vitro reference antigen for latex allergy diagnosis as it contains the full complement of latex allergens. OBJECTIVE: This study quantifies the concentrations of the significant allergens in latex serum and examines its suitability as an antigen source in latex allergy diagnosis and immunotherapy. METHODS: The serum phase was extracted from centrifuged latex that was repeatedly freeze-thawed or glycerinated. Quantitation of latex allergens was performed by two-site immunoenzymetric assays. The abundance of RNA transcripts of the latex allergens was estimated from the number of their clones in an Expressed Sequence Tags library. RESULTS: The latex allergens, Hev b 1, 2, 3, 4, 5, 6, 7 and 13, were detected in freeze-thawed and glycerinated latex serum at levels ranging from 75 (Hev b 6) to 0.06 nmol/mg total proteins (Hev b 4). Hev b 6 content in the latex was up to a thousand times higher than the other seven latex allergens, depending on source and/or preparation procedure. Allergen concentration was reflected in the abundance of mRNA transcripts. When used as the antigen, latex serum may bias the outcome of latex allergy diagnostic tests towards sensitization to Hev b 6. Tests that make use of latex serum may fail to detect latex-specific IgE reactivity in subjects who are sensitized only to allergens that are present at low concentrations. CONCLUSION: Latex allergy diagnostics and immunotherapy that use whole latex serum as the antigen source may not be optimal because of the marked imbalance of its constituent allergens.


Assuntos
Alérgenos/análise , Hevea , Hipersensibilidade ao Látex/diagnóstico , Proteínas de Plantas/imunologia , Borracha/química , Alérgenos/genética , Alérgenos/imunologia , Antígenos de Plantas/análise , Antígenos de Plantas/genética , Antígenos de Plantas/imunologia , Etiquetas de Sequências Expressas , Biblioteca Gênica , Humanos , Imunoglobulina E/sangue , Hipersensibilidade ao Látex/imunologia , Fosfolipases/análise , Fosfolipases/genética , Fosfolipases/imunologia , Proteínas de Plantas/análise , Proteínas de Plantas/genética , RNA Mensageiro/análise , Sensibilidade e Especificidade , Testes Cutâneos
17.
Braz. j. microbiol ; 41(1): 19-23, Jan.-Mar. 2010. tab
Artigo em Inglês | LILACS | ID: lil-531728

RESUMO

Patients suffering of diseases that affect central nervous system may be considered more susceptible to the infectious diseases of mouth. Sixty-nine patients suffering of cerebral palsy, Down's syndrome and metal retardation were submitted to saliva examination for the presence of Candida spp. before and after a procedure of dental cleaning. The isolates were submitted to assay for verifying phospholipase production. 55.10 percent of the patients provided isolation of Candida spp. The frequency of isolation obtained before dental procedure was: C. albicans (83.33 percent), C. krusei (8.33 percent) and C. kefyr, C. parapsilosis and C. glabrata (2.78 percent each). The frequency after the procedure was: C. albicans (68.57 percent), C. parapsilosis (11.43 percent), C. krusei and C. kefyr (8.57 percent each) and Candida glabrata (2.86 percent). We verified significantly difference (p < 0.01) between populations obtained at the two examinations. Phospholipase production was verified only among C. albicans strains and the proportion of producers was higher when testing isolates obtained after dental cleaning procedure. Studies focused on Candida spp. isolation are useful for better comprehension of the role of these yeasts on the oral flora from patients with cerebral palsy, Down's syndrome and metal retardation.


Assuntos
Humanos , Criança , Candidíase Bucal , Paralisia Cerebral , Candida/isolamento & purificação , Síndrome de Down , Fosfolipases/análise , Fosfolipases/isolamento & purificação , Deficiência Intelectual , Escovação Dentária , Técnicas e Procedimentos Diagnósticos , Epidemiologia , Métodos
18.
Anal Biochem ; 221(1): 152-9, 1994 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-7985786

RESUMO

A versatile continuous fluorometric assay for phospholipases A2, C, and D has been developed utilizing polymerized mixed liposomes made of pyrene-containing phospholipids (5 mol%) uniformly inserted in the polymerized liposomes of 1,2-bis[12-(lipoyloxy)dodecanoyl]-sn-glycero-3-phosphoglycerol (BLPG) and its derivatives. 1-Hexadecanoyl-2-(1-pyrenedecanoyl)-sn-glycero-3-phosphocholine was used for phospholipase A2 and N-(1-pyrenesulfonyl)-egg phosphatidyl ethanolamine for phospholipases C and D. Fluorescence emission of pyrene moieties in polymerized mixed liposomes was strongly quenched by BLPG molecules and, thus, the hydrolysis of pyrene-containing phospholipids and the subsequent displacement of pyrene moieties from the liposomes resulted in a large increase in fluorescence intensity. All the phospholipases tested selectively and rapidly hydrolyzed the inserted pyrene-containing phospholipids, which were readily monitored by measuring an increase in fluorescence emission at 380 nm. Assay conditions for individual phospholipases were optimized by altering interfacial properties of polymerized liposomes, such as surface charge, and subsequently by changing the chemical structure of hydrolyzable phospholipids. Phospholipase activities were linearly proportional to enzyme concentrations in the range from 0.1 to 50 ng. Specific activity determined for phospholipases from a wide variety of sources ranged from 0.5 to 100 mumol/min/mg. Polymerized mixed liposomes are exceptionally stable against chemical and physical degradation and the assay requires only a small amount of pyrene-containing phospholipids. In addition, the polymerized matrix of BLPG (and its derivatives), due to its inertness to the phospholipase hydrolysis, allows the direct measurement of the equilibrium dissociation constant for a protein-liposome complex.


Assuntos
Fosfolipases/análise , Fluorometria , Hidrólise , Lipossomos , Polímeros
19.
Anal Biochem ; 154(2): 676-81, 1986 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-3755302

RESUMO

A rapid method for the assay of phospholipase A2 has been developed using a radioactive substrate, L-alpha-dipalmitoyl-(2-[9,10(N)-3H]palmitoyl)-phosphatidylcholine. The substrate diluted with cold carrier (1 mM) is dissolved in 80% ethanol containing 25 mM sodium deoxycholate. The enzymatic reaction is performed in 1.0 ml 0.1 M glycine-NaOH buffer, pH 9.0, containing 2 mumol CaCl2, 10 micrograms bovine serum albumin, 2.5 mumol sodium deoxycholate, 0.01 unit (or less) phospholipase A2, and 40-100 nmol substrate. The enzymatic reaction is terminated by adding 0.2 ml 5% Triton X-100 solution containing 40 mumol EDTA. The product of the enzymatic reaction, radioactive palmitic acid, is extracted by 10 ml hexane containing 0.1% acetic acid in the presence of anhydrous sodium sulfate (0.5 g/ml). Activity of phospholipase A2 is directly determined from the radioactivity in the hexane extract. The present method achieves a quick separation of the radioactive product, [3H]palmitic acid, from the radioactive substrate, L-alpha-dipalmitoyl-(2-[3H]palmitoyl)-phosphatidylcholine, without the need of separation by TLC.


Assuntos
Fosfolipases A/análise , Fosfolipases/análise , 1-Propanol , Cromatografia em Camada Fina , Ácido Desoxicólico , Hexanos , Marcação por Isótopo , Octoxinol , Ácido Palmítico , Ácidos Palmíticos/isolamento & purificação , Fosfolipases A2 , Polietilenoglicóis , Surfactantes Pulmonares/metabolismo , Ácido Silícico , Especificidade por Substrato , Trítio , Água
20.
Can J Microbiol ; 28(6): 672-8, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6811121

RESUMO

Treponema require long-chain fatty acids for growth in vitro. Serum, added to culture media, provides a source of long-chain fatty acids. These fatty acids, however, are esterified to triglycerides, phospholipids, and cholesterol. In this study, the major pathways of complex lipid catabolism in T. phagedenis, T. denticola, T. refringens, T. minutum, and T. vincentii were investigated. Lipase activity was demonstrated in five Treponema species using four lipid substrates. Chromatographic data demonstrated that, during growth, treponemes completely utilized lysophosphatidylcholine, present in serum-supplemented culture media, while phosphatidylcholine and phosphatidylinositol were not utilized. Phospholipase B and glycerophosphorylcholine diesterase activities were demonstrated in the five species of Treponema studied. Treponema phagedenis and T. denticola had phosphatase activity, while T. refringens, T. minutum, and T. vincentii did not have an acid phosphatase activity. Phospholipase A, C, and D and alkaline phosphatase activities were not found in five species of Treponema. Based on the enzymes demonstrated in this study, two pathways of phospholipid catabolism are proposed.


Assuntos
Metabolismo dos Lipídeos , Lisofosfolipídeos , Treponema/metabolismo , Fosfatase Ácida/análise , Fosfatase Alcalina/análise , Glicerolfosfato Desidrogenase/análise , Glicerofosfatos/metabolismo , Lipase/análise , Fosfatidilgliceróis/metabolismo , Fosfolipases/análise , Fosfolipídeos/metabolismo
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