58 research outputs found
Políticas públicas de saúde bucal no Mercosul: similaridades e discrepâncias em tempos de globalização / Public oral health policies in Mercosul: similarities and discrepancies in times of globalization
O Mercosul busca integração no Cone Sul, seus países possuem sistemas de saúde bem característicos. Intenta-se apresentar similaridades e discrepâncias das políticas públicas de saúde bucal. Trata-se de estudo descritivo de cunho documental e bibliográfico. Constatou-se que na Argentina o Programa Nacional de Saúde Bucal enfatiza ações de promoção da saúde e trabalho multiprofissional. No Brasil, o Programa Brasil Sorridente prioriza trabalho multiprofissional e ampliação do acesso. No Paraguai, o Volver a Sonreir e Paraguay Sonríe focam na equidade e promoção da saúde. No Uruguai, o Programa Nacional de Salud Bucal articula promoção, prevenção e assistência de forma integrada. Na Venezuela não há uma Política Nacional de Saúde Bucal bem caracterizada. Os países buscam alinhamento nos princípios da universalidade, equidade, integralidade e participação popular, com descentralização e trabalho em equipe multiprofissional. Há uma nítida necessidade de estudos que comprovem estas políticas
Evaluation of leguminous lectins activities against bacterial biofilm formation
Biofilms are composed by microbial cells that are irreversibly associated with a surface and enclosed in a matrix of polymeric material. Lectins are sugar binding proteins of non immune origin that agglutinate cells and ⁄ or precipitate glycoconjugate molecules. Due to their capacity to bind and recognize specific carbohydrates, lectins can be a potent tool in biofilm studies. The search for potential phytochemicals as anti-biofilm agents has become an active area of research, and these proteins can bind to the bacteria or prevent the interaction with the surface and consequently decrease biofilm formation.
Thus, the present work aims to evaluate in vitro the antibacterial activity of plant lectinsfrom Canavalia genus against a panel of bacteria of medical relevance, and to inspect their capacity to interfere on the initial adhesion events and biofilm formation.
The assays were carried out using different concentrations of leguminous lectins, isolated from Canavalia ensiformis (ConA), C. maritima (ConM) and C. boliviana (ConBol). The effect of lectins was tested on Klebsiella oxytoca ATCC13182, Pseudomonas aeruginosa ATCC10145, Staphylococcus epidermidis CECT231 and Staphylococcus aureus. The bacterial planktonic growth in the presence of the lectins was determined trough absorbance measurement at 640 nm. Adhesion and biofilm assays were performed in polystyrene plates, and chalenged with the three lectins. The biomass accumulated was quantified using crystal violet staining.
The results showed that ConA emerged as the most promising lectin since it clearly reduced the bacterial plankctonic growth, specially of the Gram+ strains, with MIC values ranging between 30 and 125 μg/mL. ConA also disturbed the initial adhesion events of all bacteria and disturbed the biofilm formation ability of the Staphylococcus species for all the concentrations tested. Concerning Gram- bacteria, its biofilm formation ability was only prejudiced with higher concentrations of the lectin. Therefore, the results seem to highlight that the antimicrobial activity of ConA was more noticeable in the disturbance of bacterial adhesion and biofilm formation than impairing planktonic growth.
In conclusion, our results show that lectins, an important class of natural products, possess promising antibiofilm activity, suggesting that they may have therapeutic potential for the pharmacological treatment of biofilm-associated infections.IBB-CEB, FCT (PTDC/SAU-ESA/64609/2006) and CAPE
Casbane diterpene as novel and natural antimicrobial agent against biofilm infections
Croton nepetaefolius is a plant native from northeastern Brazil and belongs to Euphorbiaceae family. The
essential oil of this plant is widely used in folk medicine from the treatment of gastrointestinal disorders to
the use as an antiseptic agent, with an antifungal action scientifically proven. The action of this plant has been
extensively explored by the scientific community, being the secondary metabolites, which are responsible
for their properties, alkaloids, diterpenes, and triterpenes. The aim of this study was to evaluate the ability
of the secondary metabolite, casbane diterpene (CD) (isolated of the species mentioned above), to inhibit
microbial growth and biofilm formation of several clinical relevant species (about 15 species among bacteria
and fungi). Minimal inhibitory concentration was assessed by the standard technique of microdilution and
biofilm inhibition was tested using microtiter plates with biomass quantification by crystal violet staining
method. It was found that the CD possessed biocidal and biostatic activity for the majority of the species
screened, with the minimal concentration active between 125 and 500 mg/L. Moreover, CD anti-biofilm action
was also observed for some of the species. In addition, it was noticed some biofilm formation inhibition even
when the planktonic growth was not significantly affected. In conclusion it can be speculated that casbane
diterpene shows potential to be a natural tool for the treatment of diseases caused by different infectious
microorganisms
Effect of algae and plant lectins on planktonic growth and biofilm formation in clinically relevant bacteria and yeasts
This study aimed to evaluate the abilities of plant and algae lectins to inhibit planktonic growth and biofilm formation in bacteria and yeasts. Initially, ten lectins were tested on Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella oxytoca, Pseudomonas aeruginosa, Candida albicans, and C. tropicalis at concentrations of 31.25 to 250 μg/mL. The lectins from Cratylia floribunda (CFL), Vatairea macrocarpa (VML), Bauhinia bauhinioides (BBL), Bryothamnion seaforthii (BSL), and Hypnea musciformis (HML) showed activities against at least one microorganism. Biofilm formation in the presence of the lectins was also evaluated; after 24 h of incubation with the lectins, the biofilms were analyzed by quantifying the biomass (by crystal violet staining) and by enumerating the viable cells (colony-forming units). The lectins reduced the biofilm biomass and/or the number of viable cells to differing degrees depending on the microorganism tested, demonstrating the different characteristics of the lectins. These findings indicate that the lectins tested in this study may be natural alternative antimicrobial agents; however, further studies are required to better elucidate the functional use of these proteins.This study was supported by the CAPES (Brazil) under the BEX NT 2052/11NT3 Project, by the IBB-CEB and FCT (Portugal), by the European Community Fund FEDER, and by the COMPETE Program under the auspices of the PTDC/SAU-ESA/646091/2006/FCOMP-01-0124-FEDER-007480 Project. Kyria Santiago Nascimento, Alexandre Holanda Sampaio, Benildo Sousa Cavada, and Edson Holanda Teixeira are Senior Fellows of CNPq. Mr. David Martin helped with the English editing of the paper that was also revised by AJE (American Journal Experts)
Prophylactic outcomes of casbane diterpene in Candida albicans and Candida glabrata biofilms
Biofilms are surface associated communities of microorganisms embedded within a self-produced extracellular
matrix and adhered on inert and biotic surfaces. These biological consortia are considered the most prevalent
growth form of microorganisms. Biofilm formation is a potent virulence factor for a number of Candida species,
as it confers significant tolerance to antimicrobial therapy, primarily by limiting the penetration of substances
through the biofilm matrix. Casbane Diterpenes (CD) belongs to the class of diterpenoids isolated from few
species of plants from Euphorbiaceae family with important anticancer and antibacterial activities.
So, the goal of this study was to assess the antibiofilm effect of a Casbane Diterpene isolated from the stalks of
Croton nepetaefolius against Candida albicans and Candida glabrata. Biofilms were developed within the 96-
well microtiterplates in the presence of the CD. After 24 hours of growth, 100 μL of cells suspensions (1 x 106
cells ml-1 in Nutrient Broth) and 100 μL of solution of CD (500 - 31.5 μg/mL) were pipetted into each well and
incubated for 24 h at 37ºC in an orbital shaker at 120 rpm. Biofilms formation was characterized by total
biomass, through crystal violet (CV), and number of viable cells, expressed as log CFU per cm2.
CD showed to be able to reduce the biofilm formation of C. albicans and C. glabrata. CD reduced C. albicans
biomass in 82, 64, 57 and 27 % at the concentrations of 500, 250, 125 and 62.5 μg/mL, respectively. C.
glabrata biomass was reduced in 68 and 26 % at 500 and 250 μg/mL. Regarding the number of viable cells
embedded in the yeast biofilms, CD at 500 and 250 μg/mL reduced 2 and 1 log of C. albicans biofilm CFUs,
and 2.5 and 1 log for C. glabrata, respectively. Regarding the high resistance and recalcitrance of Candida
biofilms to the traditional therapies, CD emerges as a good prophylactic alternative to be used alone or in
combination with other traditional drugs
Compositional analysis of cashew (Anacardium occidentale L.) peduncle bagasse ash and its in vitro antifungal activity against Fusarium species
Cashew (Anacardium occidentale L.) is a plant with a highly social and economic importance in the Northeast Region of Brazil. Cashew peduncle bagasse is one of the greatest sources of residues (90–94%) produced by the cashew agronomic industry. In this study, we prepared cashew peduncle bagasse ash and submitted it to compositional analysis and in vitro tests for antifungal activity against Fusarium species. This analysis indicated a crystallinity of around 73%, corresponding to the following soluble phases: potassium bicarbonate - KHCO3 (39.54%), potassium sulfate - K2SO4 (24.87%), and struvite-K - MgKPO4·6H2O (8.59%). The amorphous phases (around 27%) were identified as the insoluble fraction of the ash. The solution showed high antifungal activity against F. oxysporum, F. moniliforme and F. lateritium. The activity of this product was greater than that of Cercobin® (thiophanate-methyl), indicating that this material could possibly be used as a non-toxic antifungal agent.(Análise da composição das cinzas do bagaço do pedúnculo do cajú (Anacardium occidentale L.) e sua atividade antifúngica in vitro contra espécies de Fusarium.). O Cajueiro (Anacardium occidentale L.) é uma planta com uma grande importância social e econômica no Nordeste do Brasil. O bagaço do pedúnculo do caju é uma das maiores fontes de resíduos (90-94%) produzidos pela indústria cajueira. Neste estudo, foram preparadas cinzas do bagaço e submetidas à análise da composição e a testes de atividade antifúngica in vitro contra espécies de Fusarium. Esta análise indicou uma cristalinidade em torno de 73%, correspondendo às seguintes fases solúveis: bicarbonato de potássio - KHCO3 (39,54%), sulfato de potássio - K2SO4 (24,87%), e estruvita-K - MgKPO4 • 6H2O (8,59%). As fases amorfas (cerca de 27%) foram identificadas como a fração insolúvel de cinzas. A solução apresentou alta atividade antifúngica contra F. oxysporum, F. moniliforme e F. lateritium. Sua ação foi maior do que o Cercobin® (tiofanato metílico), indicando uma possível utilização como um agente antifúngico não tóxico
Antibacterial and antioxidant activities of Derriobtusone A isolated from Lonchocarpus obtusus
This study evaluated the effect of derriobtusone A, a flavonoid isolated from Lonchocarpus obtusus, on two important pathogenic bacteria, Staphylococcus aureus and Escherichia coli, as well as its antioxidant activity and toxicity. Planktonic growth assays were performed, and the inhibition of biofilm formation was evaluated. In addition, antioxidant activity was assessed by DPPH radical scavenging assay, ferrous ion chelating assay, ferric-reducing antioxidant power assay, and β-carotene bleaching assay. Toxicity was evaluated by the brine shrimp lethality test. Results showed that derriobtusone A completely inhibited the planktonic growth of S. aureus at 250 and 500 μg/mL; however, it did not have the same activity on E. coli. Derriobtusone A reduced the biomass and colony-forming unit (cfu) of S. aureus biofilm at concentrations of 250 and 500 μg/mL. In various concentrations, it reduced the biofilm biomass of E. coli, and, in all concentrations, it weakly reduced the cfu. Derriobtusone A showed highly efficient antioxidant ability in scavenging DPPH radical and inhibiting β-carotene oxidation. The compound showed no lethality to Artemia sp. nauplii. In conclusion, derriobtusone A may be an effective molecule against S. aureus and its biofilm, as well as a potential antioxidant compound with no toxicity.This study was supported by CAPES (Brazil) through the BEX NT 2052/11NT3 Project and by IBB-CEB and FCT (Portugal) and European Community Fund FEDER, through Program COMPETE, in the ambit of Project PTDC/SAU-ESA/646091/2006/FCOMP-01-0124-FEDER-007480. Otilia Deusdenia Loiola Pessoa, Benildo Sousa Cavada, and Edson Holanda Teixeira are Senior Fellows of CNPq. Mr. David Martin helped with the English editing of the paper
Casbane diterpene as a promising natural antimicrobial agent against biofilm-associated infections
Croton nepetaefolius is a native plant from northeastern Brazil that belongs to the Euphorbiaceae family. The biological action of this plant has been extensively explored, being the secondary metabolites responsible for its properties alkaloids, diterpenes, and triterpenes. This study aimed to evaluate the ability of casbane diterpene (CD), isolated from the ethanolic extract of C. nepetaefolius, to inhibit microbial growth and biofilm formation of several clinical relevant species (bacteria and yeasts). It was found that CD possessed biocidal and biostatic activity against the majority of the species screened, with minimal active concentrations ranging between 125 and 500 µg/mL. In addition, it was observed that biofilm formation was inhibited even when the planktonic growth was not significantly affected. In conclusion, CD showed potential to be a natural tool for the treatment of diseases caused by different infectious microorganismsThis study was supported by FUNCAP and CNPq (Brazil) and by FCT (Portugal) through the project PTDC/SAU-ESA/64609/2006
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