RESUMEN
Streptococcus sanguinis is an important cause of infective endocarditis. In strain SK36, the ABC-family manganese transporter, SsaACB, is essential for virulence. We have now identified a ZIP-family protein, TmpA, as a secondary manganese transporter. A tmpA mutant had no phenotype, but a ΔssaACB ΔtmpA mutant was more attenuated for serum growth and for virulence in a rabbit model than its ΔssaACB parent. The growth of both mutants was restored by supplemental manganese, but the ΔssaACB ΔtmpA mutant required twenty-fold more and accumulated less. Although ZIP-family proteins are known for zinc and iron transport, TmpA-mediated transport of either metal was minimal. While ssaACB appears ubiquitous in St. sanguinis, tmpA was present in a majority of strains and a mntH gene encoding an NRAMP-family transporter was identified in relatively few, including VMC66. As in SK36, deletion of ssaACB greatly diminished VMC66 endocarditis virulence and serum growth, and deletion of tmpA from this mutant diminished virulence further. Virulence was not significantly altered by deletion of mntH from either VMC66 or its ΔssaACB mutant. This and the accompanying paper together suggest that SsaACB is of primary importance for endocarditis virulence while secondary transporters TmpA and MntH contribute to growth under differing conditions.
Asunto(s)
Endocarditis Bacteriana , Endocarditis , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Manganeso/metabolismo , Conejos , Streptococcus sanguis/metabolismo , VirulenciaRESUMEN
This study's objective was to examine L-arginine (L-arg) supplementation's effect on mono-species biofilm (Streptococcus mutans/Streptococcus sanguinis) growth and underlying enamel substrates. The experimental groups were 1%, 2%, and 4% arg, and 0.9% NaCl was used as the vehicle control. Sterilised enamel blocks were subjected to 7-day treatment with test solutions and S. mutans/S. sanguinis inoculum in BHI. Post-treatment, the treated biofilms stained for live/dead bacterial cells were analysed using confocal microscopy. The enamel specimens were analysed using X-ray diffraction crystallography (XRD), Raman spectroscopy (RS), and transmission electron microscopy (TEM). The molecular interactions between arg and MMP-2/MMP-9 were determined by computational molecular docking and MMP assays. With increasing arg concentrations, bacterial survival significantly decreased (p < 0.05). The XRD peak intensity with 1%/2% arg was significantly higher than with 4% arg and the control (p < 0.05). The bands associated with the mineral phase by RS were significantly accentuated in the 1%/2% arg specimens compared to in other groups (p < 0.05). The TEM analysis revealed that 4% arg exhibited an ill-defined shape of enamel crystals. Docking of arg molecules to MMPs appears feasible, with arg inhibiting MMP-2/MMP-9 (p < 0.05). L-arginine supplementation has an antimicrobial effect on mono-species biofilm. L-arginine treatment at lower (1%/2%) concentrations exhibits enamel hydroxyapatite stability, while the molecule has the potential to inhibit MMP-2/MMP-9.
Asunto(s)
Antibacterianos/farmacología , Arginina/farmacología , Durapatita/farmacología , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Antibacterianos/química , Arginina/química , Relación Dosis-Respuesta a Droga , Durapatita/química , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Inhibidores de la Metaloproteinasa de la Matriz/química , Pruebas de Sensibilidad Microbiana , Streptococcus mutans/efectos de los fármacos , Streptococcus sanguis/efectos de los fármacosRESUMEN
Nonnutritive sweeteners (NNSs) are sugar substitutes widely used to reduce the negative health effects of excessive sugar consumption. Dental caries, one of the most prevalent chronic diseases globally, results from a pathogenic biofilm with microecological imbalance and frequent exposure to sugars. Some research has shown that certain NNSs possess less cariogenic potential than sucrose, indicating their putative effect on oral microbiome. To uncover the alterations of acidogenic pathogens and alkali-generating commensals, as well as the biofilm cariogenic potential under the influence of NNSs, we selected four common NNSs (acesulfame-K, aspartame, saccharin, and sucralose) and established single-, dual-, and multispecies in vitro culture model to assess their effects on Streptococcus mutans (S. mutans) and/or Streptococcus sanguinis (S. sanguinis) compared to sucrose with the same sweetness. The results showed that NNSs significantly suppressed the planktonic growth, acid production, and biofilm formation of S. mutans or S. sanguinis compared with sucrose in single-species cultures. Additionally, decreased S. mutans/S. sanguinis ratio, less EPS generation, and higher pH value were observed in dual-species and saliva-derived multispecies biofilms with supplementary NNSs. Collectively, this study demonstrates that NNSs inhibit the cariogenic potential of biofilms by maintaining microbial equilibrium, thus having a promising prospect as anticaries agents.
Asunto(s)
Caries Dental/prevención & control , Diterpenos de Tipo Kaurano/química , Microbiota , Boca/microbiología , Edulcorantes no Nutritivos , Aspartame/análisis , Biopelículas/efectos de los fármacos , Cariogénicos/farmacología , Caries Dental/etiología , Glicósidos/metabolismo , Humanos , Hibridación Fluorescente in Situ , Proteínas de Plantas/química , Sacarina/análisis , Streptococcus mutans , Streptococcus sanguis , Sacarosa/análogos & derivados , Sacarosa/análisis , Tiazinas/análisisRESUMEN
Piper betle var. nigra is a tropical plant closely related to the common piper. P. betle has also been dubbed a promising source of natural antioxidants in herbal health products, antibacterial, antifungal, antimalarial, cytotoxic activity against the cancer cell lines K562 and HL-60, and antileishmanial. The aim of this study to observation Antimicrobial activity and isolation of chemical compound. The antimicrobial activity of P. betle extract was performed by well diffusion method against two oral pathogenic bacteria (Streptococcus mutans and Streptococcus sanguinis) and opportunistic pathogenic yeast (Candida albicans). The inoculum (bacterial and yeast suspension) was prepared from a 24-h culture on NB for bacterial suspension and on TSB for yeast suspension. Extraction and isolation using various method of chromatography. Isolated compounds were characterized by spectroscopic means. Our study showed antimicrobial activity from crude ethanol extract of leaves P. betle L. var. nigra against two oral pathogenic bacteria and opportunistic pathogenic yeast with concentration 0.5% and 1%. The first report of two new amides derivatives, piperenamide A (1) and piperenamide B (2) in P. betle L. var. nigra.
Asunto(s)
Amidas/análisis , Antiinfecciosos/análisis , Piper betle/química , Hojas de la Planta/química , Amidas/farmacología , Antiinfecciosos/farmacología , Candida albicans/efectos de los fármacos , Candidiasis/tratamiento farmacológico , Humanos , Indonesia , Extractos Vegetales/análisis , Extractos Vegetales/farmacología , Infecciones Estreptocócicas/tratamiento farmacológico , Streptococcus mutans/efectos de los fármacos , Streptococcus sanguis/efectos de los fármacosRESUMEN
Untreated dental caries is the most prevalent disease worldwide. Development of caries is associated with the intake of sugar. The microorganisms utilize the sugar and create an acidic environment, which results in mineral loss. The appropriate use of fluoride is associated with a decline of caries. Another approach in preventing caries might be the increase of pH in dental plaque. During recent years, arginine has increasingly become the focus of interest. This is based on the fact that certain streptococci possess an arginine deiminase system (ADS) which metabolizes free arginine. In vivo, the incidence of caries was inversely correlated with ADS activity in saliva and dental plaque. ADS is highly active in Streptococcus gordonii and S. sanguinis, but is absent in S. sobrinus and S. mutans. In the presence of 1.5% L-arginine, S. gordonii and S. sanguinis, but not S. mutans and S. sobrinus, synthesize the metabolite citrulline and increase the pH of the environment.In defined multispecies biofilms consisting of ADS-positive and ADS-negative streptococci, supplementation with 1.5% arginine suppressed the growth of ADS-negative by favoring ADS-positive streptococci together with an increase in the pH of the environment. Evaluating the influence of daily manual removal of the biofilm in vitro by brushing with a commercial toothpaste containing fluoride and arginine resulted in less surface microhardness even when compared with a toothpaste with fluoride only. Recent studies clinically investigated the effect of using an arginine-containing dentifrice and reported a decrease of DMFS by about 10-20%.
Asunto(s)
Caries Dental , Arginina , Biopelículas , Caries Dental/prevención & control , Humanos , Streptococcus mutans , Streptococcus sanguisRESUMEN
BACKGROUND: Streptococcus mutans and Streptococcus sanguinis are Gram-positive bacteria that cause dental caries. MurA enzyme acts as a catalyst in the formation of peptidoglycan in bacterial cell walls, making it ideal as an antibacterial target. Basil (Ocimum americanum) is an edible plant that is diverse and has been used as a herbal medicine for a long time. It has been reported that basil has a pharmacological effect as well as antibacterial activity. The purpose of this study was to identify antibacterial compounds in O. americanum and analyze their inhibition activity on MurA enzyme. METHODS: Fresh leaves from O. americanum were extracted with n-hexane and purified by a combination of column chromatography on normal and reverse phases together with in vitro bioactivity assay against S. mutans ATCC 25175 and S. sanguinis ATCC 10556, respectively, while in silico molecular docking simulation of lauric acid (1) was conducted using PyRx 0.8. RESULTS: The structure determination of antibacterial compound by spectroscopic methods resulted in an active compound lauric acid (1). The in vitro evaluation of antibacterial activity in compound 1 showed Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values of 78.13 and 156.3 ppm and 1250 and 2500 ppm against S. sanguinis and S. mutans, respectively. Further analysis and in silico evaluation determined lauric acid (1) as MurA Enzyme inhibitor. Lauric acid (1) showed a binding affinity of -5.2 Kcal/mol, which was higher than fosfomycin. CONCLUSION: Lauric acid showed the potential as a new natural antibacterial agent through MurA inhibition in bacterial cell wall biosynthesis.
Asunto(s)
Antibacterianos/farmacología , Caries Dental/tratamiento farmacológico , Ácidos Láuricos/farmacología , Ocimum basilicum/química , Transferasas Alquil y Aril/antagonistas & inhibidores , Transferasas Alquil y Aril/metabolismo , Antibacterianos/aislamiento & purificación , Antibacterianos/uso terapéutico , Caries Dental/microbiología , Humanos , Ácidos Láuricos/aislamiento & purificación , Ácidos Láuricos/uso terapéutico , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Hojas de la Planta/química , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/enzimología , Streptococcus sanguis/efectos de los fármacos , Streptococcus sanguis/enzimologíaRESUMEN
Acylphloroglucinol meroterpenoids are adducts of the acylphloroglucinol unit and polyprenylated fragments (terpenoids) with attractive structures and bioactivities. During study of the medicinal molecules of the genus Hypericum, the first example of dimethylated acylphloroglucinol meroterpenoids with pyran-fused 6/6/6 tricyclic skeletons ((+)/(-)-elodeoidols A-F (1-6)), along with three biogenetical homologues (7-9) were isolated from the herbaceous plant of Hypericum elodeoides. Their structures including absolute configurations were then identified by nuclear magnetic resonance (NMR), high resolution electrospray ionization mass spectroscopy (HRESIMS), electronic circular dichroism (ECD) analysis and calculations. The monoterpene moiety of 1-6 were cyclized as two cyclohexanes and fused with a dimethylated acylphloroglucinol unit through an additional ether linkage, which led to an interesting pyran-fused linear or angle type 6/6/6 tricyclic skeleton. Compounds 5, 8 and 9 showed preferable antibacterial activities against three oral bacteria, among the MIC value of (+)-5 was 6.25 µg/ml; Compounds 3, 7 and 8 exhibited significant NO inhibitory activity against LPS induced RAW264.7 cells (IC50: 10.39 ± 0.49 ~ 34.25 ± 2.32 µM).
Asunto(s)
Antibacterianos/farmacología , Antiinflamatorios/farmacología , Hypericum/química , Óxido Nítrico/antagonistas & inhibidores , Floroglucinol/farmacología , Terpenos/farmacología , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Fusobacterium nucleatum/efectos de los fármacos , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Ratones , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Óxido Nítrico/biosíntesis , Floroglucinol/química , Floroglucinol/aislamiento & purificación , Células RAW 264.7 , Streptococcus mutans/efectos de los fármacos , Streptococcus sanguis/efectos de los fármacos , Relación Estructura-Actividad , Terpenos/química , Terpenos/aislamiento & purificaciónRESUMEN
BACKGROUND: Streptococcus sanguinis is Gram-positive bacteria that contribute to caries. Many antibacterial agents are resistant against bacteria so that the discovery of new antibacterial agents is a crucial issue. Mechanism of antibacterial agents by disrupting cell wall bacteria is a promising target to be developed. One of the enzymes contributing to the cell wall is MurA enzyme. MurA is an enzyme catalyzing the first step of peptidoglycan biosynthesis in the cell wall formation. Inhibiting MurA is an effective and efficient way to kill the bacteria. Source of bioactive compounds including the antibacterial agent can be found in natural product such as herbal plant. Piper betle L. was reported to contain active antibacterial compounds. However, there is no more information on the antibacterial activity and molecular mechanism of P. betle's compound against S. sanguinis. PURPOSE: The study aims to identify antibacterial constituents of P. betle L. and evaluate their activities through two different methods including in vitro and in silico analysis. MATERIALS AND METHODS: The antibacterial agent was purified by bioactivity-guided isolation with combination chromatography methods and the chemical structure was determined by spectroscopic methods. The in vitro antibacterial activity was evaluated by disc diffusion and dilution methods while the in silico study of a compound binds on the MurA was determined using PyRx program. RESULTS: The antibacterial compound identified as allylpyrocatechol showed inhibitory activity against S. sanguinis with an inhibition zone of 11.85 mm at 1%, together with MIC and MBC values of 39.1 and 78.1 µg/mL, respectively. Prediction for molecular inhibition mechanism of allylpyrocatechols against the MurA presented two allylpyrocatechol derivatives showing binding activity of -5.4, stronger than fosfomycin as a reference with the binding activity of -4.6. CONCLUSION: Two allylpyrocatechol derivatives were predicted to have a good potency as a novel natural antibacterial agent against S. sanguinis through blocking MurA activity that causes disruption of bacterial cell wall.
Asunto(s)
Transferasas Alquil y Aril/antagonistas & inhibidores , Antibacterianos/farmacología , Catecoles/farmacología , Inhibidores Enzimáticos/farmacología , Extractos Vegetales/farmacología , Streptococcus sanguis/efectos de los fármacos , Transferasas Alquil y Aril/metabolismo , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Catecoles/química , Catecoles/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Piper betle/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Streptococcus sanguis/enzimología , Relación Estructura-ActividadRESUMEN
Streptococcus sanguinis is an oral commensal bacterium, but it can colonize pre-existing heart valve vegetations if introduced into the bloodstream, leading to infective endocarditis. Loss of Mn- or Fe-cofactored virulence determinants are thought to result in weakening of this bacterium. Indeed, intracellular Mn accumulation mediated by the lipoprotein SsaB, a component of the SsaACB transporter complex, has been shown to promote virulence for endocarditis and O2 tolerance. To delineate intracellular metal-ion abundance and redox speciation within S. sanguinis, we developed a protocol exploiting two spectroscopic techniques, Inductively coupled plasma-optical emission spectrometry (ICP-OES) and electron paramagnetic resonance (EPR) spectroscopy, to respectively quantify total intracellular metal concentrations and directly measure redox speciation of Fe and Mn within intact whole-cell samples. Addition of the cell-permeable siderophore deferoxamine shifts the oxidation states of accessible Fe and Mn from reduced-to-oxidized, as verified by magnetic moment calculations, aiding in the characterization of intracellular metal pools and metal sequestration levels for Mn2+ and Fe. We have applied this methodology to S. sanguinis and an SsaACB knockout strain (ΔssaACB), indicating that SsaACB mediates both Mn and Fe uptake, directly influencing the metal-ion pools available for biological inorganic pathways. Mn supplementation of ΔssaACB returns total intracellular Mn to wild-type levels, but it does not restore wild-type redox speciation or distribution of metal cofactor availability for either Mn or Fe. Our results highlight the biochemical basis for S. sanguinis oxidative resistance, revealing a dynamic role for SsaACB in controlling redox homeostasis by managing the intracellular Fe/Mn composition and distribution.
Asunto(s)
Streptococcus sanguis , Factores de Virulencia , Hierro , Oxidación-Reducción , Streptococcus sanguis/genética , Streptococcus sanguis/metabolismo , Virulencia , Factores de Virulencia/metabolismoRESUMEN
The pyruvate oxidase (SpxB)-dependent production of H2O2 is widely distributed among oral commensal streptococci. Several studies confirmed the ability of H2O2 to antagonize susceptible oral bacterial species, including caries-associated Streptococcus mutans as well as several periodontal pathobionts. Here we report a potential mechanism to bolster oral commensal streptococcal H2O2 production by magnesium (Mg2+) supplementation. Magnesium is a cofactor for SpxB catalytic activity, and supplementation increases the production of H2O2 in vitro. We demonstrate that Mg2+ affects spxB transcription and SpxB abundance in Streptococcus sanguinis and Streptococcus gordonii. The competitiveness of low-passage commensal streptococcal clinical isolates is positively influenced in antagonism assays against S. mutans. In growth conditions normally selective for S. mutans, Mg2+ supplementation is able to increase the abundance of S. sanguinis in dual-species biofilms. Using an in vivo biophotonic imaging platform, we further demonstrate that dietary Mg2+ supplementation significantly improves S. gordonii oral colonization in mice. In summary, our results support a role for Mg2+ supplementation as a potential prebiotic to promote establishment of oral health-associated commensal streptococci.
Asunto(s)
Boca , Animales , Biopelículas , Peróxido de Hidrógeno , Magnesio , Ratones , Streptococcus gordonii , Streptococcus mutans , Streptococcus sanguisRESUMEN
OBJECTIVE: Psidium sp., Mangifera sp. and Mentha sp. and its mixture (PEM) are known to have antimicrobial and anti-adherence effects. DESIGN: Here, we have investigated these individual plant extracts and its synergistic mixture (PEM) for its anti-cariogenic effect to reduce populations of single and mixed-species of Streptococcus sanguinis and Streptococcus mutans in a planktonic or/and biofilm and their others reduced virulence. Bacterial populations in the biofilm after 24 h, hydrophobic cell surface activity to n-hexadecane and pH changes at 5 min' intervals until 90 min of incubation were recorded. Total phenolic content and bioactive compounds in the crude aqueous plant extracts were analysed. Regulatory gene expressions of S. mutans adhesins genes (gtfB, gtfC, gbpB and spaP) upon treatment with PEM were investigated in planktonic and biofilm conditions. RESULTS: All plant extracts strongly reduced S. mutans in the biofilm compared to S. sanguinis in single and mixed-species. PEM reduced S. mutans by 84% with S. sanguinis 87% in the mixed population. Psidium sp. and PEM highly reduced cell-surface hydrophobicity of the two bacteria thus reducing adherence and biofilm formation. PEM and Mangifera sp. lowered initial pH change in the mixed populations of S. sanguinis and S. mutans. PEM downregulated the S. mutans gtfB gene expression in the single species planktonic and mixed-species biofilms. CONCLUSIONS: The effectiveness of PEM in reducing S. mutans within the biofilm, cell-surface hydrophobicity, acid production and adhesin gene (gtfB) expression in mixed-species with S. sanguinis indicates its potential as an antibacterial agent against dental caries. This is attributed to the phenolic content in the PEM.
Asunto(s)
Biopelículas/efectos de los fármacos , Mangifera/química , Mentha/química , Extractos Vegetales/farmacología , Psidium/química , Ácidos/análisis , Adhesión Bacteriana/efectos de los fármacos , Genes Bacterianos , Concentración de Iones de Hidrógeno , Streptococcus/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Streptococcus sanguisAsunto(s)
Absceso Encefálico , Infecciones Estreptocócicas , Streptococcus sanguis/patogenicidad , Tálamo/patología , Adulto , Absceso Encefálico/diagnóstico por imagen , Absceso Encefálico/microbiología , Absceso Encefálico/patología , Absceso Encefálico/cirugía , Humanos , Masculino , Infecciones Estreptocócicas/diagnóstico por imagen , Infecciones Estreptocócicas/patología , Infecciones Estreptocócicas/cirugíaRESUMEN
Phenolic compounds in fruits such as cranberries have been shown to promote a number of biological activities. The purpose of this study was to investigate the effects of polyphenolic compound-containing lingonberry extract on oral streptococci and compare them with the known anti-cariogenic activity of cranberries. Water-soluble and polyphenol-rich fractions (Fractions I and II, respectively) were isolated from cranberries and lingonberries. The effects of those fractions on the biofilm formation ability and bioactivity of Streptococcus mutans MT8148R, Streptococcus sobrinus 6715, and Streptococcus sanguinis ATCC 10556 were then evaluated. Cranberry or lingonberry Fraction II (at 0.5-1 mg/ml) significantly reduced biofilm formation by S. mutans, S. sobrinus, and S. sanguinis. In contrast, cranberry or lingonberry Fraction I (at 0.5-2 mg/ml) increased biofilm formation by S. mutans and S. sobrinus, but not by S. sanguinis. Fractions I and II (at 1-2 mg/ml) also reduced the bioactivity of S. mutans, while Fraction II (at 0.5 mg/ml) enhanced the bioactivity of all tested strains. The results revealed that lingonberries contained a larger amount of polyphenol than cranberries and that they showed almost the same level of activity against the biofilm formation ability and bioactivity of oral streptococci. This indicates that polyphenol-rich lingonberry fraction offers a promising natural food derivative for prevention of dental caries.
Asunto(s)
Biopelículas/efectos de los fármacos , Frutas/química , Extractos Vegetales/farmacología , Streptococcus/efectos de los fármacos , Vaccinium vitis-Idaea/química , Pruebas de Sensibilidad Microbiana , Streptococcus mutans/efectos de los fármacos , Streptococcus sanguis/efectos de los fármacos , Streptococcus sobrinus/efectos de los fármacos , Vaccinium macrocarpon/químicaRESUMEN
Abstract There are several controversies regarding the efficacy of homeopathic substances; however, these remedies are used in many countries for the treatment of various pathological conditions. The purpose of this study was to evaluate the in vitro antibacterial activity of two homeopathic tinctures Arsenicum album (mineral extract) and Lycopodium clavatum (plant extract) on the periodontal bacteria Actinomyces israelii, Streptococcus sanguinis, Prevotella intermedia, Aggregatibacter actinomycetemcomitans and Phorphyromonas gingivalis (P. gingivalis). Materials and methods: Equal numbers of bacteria were seeded on agar plates containing enriched media with the homeopathic solutions at 1dH and 1cH dilutions. After 7 days of incubation under anaerobic conditions, colony forming units (CFUs) were counted. The antibacterial effect was calculated based on the total number of CFUs observed on non-tincture containing agar, and on the tincture containing plates. Results: No visible growth of any of the strains was observed on the plates containing Arsenicum album at any of the dilutions tested. In contrast, when Lycopodium clavatum at 1cH dilution was tested, only P. gingivalis was susceptible to this compound. Conclusions: The results suggest that the mineral extract tincture had a greater antibacterial activity than the plant extract tincture, also Lycopodium clavatum preparation could be an effective inhibitor of periodontal pathogens bacteria such as P. gingivalis.
Resumen Se necesita un mayor número de estudios in vitro e in vivo para validar estos resultados.
Asunto(s)
Streptococcus sanguis/efectos de los fármacos , Actinomyces/efectos de los fármacos , Arsenicum Album/antagonistas & inhibidores , Lycopodium clavatum/antagonistas & inhibidores , Aggregatibacter actinomycetemcomitans/efectos de los fármacos , Porphyromonas gingivalis/efectos de los fármacos , Prevotella intermedia/efectos de los fármacos , Extractos Vegetales/análisis , Farmacocinética del Medicamento Homeopático , HomeopatíaRESUMEN
OBJECTIVE: Titanium dioxide (TiO2) incorporation in biomaterials is a promising technology due to its photocatalytic and antibacterial activities. However, the antibacterial potential of different TiO2 crystalline structures on a multispecies oral biofilm remains unknown. We hypothesized that the different crystalline TiO2 phases present different photocatalytic and antibacterial activities. METHODS: Three crystalline TiO2 films were deposited by magnetron sputtering on commercially pure titanium (cpTi), in order to obtain four groups: (1) machined cpTi (control); (2) A-TiO2 (anatase); (3) M-TiO2 (mixture of anatase and rutile); (4) R-TiO2 (rutile). The morphology, crystalline phase, chemical composition, hardness, elastic modulus and surface free energy of the surfaces were evaluated. The photocatalytic potential was assessed by methylene blue degradation assay. The antibacterial activity was evaluated on relevant oral bacteria, by using a multispecies biofilm (Streptococcus sanguinis, Actinomyces naeslundii and Fusobacterium nucleatum) formed on the treated titanium surfaces (16.5h) followed by UV-A light exposure (1h) to generate reactive oxygen species production. RESULTS: All TiO2 films presented around 300nm thickness and improved the hardness and elastic modulus of cpTi surfaces (p<0.05). A-TiO2 and M-TiO2 films presented superior photocatalytic activity than R-TiO2 (p<0.05). M-TiO2 revealed the greatest antibacterial activity followed by A-TiO2 (≈99.9% and 99% of bacterial reduction, respectively) (p<0.001 vs. control). R-TiO2 had no antibacterial activity (p>0.05 vs. control). SIGNIFICANCE: This study brings new insights on the development of extra oral protocols for the photocatalytic activity of TiO2 in oral biofilm-associated disease. Anatase and mixture-TiO2 showed antibacterial activity on this oral bacterial biofilm, being promising surface coatings for dental implant components.
Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Materiales Biocompatibles Revestidos/farmacología , Titanio/farmacología , Actinomyces , Antibacterianos/química , Materiales Biocompatibles Revestidos/química , Módulo de Elasticidad , Fusobacterium nucleatum , Dureza , Ensayo de Materiales , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Procesos Fotoquímicos , Espectrometría por Rayos X , Streptococcus sanguis , Propiedades de Superficie , Titanio/química , Difracción de Rayos XRESUMEN
Antimicrobial photodynamic therapy (aPDT) has shown to exert a bactericidal effect against Streptococcus sanguinis and Streptococcus mutans. However, this efficacy has been reported for either type of bacteria separately. Bacterial suspensions of both strains, separately or together, were treated with concentrations of methylene blue (MB) and rose bengal (RB). Suspensions were irradiated with a light-emitting diode lamp (λ center at 625nm for MB and λ center at 515nm for RB) using a fluence of 18J/cm2. RB-aPDT at concentrations of 0.16-0.62 and 0.16-0.31µg/mL, and MB-aPDT at concentrations of 0.62-1.25 and 0.31-1.25µg/mL inhibited the growth of S. mutans and S. sanguinis respectively by 6 log10. In suspensions of both strains together, the same 6 log10 reduction in bacterial growth was achieved using the same concentrations of each photosensiziser. In conclusion, RB-aPDT and MB-aPDT appear to exert the same bactericidal effect against suspensions of S. sanguinis and S. mutans either for single strain treatment or for samples constituted by both bacteria mixed together. RB shows to be slightly more efficient than MB.
Asunto(s)
Azul de Metileno/farmacología , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Rosa Bengala/farmacología , Streptococcus mutans/efectos de los fármacos , Streptococcus sanguis/efectos de los fármacosRESUMEN
BACKGROUND: The rise in disease incidence, increased resistance of pathogenic bacteria to currently used antibiotics and chemotherapeutics, opportunistic infections in immunocompromised individuals, and financial considerations in developing countries necessitates alternate preventive and treatment strategies for oral diseases. OBJECTIVE: The objective of the study is to assess the antimicrobial efficacy of triple and quadruple combinations of Acacia nilotica (AN), Murraya koenigii (Linn.) (MKL) Sprengel, Eucalyptus (Euca), and Psidium guajava (PS) on primary plaque colonizers. MATERIALS AND METHODS: The phytochemicals in four plants were extracted using Soxhlet apparatus. The dried extracts were diluted with dimethyl sulfoxide (DMSO) to prepare stock solutions (100 mg/ml) of each plant. The triple and quadruple combinations were prepared after mixing equal quantities of stock solutions from each plant extracts. The antimicrobial efficacy testing was done on Streptococcus mutans, Streptococcus sanguis, and Streptococcus salivarius using agar well diffusion method. Chlorhexidine of 0.2% composition and DMSO were used as positive and negative controls, respectively. The mean diameter of inhibition zone between different categories was compared using one-way analysis of variance. RESULTS: The combination of AN + MKL Sprengel + Euca + PS produced the highest mean diameter of inhibition zone (23.5 ± 2.17 mm) against S. mutans. The combination of AN + MKL Sprengel + Euca produced the maximum antimicrobial efficacy against S. sanguis (19.83 ± 1.33). CONCLUSION: All the triple and quadruple combinations of the plant extracts offered antimicrobial benefits either superior or comparable to 0.2% chlorhexidine against S. mutans, S. sanguis, and S. salivarius.
Asunto(s)
Acacia , Placa Dental/tratamiento farmacológico , Placa Dental/microbiología , Eucalyptus , Murraya , Extractos Vegetales/farmacología , Psidium , Antiinfecciosos/farmacología , Combinación de Medicamentos , Técnicas In Vitro , Pruebas de Sensibilidad Microbiana , Streptococcus mutans/efectos de los fármacos , Streptococcus salivarius/efectos de los fármacos , Streptococcus sanguis/efectos de los fármacosRESUMEN
OBJECTIVE: Green tea (Gt), leafs of Camellia sinensis var. assamica, is widely consumed as healthy beverage since thousands of years in Asian countries. Chewing sticks (miswak) of Salvadora persica L. (Sp) are traditionally used as natural brush to ensure oral health in developing countries. Both Gt and Sp extracts were reported to have anti-bacterial activity against many dental plaque bacteria. However, their combination has never been tested to have anti-bacterial and anti-adherence effect against primary dental plaque colonizers, playing an initial role in the dental plaque development, which was investigated in this study. METHODS: Two-fold serial micro-dilution method was used to measure minimal inhibitory concentration (MIC) of aqueous extracts of Gt, Sp and their combinations. Adsorption to hexadecane was used to determine the cell surface hydrophobicity (CSH) of bacterial cells. Glass beads were used to mimic the hard tissue surfaces, and were coated with saliva to develop experimental pellicles for the adhesion of the primary colonizing bacteria. RESULTS: Gt aqueous extracts exhibited better anti-plaque effect than Sp aqueous extracts. Their combination, equivalent to 1/4 and 1/2 of MIC values of Gt and Sp extracts respectively, showed synergistic anti-plaque properties with fractional inhibitory concentration (FIC) equal to 0.75. This combination was found to significantly reduce CSH (p<0.05) and lower the adherence ability (p<0.003) towards experimental pellicles. CONCLUSION: Combination between Gt and Sp aqueous extracts exhibited synergistic anti-plaque activity, and could be used as a useful active agent to produce oral health care products.
Asunto(s)
Actinomyces viscosus/efectos de los fármacos , Placa Dental/microbiología , Extractos Vegetales/farmacología , Salvadoraceae/química , Streptococcus mitis/efectos de los fármacos , Streptococcus sanguis/efectos de los fármacos , Té/química , Actinomyces viscosus/fisiología , Antibacterianos/farmacología , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Película Dental/microbiología , Placa Dental/tratamiento farmacológico , Sinergismo Farmacológico , Pruebas de Sensibilidad Microbiana , Saliva/química , Streptococcus mitis/fisiología , Streptococcus sanguis/fisiologíaRESUMEN
BACKGROUND: Antimicrobial photodynamic therapy has been proposed as an alternative to suppress subgingival species. This results from the balance among Streptococcus sanguis, Streptococcus mutans and Candida albicans in the dental biofilm. Not all the photosensitizers have the same photodynamic effect against the different microorganims. The objective of this study is to compare in vitro the photodynamic effect of methylene blue (MB), rose Bengal (RB) and curcumin (CUR) in combination with white light on the cariogenic microorganism S. mutans, S. sanguis and C. albicans. RESULTS: Photodynamic therapy with MB, RB and CUR inhibited 6 log 10 the growth of both bacteria but at different concentrations: 0.31-0.62 µg/ml and 0.62-1.25 µg/ml RB were needed to photoinactivate S. mutans and S. sanguis, respectively; 1.25-2.5 µg/ml MB for both species; whereas higher CUR concentrations (80-160 µg/ml and 160-320 µg/ml) were required to obtain the same reduction in S. mutans and S. sanguis viability respectively. The minimal fungicidal concentration of MB for 5 log10 CFU reduction (4.5 McFarland) was 80-160 µg/ml, whereas for RB it ranged between 320 and 640 µg/ml. For CUR, even the maximum studied concentration (1280 µg/ml) did not reach that inhibition. Incubation time had no effect in all experiments. CONCLUSIONS: Photodynamic therapy with RB, MB and CUR and white light is effective in killing S. mutans and S. sanguis strains, although MB and RB are more efficient than CUR. C. albicans required higher concentrations of all photosensitizers to obtain a fungicidal effect, being MB the most efficient and CUR ineffective.
Asunto(s)
Antifúngicos/farmacología , Biopelículas/efectos de los fármacos , Caries Dental/microbiología , Fármacos Fotosensibilizantes/farmacología , Candida albicans/efectos de los fármacos , Curcumina/farmacología , Caries Dental/tratamiento farmacológico , Técnicas In Vitro , Azul de Metileno/farmacología , Fotoquimioterapia , Rosa Bengala/farmacología , Streptococcus mutans/efectos de los fármacos , Streptococcus sanguis/efectos de los fármacosRESUMEN
Iliopsoas muscle abscess is an uncommon condition, which has been growing in incidence. We describe a primary iliopsoas abscess by Streptococcus sanguis affecting an 81-year-old man cured by antibiotic therapy and aspiration procedure. The objective is to enhance the suspicion index about the iliopsoas abscess that may be mistaken for other causes of acute abdomen. The important diagnostic role of abdominal imaging studies is also emphasised.