985 resultados para Oxyde d’indium dopé à l’étain (ITO)


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The aim of this study was to evaluate the antiseptic efficacy of rotary instrumentation associated with calcium hydroxide-based pastes prepared with different vehicles and antiseptics. Chronic periapical lesions were experimentally induced in 72 premolar root canals of four dogs. Under controlled asepsis, after initial microbiological sampling (A1), the root canals were instrumented using the ProFile system in conjunction with 5.25% sodium hypochlorite and the intracanal medication was placed. Four experimental groups were formed according to the pastes used: group 1- Calen (n=18), group 2- Calen+CPMC (n=20), group 3- Ca(OH)2 p.a.+ anaesthetic solution (n=16) and group 4- Ca(OH)2 p.a.+ 2% chlorhexidine digluconate (n=18). After 21 days, the pastes were removed; the canals were emptied and 96 hours later a second microbiological sample was obtained (A2). The incidence of positive microbiological cultures and the number of cfus in stages A1 and A2 were compared statistically by the Wilcoxon test while the influence of the different treatments in intracanal infection was evaluated by Kruskal-Wallis test at 5% significance level (p<0.05). Large numbers of strict and facultative anaerobes, and viridans group streptococci were found in 100% of root canals of A1 samples. Among A2 samples, all treatments showed significant reduction of cfus and positive cultures (p<0.05), but only groups 3 and 4 showed 100% of root canals free of microorganisms. Rotary instrumentation plus NaOCl 5.25% associated with intracanal medication produced a drastic reduction or elimination of intracanal microbiota, whose performance was not influenced by the nature of the vehicle or the antiseptic added to the Ca(OH)2 p.a.

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OBJECTIVE: The purpose of this study was to evaluate the distribution of microorganisms in the root canal system (RCS) and periapical lesions of dogs' teeth after rotary instrumentation and placement of different calcium hydroxide [Ca(OH)2]-based intracanal dressings. MATERIALS AND METHODS: Chronic periapical lesions were experimentally induced in 80 premolar roots of four dogs. Instrumentation was undertaken using the ProFile rotary system and irrigation with 5.25% sodium hypochlorite. The following Ca(OH) 2-based pastes were applied for 21 days: group 1 - Calen (n=18); group 2 - Calen+CPMC (n=20); group 3 - Ca(OH)2 p.a. + anaesthetic solution (n=16) and group 4 - Ca(OH)2 p.a.+ 2% chlorhexidine digluconate (n=18). Eight root canals without endodontic treatment constituted the control group. Histological sections were obtained and stained with Brown & Brenn staining technique to evaluate the presence of microorganisms in the main root canal, ramifications of the apical delta and secondary canals, apical cementoplasts, dentinal tubules, areas of cemental resorption and periapical lesions. The results were analyzed statistically by the Mann-Whitney U test (p<0.05). RESULTS: The control group showed the highest prevalence of microorganisms in all sites evaluated. Gram-positive cocci, bacilli and filaments were the most frequent morphotypes. Similar microbial distribution patterns in the RCS and areas of cementum resorption were observed in all groups (p>0.05). The percentage of RCS sites containing microorganisms in groups 1, 2, 3, 4 and control were: 67.6%, 62.5%, 78.2%, 62.0% and 87.6%, respectively. CONCLUSION: In conclusion, the histomicrobiological analysis showed that the rotary instrumentation and the different calcium hydroxide pastes employed did not effectively eliminate the infection from the RCS and periapical lesions. However, several bacteria seen in the histological sections were probably dead or were inactivated by the biomechanical preparation and calcium hydroxide-based intracanal dressing.

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Several studies have been conducted in the last decades aiming to obtain an anti-canies vaccine, however some studies have demonstrated cross reactivity between Streptococcus mutans surface antigens and the human cardiac tissue. In this work, the reactivity of five anti-Streptococcus mutans monoclonal antibodies (MoAb) (24A, 56G, G8, E8 and F6) was tested against oral streptococci, cardiac antigens and skeletal and cardiac myosins, aiming to evaluate the specificity of these MoAb. The hybrid producers of immunoglobulins of the IgG 2b class were cloned by limit dilution and expanded in vivo. MoAb were tested by ELISA. The hybrid 24A reacted with S. mutans CCT 1910, S. salivarius CCT 0365 and S. pyogenes T23. No reactivity difference was observed among the tested species. Cross reactivity with heart and cardiac myosin was not confirmed and only reaction with myosin of skeletal muscle was observed (p = 0.0381). The hybrid 56G reacted with all the tested microorganisms and there was statistically significant difference between S. mutans and S. pyogenes T23 (p < 0.001). This hybrid also reacted with myosin of skeletal muscle (p = 0.0095). C8, E8 and F6 presented low reactivity against oral streptococci strains and no reactivity against cardiac antigens. The data of this study showed that the 24A and 56G anti-S. mutans MoAb presented reactivity with S. pyogenes and S. salivarius, reinforcing the occurrence of common antigens between these species. The tested MoAb presented low cross-reactivity with myosin of skeletal muscle, but anti-heart activity could not be confirmed.

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We present a search for associated Higgs boson production in the process pp̄→WH→WWW*→l±νl′±ν′ +X in final states containing two like-sign isolated electrons or muons (e±e±, e±μ±, or μ±μ±). The search is based on D0 run II data samples corresponding to integrated luminosities of 360-380pb-1. No excess is observed over the predicted standard model background. We set 95% C.L. upper limits on σ(pp̄→WH) ×Br(H→WW*) between 3.2 and 2.8 pb for Higgs boson masses from 115 to 175 GeV. © 2006 The American Physical Society.

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The aim of the study was to evaluate production and determine the level of total soluble solids for cherry tomatoes, under protected cultivation carried out with different types of spacing and pruning. The experiment was performed according to a randomized block design in a 2×2 factorial scheme, with two types of spacing between plants and two types of pruning, and with five repetitions. The cultivar 'Sindy' (De Ruiter) was utilized. Each experimental parcel contained seven plants, and fruits were collected from the five central plants. The seedlings were produced in Styrofoam trays of 128 cells and transplanted at 33 days after planting using two types of spacing between plants (0.3 and 0.5 m) and 1 m spacing between rows. The plants were grown as single-or double-stem form and staked individually. The parameters evaluated were the number of fruit per plant, fresh weight of fruit and the level of total soluble solids expressed in °Brix. There was no evidence of significant interaction between the treatments. For fresh weight of fruit per plant, there was a significant effect when the plants were grown with a spacing of 1 × 0.5 m, with 4.12 kg per plant, compared to a production of 3.00 kg per plant with a spacing of 1 × 0.3 m. With regard to the number of fruit per plant, a significant difference was seen between the two types of spacing, where a spacing of 1 × 0.3 m yielded a lower number of fruit per plant (188.8), compared to that observed with a spacing of 1 × 0.5 m (238.1). With regard to the two types of pruning, there was a significant effect for only the number of fruit per plant, where the mean number of fruit was 188.4 with one stem and 238.4 with two stems. No significant difference was observed between the treatments for the level of total soluble solids. It is concluded that for the cultivar 'Sindy', under protected cultivation, production is better with a spacing of 0.5 m between plants and the use of two stems per plant.

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The aim of the work was to evaluate the performance of four cultivars of iceberg lettuce, in a greenhouse, with and without ground cover. The experimental design adopted was that of subdivided parcels, where parcels were provided with and without ground cover consisting of black polyethylene and the subparcels consisted of the cultivars. There were three repetitions per treatment and six central plants of each parcel were evaluated. Drip irrigation was utilized. The cultivars studied were: 'Laurel', 'AF-389', 'Mayara' and 'Tainá'. The seeds were planted in Styrofoam trays with 288 cells containing the substrate Plantmax Hortaliças® A. The trays were kept in a greenhouse until transplanting, 25 days after seeding. The parameters examined were: fresh weight of the aerial part per plant, longitudinal (DL) and transverse (DT) diameters of the head, height of the plant and mean number of leaves per plant. Only among the cultivars there were significant differences in transverse and longitudinal diameters of the head and height of the plant. No significant interactions were detected between ground cover and cultivars. With regard to longitudinal and transverse diameters, 'AF-839' (DL = 27.11 cm; DT = 24.53 cm) showed smaller diameters than those of 'Laurel' (DL = 31.13 cm; DT = 30.55 cm), but did not differ from the other cultivars. In regard to height of the plants, 'Laurel' (20.66 cm) had the greatest value and 'AF-839' (16.02 cm) the lowest. The cultivars did not differ with respect to mean number of leaves and fresh weight of the aerial part of the plant. It is concluded that there were no significant differences in the cultivation of the iceberg lettuce with and without ground cover. The cultivar 'Laurel' stood out with respect to longitudinal and transverse diameters and height of the plant, only differing from the 'AF-839' with regard to the diameters.

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The aim of this study was to evaluate the antimicrobial activity of different trademarks and compositions of gutta-percha points and calcium hydroxide pastes used in endodontic therapy. The evaluated material consisted of gutta-percha points containing calcium hydroxide (Roeko™), gutta-percha points containing chlorhexidine (Roeko™), two convencional gutta-percha points (Endo Points™ and Roeko™) and two calcium hydroxide pastes (Calen™ and Calen/PMCC™). Antimicrobial tests included five species of microorganisms: Escherichia coli (ATCC10538), Staphylococcus epidermidis (ATCC12228), Staphylococcus aureus (ATCC6538), Pseudomonas aeruginosa (ATCC27853), and Micrococcus luteus (ATCC9341). The Agar difusion method was employed. The plates were kept at room temperature for 2 h for prediffusion and then incubated at 37°C for 24 h. The triphenyltetrazolium chloride gel was added for optimization and the zones of inhibition were measured. Statistical evaluation was carried out using analysis of variance and Tukey Test. The obtained results showed that all microbial species used in the study were inhibited by the gutta-percha points containing chlorhexidine and by the calcium hydroxide pastes (Calen™ and Calen/ PMCC™), with similar results (p > 0.05). No antimicrobial activity was observed for the other groups. It was concluded that the gutta-percha points containing chlorhexidine presented antimicrobial activity, whereas the gutta-percha points containing calcium hydroxide did not.

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Uncaria tomentosa is considered a medicinal plant used over centuries by the peruvian population as an alternative treatment for several diseases. Many microorganisms usually inhabit the human oral cavity and under certain conditions can become etiologic agents of diseases. The aim of the present study was to evaluate the antimicrobial activity of different concentrations of Uncaria tomentosa on different strains of microorganisms isolated from the human oral cavity. Micropulverized Uncaria tomentosa was tested in vitro to determine the minimum inhibitory concentration (MIC) on selected microbial strains. The tested strains were oral clinical isolates of Streptococcus mutans, Staphylococcus spp., Candida albicans, Enterobacteriaceae and Pseudomonas aeruginosa. The tested concentrations of Uncaria tomentosa ranged from 0.25-5% in Müeller-Hinton agat. Three percent Uncaria tomentosa inhibited 8% of Enterobacteriaceae isolates, 52% of S. mutans and 96% of Staphylococcus spp. The tested concentrations did not present inhibitory effect on P. aeruginosa and C. albicans. It could be concluded that micropulverized Uncaria tomentosa presented antimicrobial activity on Enterobacteriaceae, S. mutans and Staphylococcus spp. isolates.

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The aim of this study was to evaluate the antimicrobial activity of different root-end filling materials - Sealer 26, Sealapex with zinc oxide, zinc oxide and eugenol, white and gray Portland cement, white and gray MTA-Angelus, and gray Pro Root MTA - against six different microorganism strains. The agar diffusion method was used. A base layer was made using Müller-Hinton agar (MH) and wells were formed by removing the agar. The materials were placed in the wells immediately after manipulation. The microorganisms used were: Micrococcus luteus (ATCC9341), Staphylococcus aureus (ATCC6538), Escherichia coli (ATCC10538), Pseudomonas aeruginosa (ATCC27853), Candida albicans (ATCC 10231), and Enterococcus faecalis (ATCC 10541). The plates were kept at room temperature for 2 h for prediffusion and then incubated at 37 degrees C for 24 h. Triphenyltetrazolium chloride 0.05% gel was added for optimization, and the zones of inhibition were measured. Data were subjected to the Kruskal-Wallis and Dunn tests at a 5% significance level. The results showed that all materials had antimicrobial activity against all the tested strains. Analysis of the efficacy of the materials against the microbial strains showed that Sealapex with zinc oxide, zinc oxide and eugenol and Sealer 26 created larger inhibition halos than the MTA-based and Portland cements (P < 0.05). On the basis of the methodology used, it may be concluded that all endodontic sealers, MTA-based and Portland cements evaluated in this study possess antimicrobial activity, particularly the endodontic sealers.

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The aim of this study was to evaluate the antimicrobial activity of different coffee solutions and their effects on the adherence of Streptococcus mutans to glass surface. Coffee solutions were prepared with three commercial products (Pilao, Mellita and Café do Ponto) by two different methods (simple and boiled) (n=15). A control group was also included in the study. For antimicrobial activity testing, tubes containing coffee solution and culture medium were inoculated with a suspension of S. mutans ATCC 35688 and incubated for 1 min 1h, 2h and 4h. Serial dilutions and plating on BHI agar were performed. S, mutans adherence to glass in presence of different coffee solutions was also tested. The number of adhered bacteria (CFU/mL) was determined by plating method. The results were statistically analyzed by ANOVA and Turkey's test. The tested coffee solutions did not reduce the number of colony forming units of S. mutans in relation to the control at all evaluation periods. All the solutions reduced significantly the adherence of S. mutans to the glass surface in relation to control. The tested coffee solutions did not present any antimicrobial effect on Streptococcus mutans, however, all the coffee solutions reduced significantly the adherence of S mutans to the glass surface.

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We present a study of eeγ and μμγ events using 1109 (1009) pb-1 of data in the electron (muon) channel, respectively. These data were collected with the DØ detector at the Fermilab Tevatron p over(p, ̄) collider at sqrt(s) = 1.96   TeV. Having observed 453 (515) candidates in the eeγ (μμγ) final state, we measure the Zγ production cross section for a photon with transverse energy ET > 7   GeV, separation between the photon and leptons Δ Rℓ γ > 0.7, and invariant mass of the di-lepton pair Mℓ ℓ > 30   GeV / c2, to be 4.96 ± 0.30 (stat . + syst .) ± 0.30 (lumi .)   pb, in agreement with the Standard Model prediction of 4.74 ± 0.22   pb. This is the most precise Zγ cross section measurement at a hadron collider. We set limits on anomalous trilinear Zγγ and ZZγ gauge boson couplings of - 0.085 < h30 γ < 0.084, - 0.0053 < h40 γ < 0.0054 and - 0.083 < h30 Z < 0.082, - 0.0053 < h40 Z < 0.0054 at the 95% C.L. for the form-factor scale Λ = 1.2   TeV.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The purpose of this study was to evaluate the residual antibacterial activity of several calcium hydroxide [Ca(OH) 2]-based pastes, placed in root canals of dogs' teeth with induced chronic periapical lesions. Root canals were instrumented with the ProFile rotary system and filled with 4 pastes: G1 (n=16): Ca(OH) 2 paste + anesthetic solution; G2 (n=20): Calen® paste + camphorated pmonochlorophenol (CMCP); G3 (n=18): Calen®; and G4 (n=18): Ca(OH) 2 paste + 2% chlorhexidine digluconate. After 21 days, the pastes were removed with size 60 K-files and placed on Petri plates with agar inoculated with Micrococcus luteus ATCC 9341. Pastes that were not placed into root canals served as control. After pre-diffusion, incubation and optimization, the inhibition zones of bacterial growth were measured and analyzed by Mann-Whitney U test at 5% significance level. All pastes showed residual antibacterial activity. The control samples had larger halos (p<0.05). The mean residual antibacterial activity halos in G1, G2, G3 and G4 were 7.6; 10.4; 17.7 and 21.4 mm, respectively. The zones of bacterial growth of G4 were significantly larger than those of G1 and G2 (p<0.05). In conclusion, regardless of the vehicle and antiseptic, all Ca(OH) 2-based pastes showed different degrees of measurable residual antibacterial activity. Furthermore, unlike CMCP, chlorhexidine increased significantly the antibacterial activity of Ca(OH) 2.

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This in vivo experimental study evaluated the efficacy of fluoride-releasing elastomers in the control of Streptococcus mutans levels in the oral cavity. Forty orthodontic patients were recruited and divided into two groups of 20. Fluoride-releasing elastomeric ligature ties (Fluor-I-Ties, Ortho Arch Co. Inc., USA) were used in the experimental group, and conventional elastomeric ligature ties (D. Morelli, Brazil), in the control group. Two initial samples of saliva were collected at a 14-day interval to determine the number of colony forming units (CFU) of Streptococcus mutans. Immediately after collecting the second sample, fluoride-releasing elastomeric ligature ties were placed in the patients of the experimental group, and conventional ligature ties, in the patients of the control group. Seven, 14 and 28 days after placement of the elastomeric ligature ties, saliva and plaque surrounding the orthodontic appliance were collected for microbiologic analysis. There were no significant differences in the number of Streptococcus mutans CFUs in saliva or plaque in the area surrounding the fluoride-releasing or conventional elastomeric ligature ties. Thus, fluoride-releasing elastomeric ligature ties should not be indicated to reduce the incidence of enamel decalcification in orthodontic patients. Since there was no significant reduction in S. mutans in saliva or plaque, other means of prevention against enamel decalcification should be indicated for these patients.

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The experiment was conducted in the experimental area belonging to the Section of Crop Production and Aromatic Medicinal Plants of the FCAV-UNESP, Jaboticabal Campus - Sao Paulo, Brazil. Tolerance to high temperature was studied in six determinate genotypes of tomato (Lycopersicon esculentum L.): Agrocica 8, Apex 1000, Botu-13, Calmech VFAS, Nemadoro and Jab-2, which were cultivated in a greenhouse at temperatures above 33oC for at least 2 h/day during blooming. The objectives of the study were to identify the genetic diversity of the genotypes studied and to determine their performance associated with tolerance to high temperature. Dissimilarity was determined by the generalized Mahalanobis distance. Delineation groups were optimized with the Tocher technique. A random block design was utilized with six treatments and with three replications. Two similarity groups were identified: 1 - Apex 1000, Botu-13, Calmech VFAS, Jab-2, Nemadoro and 2 - Agrocica 8. Crossing of genotypes within one group has no advantage because little genetic divergence and no heterotic response would be expected. However, the crossing of genotypes between groups is suggested. Knowledge of these groups will be important for efficiency future breeding efforts.