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OBJECTIVES: The present study evaluated the influence of a flowable resin layer on bond strength between resin cement and a universal adhesive applied using an immediate dentin sealing (IDS) technique. METHODS AND MATERIALS: Coronary portions of bovine teeth were randomly divided into six groups (n=15). In the IDS.U group, the exposed dentin was immediately sealed with the Single Bond Universal adhesive (3M ESPE) following the self-etching protocol. In the IDS.UF group, a layer of Filtek Z350 (3M ESPE) flow resin was applied over the universal adhesive. In the DDS (control) group, the dentin was kept "fresh" and delayed dentin sealing was performed. After 24 hours in distilled water at 37°C, dentin surfaces were treated with pumice, phosphoric acid, and the application of the universal adhesive in the IDS.U and IDS. UF groups. The DDS group was treated with pumice and the universal adhesive was applied. The samples received cylinders of resin cement Rely X Ultimate (3M ESPE) made with the aid of starch tubes of 0.96 mm in diameter and 2 mm in length. They were submitted to the microshear bond strength test (µSBS) at 0.5 mm/min, after 24 hours (T1) and 3 months (T2). The fracture areas were evaluated qualitatively using a DSM 300 microscope (KOZO) with 45× magnification and classified as: adhesive, cohesive in cement, cohesive in dentin, or mixed. Samples were analyzed by scanning electron microscopy (SEM). The data were compared statistically between groups using the Kruskal-Wallis test, and intra-groups using the Mann-Whitney test (α=0.05). RESULTS: There were no significant differences between groups for the bond strength values (p>0.05). The IDS.UF group showed higher values at 3 months, when compared to the values of 24 hours (p<0.001). All groups showed a predominance of adhesive fracture (86.7% to 100%). SEM showed dentinal tubules exposed in the IDS.U and DDS groups; in the IDS.UF group, the tubules were completely sealed. CONCLUSIONS: The flow resin can be used on the adhesive when using the IDS technique because it increased the bond strength values after 3 months and promoted effective sealing of the dentinal tubules.

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We studied the mechanisms involved in the human corpora cavernosa (HCC) relaxation induced by a new metal-based nitric oxide (NO) donor, the ruthenium complex cis-[Ru(bpy)2Imn(NO)](+3) (FOR0811). FOR0811 produced relaxation in phenylephrine (PE)-precontracted HCC with a maximal response that achieved 112.9 ± 10.6%. There was no difference between the maximal relaxation induced by FOR0811 when compared with sodium nitroprusside (SNP) (106.8 ± 7.3%), BAY41-2272 (107.6 ± 4.1%) or vardenafil (103.4 ± 3.8%), however, FOR0811 was less potent than SNP and vardenafil. L-N(G)-nitroarginine methyl ester (L-NAME), a NO synthase inhibitor, had no effect in the concentration-response curve elicited by FOR0811. 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), a heme-site inhibitor of soluble guanylyl cyclase (sGC) was able to either block or reverse the relaxation induced by FOR0811. On the other hand, the relaxation induced by FOR0811 was not affected by glibenclamide, a blocker of ATP-sensitive potassium channels. FOR0811 (10 µM) was able to increase cyclic guanosine monophosphate (cGMP) levels in corpora cavernosa strips. FOR0811 completely relaxes HCC by a sGC-cGMP-dependent mechanism and can be a lead compound in the development of new stable NO donors.

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When ozone is used during caries treatment, bond strength can be compromised by the release of oxygen. The use of antioxidant agents neutralizes the free oxygen. The aim of this study was to evaluate the effects of ozone and sodium ascorbate on resin-dentin microtensile bond strength (µTBS). Forty human third molars were divided into four groups: Group 1, not treated with ozone; Group 2, ozone application followed by acid etching; Group 3, acid etching followed by ozone application; and Group 4, ozone and application of sodium ascorbate. Bonded beams (1.0 mm(2)) were tested under tension (0.5 mm min(-1)). The µTBS values were analyzed using one-way analysis of variance (ANOVA) and the Tukey test (p=0.05). All beams that fractured were analyzed under stereomicroscopy (40×). Group 1 had significantly higher µTBS values than Group 2 or 3. The µTBS values of Groups 1 and 4 were similar and higher than those of Group 2. The use of ozone in Group 2 resulted in lower values of µTBS in all conditions evaluated. The predominant failure mode was adhesive. The application of ozone decreased the µTBS of the dentin-composite resin interface. These values were reversed when compared with Groups 1 and 2 when sodium ascorbate was used.

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Um dos equipamentos termoterapêuticos utilizados para a produção do calor é o que utiliza princípios de ultra-som (US) produzindo calor profundo pela propagação das suas ondas mecânicas, que são essencialmente as mesmas das ondas sonoras, mas com uma frequência mais alta. O US é produzido por uma corrente alternada que flui por um cristal piezoelétrico, alojado em um transdutor. Os efeitos do US dependem de muitos fatores físicos e biológicos, tais como a iontensidade, o tempo de exposição, a estrutura espacial e temporal do campo ultra-sônico e o estado fisiológico do local a ser tratado. Este grande número de variáveis complica a compreensão exata do seu mecanismo de ação na interação com os tecidos biológicos. Os efeitos do US vem sendo investigados e descritos de maneira empírica através dos tempos e as opinio~es sobre as dosagens utilizadas para o tratamento diferem significativamente, existindo poucas evidências dos seus efeitos clínicos. Sendo assim, este trabalho tem como objetivo apontar, mediante uma revisão bibliográfica, se existem parâmetros físicos e biológicos para determinaçãoi das doses de US, quando utilizado para fins terapêuticos

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The purpose of this study was to evaluate the clinical performance of two "packable" posterior composites: Prodigy Condensable/Optibond Solo-Kerr (PC-OS) and Definite/Etch & Prime-Degussa (D-EP). Thirty-six patients participated in this study. A total of 78 restorations (40 with D-EP and 38 with PC-OS) were made. Each patient received at least two restorations (one of each studied material). The materials were handled according to the manufacturer's instructions. The occlusal adjustments were made at the placement visit. The restorations were finished and polished after 1 week. They were evaluated at baseline, and after 1 year and 2 years by two independent evaluators using the USPHS criteria. Colored slides were made of all the restorations. After 2 years, 34 patients and 74 restorations (38 with D-EP and 36 with PC-OS) were available for evaluation. A total of 50% of PC-OS restorations received A criterion and 50% received B criterion (2.8% color, 11.1% marginal staining, 27.8% superficial staining, 2.8% anatomic form and 5.6% marginal adaptation). For D-EP, 60.5% of restorations received A criterion and 39.5% received B criterion (2.6% color, 5.3% marginal staining, 10.5% superficial staining, 7.9% anatomic form and 13.2% marginal adaptation). The C criterion was observed only for marginal adaptation with D-EP (2 restorations-5.3%). The obtained data were tabulated and statistically analyzed using the Fisher, Chi-square and McNemar tests. After 2 years, PC-OS showed a significant increase in superficial and marginal staining. For D-EP the marginal adaptation and superficial staining became significantly worse than baseline.

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BACKGROUND: Helicobacter pylori eradication in family members of gastric cancer patients is now widely accepted, although problems related to costs and compliance persist. AIM: To compare the efficacy, tolerability and long-term re-infection rates of two once-daily regimens for the eradication of H. pylori in family members of gastric cancer patients. METHODS: 106 first-degree family members of gastric cancer patients were recruited and submitted to the 13C-urea breath test (UBT) to detect H. pylori. If positive, they were randomly allocated to receive a combination of lanzoprazole 30 mg, clarithromycin OD (extended-release formulation) 500 mg and furazolidone 400 mg, once daily, in the morning, for 7 days (Group A) or the same regimen with only 200 mg furazolidone (Group B). Eradication was confirmed by urea breath test performed 6 weeks after treatment. 13C-urea breath test was repeated at 944 (784-1258) days after treatment in successfully treated participants to look for re-infection. RESULTS: Twenty-five participants were H. pylori negative and two H. pylori-positive individuals refused to sign the informed consent and were excluded. Therefore, 79 participants were studied. Forty participants were allocated to Group A and 39 to Group B. All participants completed treatment. Adverse effects, mostly mild, were observed in 18% of Group A and 18% of Group B (N.S.). The intention-to-treat eradication rate was 87.5% in Group A and 61.5% in Group B (P = 0.006). The mean annual re-infection rate was 3%. CONCLUSIONS: The combination of lanzoprazole 30 mg, one tablet of clarithromycin OD (extended release formulation) 500 mg and furazolidone 400 mg, once daily for 7 days, constitutes an inexpensive, safe and effective alternative for anti-H. pylori therapy in family members of gastric cancer patients.

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The purpose of this study was to evaluate the clinical performance of two "packable" posterior composites: Prodigy Condensable (P) (Kerr) and Definite (D) (Degussa). Thirty-six patients participated in the study. A total of 78 restorations were made, 40 with D and 38 with P. Each patient received at least two restorations, one of each studied material. The materials were handled according to the manufacturer's instructions. The restorations were finished and polished after 1 week. They were evaluated at baseline and after 1 year by two independent evaluators using the United States Public Health Service (USPHS) criteria. Colored slides were made of all the restorations. After 1 year, 35 patients and 76 restorations (39 with D and 37 with P) were available for evaluation. All restorations received A criteria except the following ones, which received B criteria: color P (one restoration) and D (one restoration), marginal staining P (three restorations) and D (two restorations), surface staining P (nine restorations) and D (three restorations), anatomic form P (one restoration) and D (three restorations), and marginal adaptation P (one restoration) and D (eight restorations). The obtained data were tabulated and statistically analyzed using the Fisher and McNemar tests. After 1 year, P showed a significant increase in superficial staining. For D, the marginal adaptation became significantly worse than baseline and P. The studied materials can be considered acceptable during this evaluation period. Further evaluations are necessary for a better clinical performance analysis.

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The influence of different, nitric oxide-containing ruthenium complexes on the evoked potentials recorded from the CA1 region of the mouse hippocampus in vitro has been investigated. Of the compounds tested, only trans-[(NO)(P(OEt)3)(NH3)4Ru](PF6)3 (1-2.5 mM) exerted a strong facilitatory action on the population spike, the EPSP, and the spontaneous activity. Its activity probably depends upon its ability to release NO following reduction. The phosphito ligand is important both in terms of adjusting the reduction potential of the complex to be biologically accessible and in labilizing the coordinated NO. The effects of this compound could not be reversed by perfusion. Scavenging NO in slices preincubated with oxyhemoglobin prior to the addition of this compound eliminated its neurophysiological effects. The control molecules trans-[(P(OEt)3)2(NH3)4Ru](PF6)2, trans-[(H2O)(P(OEt)3) (NH3)4Ru](PF6)3, and [(NO)(NH3)5Ru]Cl3, which are structurally similar, but unable to generate NO, were ineffective. NaNO2 suppressed neuronal firing. Attempts to induce Long-Term Potentiation (LTP) at the time of maximal effect of trans-[(NO)(P(OEt)3)(NH3)4Ru](PF6)3 were unsuccessful, suggesting that the mechanism of amplification induced by trans-[(NO)(P(OEt)3)(NH3)4Ru](PF6)3 and LTP may share common pathways.

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Background: There is not yet consensus on the most effective treatment for the helicobacter pylori infection, particularly in most developing countries. Azithromycin is a new macrolide and relatively novel agent for H. pylori eradication with an in vitro MIC90 lower than 1 mg/ml.Secnidazole, a nitromidazole that causes fewer side effects than metronidazole, was recenty reported to be used, for the firt time, in the treatment of H. pylori infection. Aim: To evaluate, in a prospective, randomized, single-center study, the association of twodifferent doses of omeprazole, azithromycin and secnidazole in H. pylori eradication. Patients and methods: After informed consent, 55 patients (36m,19F) with duodenal ulcer associated with H. pylori infection were randomized to receive omeprazole 20mg uid (Group A) or 20mg bid (Group B) for sevem days plus azithromycin 500mg uid for six days and secnidazole 2,000mg uid in the first, fourth and seventh day. The H. pylori status was assessed before and 60-90 days posttreatment using urease test, histology and 13C-urea breath test. Statistical analysis was performed by X² test. Results: The two groups had similar demographic characteristics. Fifty-five patients (36M, 19F) were enrolled. Six patients did not show-up for the second visit posttreatment. So, of the 49 evaluable patients, 25por cento (6/24) in Group A and 44por cento(11/25) in Group B wereeradicated, in a per protocol (PP) analysis. Intetion-to-treat (ITT) eradication rates were 21,4por cento (6/28) in Group A and 40.7por cento (11/27) im Group B. The differences betweem ITT and PP analysis from the two groups were not statistically significant. Conclusions: This study shows a very low eradication rate with the two regimens comprising of omeprazole, azithromycin and secnidazole and therefore, should not be recommended for thetreatment of H. pylori infection

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The synthesis of trans-[RuCl(NO)(cyclam)]2+ (cyclam = 1,4,8,11-tetraazacyclotetradecane) can be accomplished by either the addition of cyclam to K2[RuCl5NO] or by the addition of NO to trans-[RuCl(CF3SO3)(cyclam)](CF3-SO3). Crystals of trans-[RuCl(NO)(cyclam)](ClO4)2 form in the monoclinic space group P2(1)/c, with unit cell parameters of a = 7.66500(2) A, b = 24.7244(1) A, c = 16.2871(2) A, beta = 95.2550(10) degrees, and Z = 4. One of the two independent molecules in the unit cell lies disordered on a center of symmetry. For the ion in the general position, the Ru-N and N-O bond distances and the [Ru-N-O]3+ bond angle are 1.747(4) A, 1.128(5) A, 178.0(4) degrees, respectively. In both ions, cyclam adopts the (R,R,S,S) configuration, which is also consistent with 2D COSY 1H NMR studies in aqueous solution. Reduction (E degree = -0.1 V) results in the rapid loss of Cl- by first-order kinetics with k = 1.5 s-1 and the slower loss of NO (k = 6.10 x 10(-4) s-1, delta H++ = 15.3 kcal mol-1, delta S++ = -21.8 cal mol-1 K-1). The slow release of NO following reduction causes trans-[RuCl(NO)(cyclam)]2+ to be a promising controlled-release NO prodrug for vasodilation and other purposes. Unlike the related complex trans-[Ru(NO)(NH3)4(P(OEt)3)](PF6)2, trans-[RuCl(NO)(cyclam)]Cl2 is inactive in modulating evoked potentials recorded from mice hippocampal slices probably because of the slower dissociation of NO following reduction.

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