Three-year Randomized Prospective Clinical Trial of Class II Restorations Using Flowable Bulk-fill Resin Composites.

OBJECTIVES: This randomized, prospective, and split-mouth study aimed to evaluate flowable bulk-fill resin composites in class II restorations and to compare with a conventional layering technique after a 3-year follow-up. METHODS AND MATERIALS: Fifty-three subjects received three class II restorations according to the restorative systems: conventional microhybrid resin composite (PA, Peak Universal + Amelogen Plus, Ultradent), flowable bulk-fill and nanoparticulate resin composites (ABF, Adper Single Bond 2 + Filtek Bulk Fill Flow + Filtek Z350XT, 3M Oral Care), and flowable bulk-fill and microhybrid resin composites (XST, XP Bond + SDR + TPH3, Dentsply). The clinical performance and interproximal contacts were evaluated. Statistical analyses were performed using the equality test of two proportions, Logistic regression analysis, Friedman, Wilcoxon, Kruskal-Wallis, and Mann-Whitney tests (a=0.05). RESULTS: Forty-seven patients were evaluated at 3 years. XST bulk-fill restorative system presented higher marginal discoloration than PA, and the opposite occurred for surface staining. All restorative systems resulted in decreased interproximal contacts, occurring early for XST. CONCLUSIONS: Although the restorative system using incremental technique presented better performance for marginal discoloration, one of the restorative systems that used flowable bulk-fill resin composite (XST) showed the lowest surface staining. All restorative systems had decreased proximal contact over time.

Nanoparticles enhance the ability of human neutrophils to exert phagocytosis by a Syk-dependent mechanism.

BACKGROUND: Some reports indicate that NPs are ingested by cells via different mechanisms, including phagocytosis. In contrast, the direct role of NPs on the phagocytic process is not well documented. The aim of this study was to determine if titanium dioxide (TiO(2)), zinc oxide (ZnO) and cerium dioxide (CeO(2)) NPs, could alter the ability of neutrophils to exert phagocytosis. METHODS: Freshly isolated human neutrophils were incubated with NPs and their ability to phagocytose opsonized sheep red blood cells (SRBCs) or fluorescent latex beads (LBs) was assessed by optical and fluorescence microscopy, respectively. Syk activation was assessed by western blot experiments and a pharmacological approach with piceatannol, a Syk inhibitor, was used to determine its role in NPs-induced neutrophils. The cytokine granulocyte macrophage-colony stimulating factor (GM-CSF) was used as a positive control. RESULTS: All tested NPs enhanced the ability of neutrophil to phagocytose SRBCs and LBs. Syk was activated in NPs-induced neutrophils as evidenced by its increased tyrosine phosphorylation level vs controls and the ability of NPs-induced phagocytosis was reversed by piceatannol. CONCLUSIONS: We found that the tested NPs enhanced phagocytosis, although at different degree, and this occurred by a Syk-dependent mechanism. GENERAL SIGNIFICANCE: This is the first study demonstrating that NPs, by themselves, can directly enhance FcR-mediated (opsonized SRBCs) and complement-mediated (LBs) phagocytosis. Moreover, as part of their mode of action, we determined that NPs can act similarly to GM-CSF leading to Syk activation involved in phagocytosis. This has to be taken under consideration for future nanobiology and nanomedicine studies.

Evidence that polyhydroxylated C60 fullerenes (fullerenols) amplify the effect of lipopolysaccharides to induce rapid leukocyte infiltration in vivo.

Fullerenols C60(OH) have therapeutic potential, but there is debate regarding their toxicity. Here, we tested the hypothesis that C60(OH)n possesses a pro-inflammatory effect in vivo. Kinetic and dose-dependent experiments performed with the murine air pouch model of acute inflammation revealed that, unlike TiO2 used as a positive control in this model, C60(OH)n NPs were not pro-inflammatory in CD-1, C57BL/6, and BALB/c mice. However, after 3 h of treatment, C60(OH)n NPs were found to amplify the effect of lipopolysaccharides (LPS) causing a rapid leukocyte influx in which the major cells observed are neutrophils. The use of an antibody array assay to detect different analytes simultaneously indicates that the amplification effect is, at least partially, explained by an increased local production of several cytokines/chemokines in the exudates, including the pro-inflammatory cytokine IL-6. Using an ELISA to quantify the amount of IL-6 produced into air pouch exudates, we demonstrated that C60(OH)n increases the LPS-induced local production of this cytokine. Therefore, although C60(OH)n NPs alone do not exert proinflammatory activity under certain conditions, they can act in concert with other agents to cause inflammation, a situation that is likely to occur in vivo.

Titanium dioxide (TiO2) nanoparticles induce neutrophil influx and local production of several pro-inflammatory mediators in vivo.

We have recently described the in vitro effects of titanium dioxide (TiO(2)) nanoparticles (NPs) in human neutrophils. The objective of the present study was to determine if TiO(2) NPs induced leukocyte infiltration in the in vivo murine air pouch model of acute inflammation and, if so, to identify which of the main cell populations were attracted. TiO(2) NPs induced leukocyte influx after 3-9h of treatment, since the number of leukocytes attracted significantly increased when compared to controls. Neutrophils are the most abundant leukocytes attracted by TiO(2) representing more than ~80% of cells, with the rest being mononuclear cells. Using an antibody array technique to detect 40 different analytes, we observed that TiO(2) increased the local production of several analytes in the exudates, including diverse chemokines. Using an ELISA assay, we found that the concentration of TiO(2)-induced MIP-1ß was significantly increased vs controls, corroborating the antibody array results.

Avaliação da atividade antimicrobiana in vitro do extrato de Tabernaemontana catharinensis A. DC / Evaluation of in vitro antimicrobial activity of Tabernaemontana catharinensis A. DC. extract

Diversas espécies de Tabernaemontana têm sido estudadas devido a diversidade de alcalóides com atividade farmacológica. O objetivo desse trabalho foi avaliar a capacidade antimicrobiana in vitro do extrato das cascas do caule de Tabernaemontana catharinensis A. DC.em cepas de Staphylococcus aureus e Pseudomonas aeruginosa, microrganismos causadores de diversas infecções. Os testes de susceptibilidade bacteriana foram realizados usando o método de Kirby Bauer, consistindo na difusão em disco do antibiótico em meio de cultivo Mueller Hinton. Os testes de inibição foram realizados com soluções do extrato bruto seco de T. catharinensis dissolvido em etanol 70 por cento (v/v) na concentração 1,0 mg mL-1, que aplicada nos discos de área 20 mm², apresentaram concentração de 0,005 mg mm-2. Como controle negativo, realizou-se ensaios com placas contendo P. aeruginosa, e discos com etanol 70 por cento (v/v), e como controle positivo, discos com os antibióticos ceftriaxona sódica (0,25 mg mm-2 de área do disco), tetraciclina (0,005 mg mm-2) e cefalexina (0,005 mg mm-2). A solução do extrato na concentração de 0,005 mg mm-2 inibiu o Staphylococcus aureus, com diâmetro médio do halo de 0,6 cm. O halo de inibição para o Pseudomonas aeruginosa foi em média 1,2 cm. A tetraciclina, a cefalexina, e o controle negativo (etanol 70 por cento v/v) não demonstraram ação antimicrobiana. O halo de inibição usando ceftriaxona foi em média 2,2 cm para P. aeruginosa e 1,0 cm para Staphylococcus aureus.

Several Tabernaemontana species have been studied due to their several alkaloids with pharmacological activity. The aim of this work was to evaluate the in vitro antimicrobial action of the extract from stem barks of Tabernaemontana catharinensis A. DC. against strains of Staphylococcus aureus and Pseudomonas aeruginosa, microorganisms that cause several infections. Bacterial susceptibility tests were performed by the Kirby-Bauer method, consisting in antibiotic disk diffusion in Mueller Hinton medium. Inhibition tests were performed with solutions of T. catharinensis dry crude extract dissolved in ethanol 70 percent (v/v) at 1.0 mg mL-1, which became 0.005 mg mm-2 when applied to 20 mm² disks. As negative control, assays were carried out in plates containing P. aeruginosa and disks with ethanol 70 percent (v/v). Positive control consisted of disks containing the antibiotics ceftriaxone sodium (0.25 mg mm-2 disk area), tetracycline (0.005 mg mm-2) and cephalexin (0.005 mg mm-2). Extract solution at 0.005 mg mm-2 inhibited Staphylococcus aureus, with 0.6cm halo mean diameter. The inhibition halo for Pseudomonas aeruginosa was on average 1.2 cm. Tetracycline, cephalexin and negative control (ethanol 70 percent v/v) did not show antimicrobial action, whereas ceftriaxone sodium resulted in 2.2 and 1.0cm mean inhibition halo diameters for P. aeruginosa and Staphylococcus aureus, respectively.

Activation of human neutrophils by titanium dioxide (TiO2) nanoparticles.

This paper describes the in vitro effects of titanium dioxide (TiO(2)) nanoparticles (NPs) upon human neutrophils. Kinetic experiments revealed no cell necrosis after 24h of treatment with TiO(2) (0-100 microg/ml). In contrast, TiO(2)-induced change in cellular morphology in a concentration-dependent manner in neutrophils over time, indicating its potential to activate these cells. To further support this, we demonstrated that TiO(2) markedly and rapidly induced tyrosine phosphorylation events, including phosphorylation of two key enzymes, p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinases-1/2 (Erk-1/2). We also determined the effects of TiO(2) on two neutrophil functions requiring a longer exposure period between NPs and cells: apoptosis and cytokine production. Interestingly, at concentrations >or=20 microg/ml, TiO(2) inhibited neutrophil apoptosis in a concentration-dependent manner after 24h of treatment. Supernatants from TiO(2)-induced neutrophils were harvested after 24h and tested for the presence of 36 different analytes (cytokines, chemokines) using an antibody array assay. TiO(2) treatment increased production of 13 (36%) analytes, including IL-8, which exhibited the greatest increase ( approximately 16 x control cell levels). The increased production of IL-8 was confirmed by ELISA. We conclude that TiO(2) exerts important neutrophil agonistic properties in vitro.

11-Ketotestosterone inhibits the alternative mating tactic in sneaker males of the peacock blenny, Salaria pavo.

In the peacock blenny, Salaria pavo, a species with courtship sex-role reversal, smaller, younger males mimic the courtship behavior and the nuptial coloration of females in order to get access to nests during spawning and to parasitize egg fertilization from nest-holder males. Later in their life, sneakers transform both morphologically and behaviorally into nest-holder males. In the present paper we investigate the activational role of 11-ketotestosterone (KT), the most potent androgen in most teleost species, to promote the switch between tactics in sneaker males of S. pavo. Sneakers were implanted either with KT or with control (i.e. castor oil) silastic implants. A week after implantation they were subjected to a set of behavioral tests and morphometric measurements. KT treatment promoted the differentiation of secondary sex characters, such as the anal glands, and inhibited the expression of female courtship behavior. KT-treated sneakers also showed a trend toward less frequent display of female nuptial coloration. There was no effect of KT treatment on the expression of typical nest-holder male behavior. Finally, there was no effect of KT treatment on the number or soma size of arginine vasotocin neurons in the preoptic area, which are often associated with the expression of vertebrate sexual behavior. Thus, KT seems to play a key role in mating tactic switching by inhibiting the expression of female courtship behavior and by promoting the development of male displaying traits (e.g. anal glands). The lack of a KT effect on behavior typical of nest-holding males and vasotocinergic preoptic neurons suggests that a longer time frame or other endocrine/social signals are needed for the initiation of these traits in males that are switching tactics.