Effect of collagen matrix saturation on the surface free energy of dentin using different agents

The surface free energy of conditioned-dentin is one of the factors that interfere with monomeric infiltration of the interfibrillar spaces. Saturation of the tooth matrix with different substances may modulate this energy and, consequently, the wettability of the dentin. To evaluate the influence of different substances used to saturate conditioned-dentin on surface free energy (SFE) of this substrate. Dentin blocks (4 × 7 × 1 mm, n = 6/ group), obtained from the roots of bovine incisors, were etched using phosphoric acid for 15 seconds, rinsed and gently dried. The surfaces were treated for 60 seconds with: ultra-purified water (H20-control); ethanol (EtOH), acetone (ACT), chlorhexidine (CHX), ethylenediaminetetraacetic acid (EDTA); or sodium hypochlorite (NaOCl). The tooth surfaces were once again dried with absorbent paper and prepared for SFE evaluation using three standards: water, formamide and bromonaphthalene. Analysis of variance (ANOVA) and Dunnet's tests (a = 0.05) were applied to the data. Ethylenediaminetetraacetic acid was the only substance that caused a change to the contact angle for the standards water and formamide, while only EtOH influenced the angles formed between formamide and the dentin surface. None of the substances exerted a significant effect for bromonaphtha-lene. In comparison to the control, only EDTA and NaOCl altered both polar components of the SFE. Total SFE was increased by saturation of the collagen matrix by EDTA and reduced when NaOCl was used. Saturation of the collagen matrix by EDTA and EtOH changed the surface free energy of the dentin. In addition, the use of NaOCl negatively interfered with the properties evaluated. The increase of surface free energy and wettability of the dentin surface would allow higher penetration of the the adhesive system, which would be of importance to the clinical success of resin-dentin union.

Anti-dementia medications: current prescriptions in clinical practice and new agents in progress

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

Tick-borne agents in domesticated and stray cats from the city of Campo Grande, state of Mato Grosso do Sul, midwestern Brazil

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

Vanadium complexes with hydrazone or thiosemicarbazone ligands as potential anti-mycobacterium tuberculosis agents

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Toxic heritage: maternal transfer of pyrethroid insecticides and sunscreen agents in dolphins from Brazil

Pyrethroids (PYR) and UV filters (UVF) were investigated in tissues of paired mother-fetus dolphins from Brazilian coast in order to investigate the possibility of maternal transfer of these emerging contaminants. Comparison of PYR and UVF concentrations in maternal and fetal blubber revealed Franciscana transferred efficiently both contaminants to fetuses (F/M > 1) and Guiana dolphin transferred efficiently PYR to fetuses (F/M > 1) different than UVF (F/M < 1). PYR and UVF concentrations in fetuses were the highest-ever reported in biota (up to 6640 and 11,530 ng/g lw, respectively). Muscle was the organ with the highest PYR and UVF concentrations (p < 0.001), suggesting that these two classes of emerging contaminants may have more affinity for proteins than for lipids. The high PYR and UVF concentrations found in fetuses demonstrate these compounds are efficiently transferred through placenta. This study is the first to report maternal transfer of pyrethroids and UV filters in marine mammals.

Brazilian community health agents and qualitative primary healthcare information

The aim of this study was to explore female community health agents’ views about the value of recording qualitative information on contextual health issues they observe during home visits, data that are not officially required to be documented for the Brazilian System of Primary Healthcare Information. Background: The study was conducted in community primary healthcare centres located in the cities of Araçatuba and Coroados (state of São Paulo) and Rio de Janeiro (state of Rio de Janeiro), Brazil. Methods: The design was a qualitative, exploratory study. The purposeful sampling criteria were being female, with a minimum of three years of continuous service in the same location. Data collection with 62 participants was conducted via 11 focus groups (in 2007 and 2008). Audio files were transcribed and submitted to the method of thematic analysis. Four themes guided the analysis: working with qualitative information and undocumented observation; reflecting on qualitative information; integrating/analysing quantitative and qualitative information; and information-sharing with agents and family health teams. In 2010, 25 community health agents verified the final interpretation of the findings. Findings: Participants valued the recording of qualitative, contextual information to expand understanding of primary healthcare issues and as an indicator of clients’ improved health behaviour and health literacy. While participants initiated the recording of additional health information, they generally did not inform the family health team about these findings. They perceived that team members devalued this type of information by considering it a reflection of the clientele’s social conditions or problems beyond the scope of medical concerns. Documentation of qualitative evidence can account for the effectiveness of health education in two ways: by improving preventative care, and by amplifying the voices of underprivileged clients who live in poverty to ensure the most appropriate and best quality primary healthcare for them.

Microhardness of luting agents used for fiber post cementation submitted to thermo cycling

Aims and Objectives: The aim of this study was to analyze the microhardness of three resin cements used in cementing glass fiber posts in bovine incisor. The microhardness was analyzed in cervical, middle and apical thirds before and after thermocycling process. Materials and Methods: Bovine teeth were instrumented and divided into 3 groups composed of 10 teeth each. Then, the teeth were sectioned and obturated and had their canals prepared at a depth of 12mm. Once proceeded the desobturation, the roots and glass fiber posts were prepared for adhesive cementation. After cementation, the microhardness reading was carried out. After initial reading, the samples were placed in a thermocycler and subjected to 2,000 cycles and a new microhardness reading. The data collected were subjected to analysis of variance (ANOVA) and Turkey’s test. Results: It was observed a statistical difference among the microhardness of resin cements. However, the statistical difference of microhardness before and after thermocycling appeared only in group U-200. Conclusion: Thermocycling reduced microhardness values in all cements evaluated in this study. The autopolymerizing cement Multilink presented the most stable microhardness mean values after thermocycling in the coronal, middle and apical thirds.

Effect of light-activation on the antibacterial activity of dentin bonding agents

Aim: This study evaluated the effect of light-activation on the antibacterial activity of dentin bonding systems. Methods: Inocula of Streptococcus mutans and Lactobacillus casei cultures were spread on the surface of BHI agar and the materials were applied and subjected or not to light-activation. Zones of bacterial growth inhibition around the discs were measured. Results: Excite, Single Bond and the bond of Clearfil SE Bond (SE) and Clearfil Protect Bond (CP) did not show any antibacterial activity. The strongest inhibitory activity was observed for the primers of CP and Prompt (PR) against S. mutans and the primers of SE and PB against L. casei. Conclusion: Light-activation significantly reduced or suppressed the antibacterial activity of the initially active uncured dentin bonding systems.

Endophytic microorganisms isolated from coffee leaves, roots and branches as plant growth promoters and biocontrol agents of coffee leaf rust

Suppression of plant diseases and growth promotion due to the action of endophytic microorganisms has been demonstrated in several pathosystems. Experiments under controlled conditions involving 234 endophytic bacteria and fungi isolated from coffee leaves, roots and branches were conducted with the objective of evaluating the germination inhibition of Hemileia vastatrix urediniospores, the control of coffee leaf rust development in tests with leaf discs and on plastic bags seedling, and to promote growth of coffee seedlings. None of the fungal isolates induced plant growth or reduced disease severity. The bacterial isolates (identified by the fatty acids profile analysis) 85G (Escherichia fergusonii), 161G, 163G, 160G, 150G (Acinetobacter calcoaceticus) and 109G (Salmonella enterica) increased plant growth, the maximum being induced by 85G. This isolate produced in vitro phosphatase and indol acetic acid. In assay to control rust on coffee leaf disc, nine bacterial isolates, 64R, 137G, 3F (Brevibacillus choshinensis), 14F (Salmonella enterica), 36F (Pectobacterium carotovorum), 109G (Bacillus megaterium), 115G (Microbacterium testaceum), 116G and 119G (Cedecea davisae) significantly reduced disease severity, when applied 72 or 24h before challenging with the pathogen. In seedling tests most disease severity reduction was achieved by the isolates 109G and 119G. There was no correspondence between the organisms that promoted seedling growth and those that reduced rust severity on seedlings or leaf discs.

Cocaine effects on mouse incentive-learning and human addiction are linked to alpha 2 subunit-containing GABA(A) receptors

Because GABA(A) receptors containing alpha 2 subunits are highly represented in areas of the brain, such as nucleus accumbens (NAcc), frontal cortex, and amygdala, regions intimately involved in signaling motivation and reward, we hypothesized that manipulations of this receptor subtype would influence processing of rewards. Voltage-clamp recordings from NAcc medium spiny neurons of mice with alpha 2 gene deletion showed reduced synaptic GABA(A) receptor-mediated responses. Behaviorally, the deletion abolished cocaine`s ability to potentiate behaviors conditioned to rewards (conditioned reinforcement), and to support behavioral sensitization. In mice with a point mutation in the benzodiazepine binding pocket of alpha 2-GABA(A) receptors (alpha 2H101R), GABAergic neurotransmission in medium spiny neurons was identical to that of WT (i.e., the mutation was silent), but importantly, receptor function was now facilitated by the atypical benzodiazepine Ro 15-4513 (ethyl 8-amido-5,6-dihydro-5-methyl-6-oxo-4H-imidazo [1,5-a] [1,4] benzodiazepine-3-carboxylate). In alpha 2H101R, but not WT mice, Ro 15-4513 administered directly into the NAcc-stimulated locomotor activity, and when given systemically and repeatedly, induced behavioral sensitization. These data indicate that activation of alpha 2-GABA(A) receptors (most likely in NAcc) is both necessary and sufficient for behavioral sensitization. Consistent with a role of these receptors in addiction, we found specific markers and haplotypes of the GABRA2 gene to be associated with human cocaine addiction.

Treatment of Nuclear-Donor Cells or Cloned Zygotes with Chromatin-Modifying Agents Increases Histone Acetylation But Does Not Improve Full-Term Development of Cloned Cattle

Although somatic cell nuclear transfer (SCNT) is a promising tool, its potential use is hampered by the high mortality rates during the development to term of cloned offspring. Abnormal epigenetic reprogramming of donor nuclei after SCNT is thought to be the main cause of this low efficiency. We hypothesized that chromatin-modifying agents (CMAs) targeting chromatin acetylation and DNA methylation could alter the chromatin configuration and turn them more amenable to reprogramming. Thus, bovine fibroblasts were treated with 5-aza-2'-deoxycytidine (AZA) plus trichostatin (TSA) or hydralazine (HH) plus valproic acid (VPA) whereas, in another trial, cloned bovine zygotes were treated with TSA. The treatment of fibroblasts with either AZA + TSA or HH + VPA increased histone acetylation, but did not affect the level of DNA methylation. However, treatment with HH + VPA decreased cellular viability and proliferation. The use of these cells as nuclear donors showed no positive effect on pre- and postimplantation development. Regarding the treatment of cloned zygotes with TSA, treated one-cell embryos showed an increase in the acetylation patterns, but not in the level of DNA methylation. Moreover, this treatment revealed no positive effect on pre- and postimplantation development. This work provides evidence the treatment of either nuclear donor cells or cloned zygotes with CMAs has no positive effect on pre- and postimplantation development of cloned cattle.

Local Knowedge and Citizenship: the communitarian health agents

Discussions about the new meaning of citizenship, valuing differences and respecting knowledge diversity bring the question of how public policies can be locally rooted to ensure access to diversity. This is evident when we deal with health policies, where the interaction between implementers and beneficiaries is essential to understand the results of the policy. The Family Health Program (FHP) has tried to change the relationship between state and society, bringing health professionals with the daily experienced by the users where there is (re) production of the components that lead to insecurity, poor health and disease. To analyse this kind of policy we must take into account the interaction processes and the practices of the actors involved in the FHP implementation. This article aims to analyze the role of Health Communitarian Agents (HCA) as FHP implementers. Through ethnographic research followed the practices of ACS in different cities, we seek to understand how they deal with their different knowledge, enable and disable referrals and adapt action to enact the program. We want to understand how they use mediations and interactions in their practices and built policies locally rooted, constructing alternative ways to implement these policies.

Maternal exposure to picrotoxin modifies the response of the GABA(A) receptor during sexual behavior of adult male rat offspring

This study investigated whether perinatal exposure to picrotoxin, a GABA(A) antagonist, modifies the effect of muscimol, a GABA(A) agonist, on the sexual behavior of adult male rats. Two hours after birth and then once daily during the next 9 days of lactation, dams received picrotoxin (0.75 mg/kg subcutaneously) or saline (1 ml/kg subcutaneously). The adult male offspring from the picrotoxin and saline groups received saline (1 ml/kg intraperitoneally) or muscimol (1 mg/kg intraperitoneally), and 15 min later, their sexual behavior was assessed. Muscimol treatment in the saline-exposed group increased the mount and intromission latencies. However, these effects were absent in the picrotoxin-exposed groups. The latencies to first ejaculation, postejaculatory mount, and intromission were decreased in both picrotoxin-exposed groups relative to the saline-exposed groups. The picrotoxin + muscimol-treated rats required more intromissions to ejaculate and the picrotoxin-exposed groups made more ejaculations than the saline-exposed groups. Thus, muscimol treatment did not increase the mount and intromission latencies following picrotoxin exposure, but increased the ejaculation frequency, which did not differ between the picrotoxin + muscimol and the picrotoxin + saline groups. These data indicate that perinatal picrotoxin treatment interfered with GABA(A) receptor development Behavioural Pharmacology 23:703-709 (c) 2012 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

Coupling Between GABA(A)-R Ligand-Binding Activity and Membrane Organization in beta-Cyclodextrin-Treated Synaptosomal Membranes from Bovine Brain Cortex: New Insights from EPR Experiments

Correlations between GABA(A) receptor (GABA(A)-R) activity and molecular organization of synaptosomal membranes (SM) were studied along the protocol for cholesterol (Cho) extraction with beta-cyclodextrin (beta-CD). The mere pre-incubation (PI) at 37A degrees C accompanying the beta-CD treatment was an underlying source of perturbations increasing [H-3]-FNZ maximal binding (70%) and K (d) (38%), plus a stiffening of SMs' hydrocarbon core region. The latter was inferred from an increased compressibility modulus (K) of SM-derived Langmuir films, a blue-shifted DPH fluorescence emission spectrum and the hysteresis in DPH fluorescence anisotropy (A (DPH)) in SMs submitted to a heating-cooling cycle (4-37-4A degrees C) with A (DPH,heating) < A (DPH,cooling). Compared with PI samples, the beta-CD treatment reduced B (max) by 5% which correlated with a 45%-decrement in the relative Cho content of SM, a decrease in K and in the order parameter in the EPR spectrum of a lipid spin probe labeled at C5 (5-SASL), and significantly increased A (TMA-DPH). PI, but not beta-CD treatment, could affect the binding affinity. EPR spectra of 5-SASL complexes with beta-CD-, SM-partitioned, and free in solution showed that, contrary to what is usually assumed, beta-CD is not completely eliminated from the system through centrifugation washings. It was concluded that beta-CD treatment involves effects of at least three different types of events affecting membrane organization: (a) effect of PI on membrane annealing, (b) effect of residual beta-CD on SM organization, and (c) Cho depletion. Consequently, molecular stiffness increases within the membrane core and decreases near the polar head groups, leading to a net increase in GABA(A)-R density, relative to untreated samples.

A transcriptional study in mice with different ethanol-drinking profiles: Possible involvement of the GABA(B) receptor

Previous studies have suggested that gamma-aminobutyric acid-B (GABA(B)) receptor agonists effectively reduce ethanol intake. The quantification using real-time polymerase chain reaction of Gabbr1 and Gabbr2 mRNA from the prefrontal cortex, hypothalamus, hippocampus, and striatum in mice exposed to an animal model of the addiction developed in our laboratory was performed to evaluate the involvement of the GABAB receptor in ethanol consumption. We used outbred, Swiss mice exposed to a three-bottle free-choice model (water, 5% v/v ethanol, and 10% v/v ethanol) that consisted of four phases: acquisition (AC), withdrawal (W), reexposure (RE), and quinine-adulteration (AD). Based on individual ethanol intake, the mice were classified into three groups: "addicted" (A group; preference for ethanol and persistent consumption during all phases), "heavy" (H group; preference for ethanol and a reduction in ethanol intake in the AD phase compared to AC phase), and "light" (L group; preference for water during all phases). In the prefrontal cortex in the A group, we found high Gabbr1 and Gabbr2 transcription levels, with significantly higher Gabbr1 transcription levels compared with the C (ethanol-naive control mice). L, and H groups. In the hippocampus in the A group, Gabbr2 mRNA levels were significantly lower compared with the C, L, and H groups. In the striatum, we found a significant increase in Gabbr1 transcription levels compared with the C, L, and H groups. No differences in Gabbr1 or Gabbr2 transcription levels were observed in the hypothalamus among groups. In summary, Gabbr1 and Gabbr2 transcription levels were altered in cerebral areas related to drug taking only in mice behaviorally classified as "addicted" drinkers, suggesting that these genes may contribute to high and persistent ethanol consumption. (C) 2012 Elsevier Inc. All rights reserved.