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In addition to their well-known classical effects, cannabinoid CB1 and CB2 receptors have also been involvement in both deleterious and protective actions on the heart under various pathological conditions. While the potential therapeutic applications of the endocannabinoid system in the context of cardiovascular function are indeed a viable prospect, significant debate exists within the literature regarding whether CB1, CB2, or a combination of both receptors exert a favorable influence on cardiac function. Hence, the aim of this study was to investigate the effects of CB1 + CB2 or CB2 agonists on cardiac excitation-contraction (E-C) coupling, utilizing fish (Brycon amazonicus) as an experimental model. The CB2 agonist elicited marked positive inotropic and lusitropic responses in isolated ventricular myocardium, induced cyclic adenosine 3′,5′-monophosphate (cAMP) production, and upregulated critical Ca2+ handling proteins, such as sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) and Na+/Ca2+ exchanger (NCX). Our current study demonstrated, for the first time, that CB2 receptor activation-induced effects improved the efficiency of Ca2+ cycling, excitation-contraction coupling (E-C coupling), and cardiac performance in under physiological conditions. Hence, CB2 receptors could be considered a potential therapeutic target for modulating cardiac contractile dysfunctions. [Display omitted] • Activation of CB2 receptors improves cardiac contractile performance. • CB2 agonist treatment induces the expression of Ca2+ handling proteins. • Activation of CB2 receptors increases cardiac cAMP production. • CB2 receptor activation improves the efficiency of Ca2+ cycling. [ABSTRACT FROM AUTHOR]

To evaluate the cyclooxygenases (COX) inhibition, adverse effects and analgesic efficacy of dipyrone or meloxicam in cats undergoing elective ovariohysterectomy. Prospective, blinded, randomized, clinical study. A total of 30 healthy young cats. The cats were randomly assigned to three postoperative groups: D25 (dipyrone 25 mg kg−1 every 24 hours), D12.5 (dipyrone 12.5 mg kg−1 every 12 hours) and M (meloxicam 0.1 mg kg−1 every 24 hours). In the first 24 hours, the drugs were administered intravenously (IV), and then orally for 6 (dipyrone) or 3 days (meloxicam). Prostanoids thromboxane B 2 and prostaglandin E 2 concentrations served as indicators of COX activity and, with physiological variables and pain and sedation scores, were measured for 24 hours after first analgesic administration. Rescue analgesia (tramadol, 2 mg kg−1 IV) was provided if Glasgow feline composite measure pain scale (CMPS-Feline) ≥5. Laboratory tests included symmetric dimethylarginine and adverse effects were evaluated regularly up to 7 and 10 days after surgery, respectively. Parametric and nonparametric data were analyzed with two-way anova and Kruskal-Wallis tests, respectively (p < 0.05). In the first half hour after analgesic administration, COX-1 activity was close to zero and remained significantly lower than before drug administration for 24 hours in all groups. The inhibition of COX-2 activity was significant for 30 minutes in all groups and up to 4 hours in group M. No alterations in laboratory tests or significant adverse effects were observed. Pain scores and need for rescue analgesia did not differ statistically among groups. Dipyrone at both doses and meloxicam provided a nonselective inhibition of COX-1 and -2 activities and effective analgesia without causing significant adverse effects or laboratory tests alterations. Dipyrone at both doses provides equally effective analgesia without causing adverse effects in cats undergoing ovariohysterectomy. [ABSTRACT FROM AUTHOR]

To evaluate the addition of dimethylaminohexadecyl methacrylate (DMAHDM) and chlorhexidine diacetate on cytotoxicity, antimicrobial activity, physical, and mechanical properties of a self-cured resin. 132 disk-shaped and 48 rectangular specimens were divided into four experimental groups as described: Control Group (CG – no addition), dCHX (1%), DMAHDM (5%), and DMAHDM + dCHX (5% + 1%). The biofilm viability, flexural strength (FS - ISO 20795-1:2013), surface roughness (SR), and color stability (ΔE) were analyzed after being stored for 4 weeks in distilled water and immersed for 72 h in coffee. Cytotoxicity was measured after 24 h, 3, and 7 days of elution using an MTT test on L929 cells (ISO 10993-5:2009). SR and ΔE were measured by a contact profilometer and a spectrophotometer using the CIELab parameter. Data were submitted to ANOVA and Bonferroni's/Tukey's tests (p ≤ 0.05). Significant antimicrobial activity against Streptococcus mutans and Candida albicans was detected in all groups when compared to the CG (p < 0.05). Only the dCHX group, in 24 h of elution, demonstrated no cytotoxicity effects. There was a statistical difference for FS on the tested groups (p < 0.05). No differences were detected in the initial roughness' measurements among the groups (p > 0.05). However, after storage and immersion in coffee, the groups containing DMAHDM presented with rougher surfaces and significantly lower color stability compared to the control (p < 0.05). The addition of dCHX and DMAHDM in self-cured resin presented antimicrobial properties; however, cytotoxicity, physical, and mechanical properties were compromised. [ABSTRACT FROM AUTHOR]

Abstract In this work Cu, Sn, and Ti nanoparticles were incorporated into solutions for the sol-gel deposition of silica coatings on coked alumina substrates. Cu Sn Ti ternary alloys were used aiming to improve the chemical affinity between silica and water. After heat treatment in an argon atmosphere, the coating adherence on samples was examined by scanning electron microscopy (SEM), scratch, and tape tests. The wettability behavior of the prepared materials was also investigated. It was observed that the presence of silica coatings on coked substrates increased their affinity for water. It is an important result since the hydrophobic behavior of coked linings inhibits the deposition of repair materials on their surface, which decreases their life sDpan and leads to financial losses in petrochemical applications. Evaluation of the samples by SEM indicated the presence of a nearly uniform silica film on the coated substrates. Moreover, tape and scratch tests indicated that there was good adhesion between the silica coatings and alumina substrate because no delamination or peeling was observed in these tests. The use of a Cu Sn Ti alloy composed of 60 wt%Cu−35 wt%Sn−5 wt%Ti led to smoother materials when compared to a 40 wt%Cu−50 wt%Sn−10 wt%Ti alloy. Nonetheless, no difference in terms of roughness was noticed for specimens heat treated at 110, 750 or 1050 °C. [ABSTRACT FROM AUTHOR]

Highlights: [•] Post mortem study of refractory lining used in FCC units. [•] Samples also collected from an unused refractory lining for comparison purposes. [•] Samples obtained from hot side regions usually show higher volume fractions of coke. [•] Coke observed in samples collected from used linings is a carbon black-like material. [•] The presence of coke led to a partial obstruction of the refractory pores. [Copyright &y& Elsevier]

Abstract: Carbon-containing refractory materials have received great attention over the last years due to their importance in the steelmaking process. The oxidation of carbon present in refractory materials at temperatures above 500°C is usually accompanied by the decrease of their mechanical strength and chemical resistance. Aiming to improve the oxidation resistance of carbon-oxide refractories, the use of materials known as antioxidants has been extensively studied. In this work we evaluated the performance of MgB2 and B4C antioxidants when incorporated into MgO–C bricks. We observed that the co-addition of metallic antioxidants and B4C or MgB2 leads to refractory bricks with enhanced hot modulus of rupture and resistance against oxidation and slag corrosion. However, the excessive addition of these antioxidants could impair the performance of the obtained bricks. Thus, when determining the optimum concentration of MgB2 and B4C to be added into MgO–C refractories, one must take into consideration this behavior. [Copyright &y& Elsevier]

Natural dyes composed by anthocyanins extracted from natural Caribbean species S. cumini , were employed to evaluate their effects on the photocatalytic properties of TiO 2 thin films. The qualitative and quantitative analyses of the anthocyanins were carried out using high-performance liquid chromatography with photodiode array detection (HPLC-DAD). From the chemical characterization of the S. cumini extract three main anthocyanins were identified and the most abundant compound was delphinidin-3,5-diglucoside (44%). The total anthocyanin content expresses as delphinidin chloride (TAEDC) per mL of the extract was equal to 124 ± 5 μg TAEDC/mL. After the identification, a sensitization process was performed and verified by infrared spectroscopy (IR) and absorption diffuse reflectance. Afterwards, the Methylene Blue photodegradation process was studied under visible light irradiation on the S. cumini- sensitized TiO 2 material (TiO 2 / S. cumini ). The results indicated that the photocatalytic activity of the sensitized material TiO 2 / S. cumini was ∼3 times greater than unmodified TiO 2 thin films, which let us to propose that the extract from Caribbean Colombian S. cumini could have a great potential as source of photosensitizers for photocatalytic applications. Finally, the electronic structure of each anthocyanin found in the extract (delphinidin-3,5-diglucoside, malvidin-3-5-diglucoside and petunidin-3-5-diglucoside) and their interaction with a TiO 2 model was studied by means of the density functional theory (DFT). [ABSTRACT FROM AUTHOR]