Abstract. Celecoxib (Cx) shows high efficacy in the treatment of osteoarthritis and rheumatoid arthritis as a result of its high specificity for COX-2, without gastrolesivity or interference with platelet function at therapeutic concentrations. Besides of anti-inflammatory effects, Cx also has a potential role for oral cancer chemoprevention. For these conditions, oral administration in long-term treatment is a concern due to its systemic side effects. However, local application at the site of injury (e.g., buccal inflammation conditions or chemoprevention of oral cancer) is a promising way to reduce its toxicity. In this study, the in vitro characterization of mucoadhesive chitosan (CHT) gels associated to Azone® was assessed to explore the potential buccal mucosal administration of Cx in this tissue. Rheological properties of gels were analyzed by a rheometer with cone-plate geometry. In vitro Cx release and permeability studies used artificial membranes and pig cheek mucosa, respectively. Mucoadhesion were measured with a universal test machine. CHT gels (3.0%) containing 2.0% or 3.0% Az showed more appropriate characteristics compared to the others: pH values, rheology, higher amount of Cx retained in the mucosa, and minimal permeation through mucosa, besides the highest mucoadhesion values, ideal for buccal application. Moreover, the flux (J) and amounts of drug released decreased with increased CHT and Az concentrations. CHT gels (3.0%) associated with 2.0% or 3.0% Az may be considered potential delivery systems for buccal administration of Cx.

The aim of the present study was to evaluate the insecticidal effect of the cassia, thyme and oregano volatile oils against the immature and adult flea's stages. For this purpose, the tested samples were chemically characterized by GC-FID and GC-MS. The mortality of larvae and adult fleas, eggs, and pupae of Ctenocephalides felis felis was performed through in vitro tests at different concentration levels. Inhibition of development and residual efficacy were also determined. The chemical characterization of the cassia, thyme, and oregano volatile oils presented cinnamaldehyde (91%), thymol (44.7%), and carvacrol (76.2%), respectively, as major constituents. In general, the samples showed insecticidal activity for both immature and adult flea's stages. The best LC 50 values for adults were obtained by oregano volatile oils (33.5 and 21.8 μg•cm −2 , respectively, 24 and 48 h). Cassia volatile oils showed the best results against larvae (17.2 and 10.3 μg•cm −2 , respectively, 24 and 48 h), eggs (3 μg.cm −2), and pupae (34.6 μg•cm −2), as well as the lowest value for inhibition of development (2.3 μg•cm −2). The oregano and thyme volatile oils showed residual efficacy greater than 80% for 6 days while cassia showed this result for 4 days. The results demonstrated the potential of volatile oils for flea control in all stages of the life cycle, with emphasis on cassia. The residual effects of the volatile oils are promising for the development of new and environmentally friendly phyto-pesticides for veterinary uses.

Extracts and essential oils from plants are important natural sources of pesticides. These compounds are considered an alternative to control ectoparasites of veterinary importance. Schinus molle, an endemic species of Brazil, produces a high level of essential oil and several other compounds. The aim of this work was to determinate the chemical composition of extracts and essential oils of S. molle and further to evaluate the activity against eggs and adults of Ctenocephalides felis felis, a predominant flea that infests dogs and cats in Brazil. In an in vitro assay, the non-polar (n-hexane) extract showed 100% efficacy (800 µg cm(-2); LD50 = 524·80 µg cm(-2)) at 24 and 48 h. Its major compound was lupenone (50·25%). Essential oils from fruits and leaves were evaluated, and had 100% efficacy against adult fleas at 800 µg cm(-2) (LD50 = 353·95 µg cm(-2)) and at 50 µg cm(-2) (LD50 = 12·02 µg cm(-2)), respectively. On the other hand, the essential oil from fruits and leaves was not active against flea eggs. This is the first study that reports the insecticidal effects of essential oils and extracts obtained from Schinus molle against Ctenocephalides felis felis.

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This paper aims to gather and discuss important information about nonylphenol, such as physical chemistry properties, toxicity and analytical methods in various matrices. As a degradation product of ethoxylated alkylphenols, nonylphenol presents a higher degree of reactivity than its precursor. Due to its harmful effects on the environment, use and production of nonylphenol has been banned in European Union countries, alongside their precursors. The guide on quality of drinking water (USEPA) recommends a maximum concentration of 28 µg L -1 for fresh water. In Brazil, there is no clear legislation containing values of maximum concentration of nonylphenol. Due to this lack of regulation, a continuous monitoring is necessary of this pollutant in environmental samples. This paper aims to encourage further studies on nonylphenol, seen as a critical environmental pollutant. For proper monitoring is necessary to have reliable analytical methods and easy to perform in routine analysis.