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Esophageal cancer (EC) is an aggressive disease, presenting two main histological subtypes: adenocarcinoma (EAC) and squamous cell carcinoma (ESCC). The two EC subtypes widely differ concerning virtually all factors. ESCC development is mainly associated with tobacco and alcohol abuse, whereas obesity and chronic gastroesophageal reflux disease (GERD) are important risk factors not only for EAC, but also for for Barrett's esophagus (BE), an intestinal metaplasia that precedes EAC. Obesity triggers ectopic lipid droplets (LD) accumulation in non-adipose tissues. LD are organelles involved in cell metabolism, signaling, proliferation and production of inflammatory mediators. Therefore, the aim of this work was to investigate LD occurrence and role in EC. This study shows progressive LD levels increase along EAC development, in esophageal samples from non-obese through obese individuals, as well as BE, and EAC patients, whereas no significant changes were observed in ESCC samples, when compared to non-tumor samples. Additionally, in order to mimic BE and EAC risk factors exposure, a non-tumor esophageal cell line was incubated with oleic acid (OA) and acidified medium and/or deoxycholic acid (DCA), revealing a significant increment in LD amount as well as in COX-2 and CXCL-8 expression, and in IL-8 secretion. Further, COX-2 expression and LD amount presented a significant positive correlation and were detected co-localized in EAC, but not in ESCC, suggesting that LD may be the site for eicosanoid production in EAC. In conclusion, this study shows that obesity, and BE- and EAC-associated inflammatory stimuli result in a gradual increase of LD, that may be responsible for orchestrating inflammatory mediators' production and/or action, thus contributing to BE and EAC genesis and progression.

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ABSTRACT Acheflan® herbal medicine is the first medicine developed and produced in Brazil using Cordia verbenacea DC., Boraginaceae, essential oil as a constituent. C. verbenacea has anti-inflammatory properties, which have been directly related to α-humulene and trans-caryophyllene. Currently, the quantification of α-humulene and trans-caryophyllene in C. verbenacea has only been described by GC-MS. Although this technique is widely used it cannot be directly applied to finished medicinal products since they contain aqueous constituents. In this context, the objective of this work was to develop a methodology for quantifying C. verbenacea in raw materials and in pharmaceutical formulations using liquid chromatography. The Box-Behnken experimental design was used successfully to optimize the analytical method. The method developed in this study was validated and proven to be effective in the proper separation of α-humulene and trans-caryophyllene. In addition, the developed method was applied to commercial formulations (cream and aerosol) containing C. verbenacea essential oil, which resulted in very satisfactory separation without interference from excipients. C. verbenacea oil contains four times higher concentrations of trans-caryophyllene than α-humulene. Therefore, we propose that trans-caryophyllene can be used as a marker of C. verbenacea essential oil. Evaluation of trans-caryophyllene content would be especially valuable for applications where the concentrations are very low such as in permeation and release studies of dermatological formulations.

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THE OBJECTIVE: To assess in vitro the cariogenic and erosive potentials of Brazilian liquid oral paediatric medicines. SETTING: Twenty-three paediatric medicines available on the Brazilian market were evaluated. The sample consisted of antihistamines, antitussives, bronchodilators and mucolytics. MAIN OUTCOME MEASURES: Duplicates of each bottle were analyzed for sugar concentration using normal-phase- high-performance liquid chromatography (HPLC). Quantification of sugars and sorbitol was calculated using the peak heights of commercial standards as references. pH measurements were determined using a digital pH meter. Titratable acidity was assessed by diluting three aliquots of each medicine, and increments of 0.1N NaOH were titrated until neutrality was reached. Viscosity was determined using a viscosemeter. RESULTS: Sugars were detected in 56.5% of the medicines. Sucrose was identified in 10 medicines, with concentrations ranging from 11.36 g% to 85.99 g%. Glucose was detected in five medicines, with concentrations varying from 4.64 g% to 40.19 g%; fructose in six medicines, with concentrations ranging from 5.09 g% to 46.71 g%. Twelve medicines exhibited sorbitol, with values ranging from 5.39 g% to 46.09 g%. Most tested medicines were acidic, with pH values ranging between 2.6 and 5.7. Only two medicines (Fluimucil and Polaramine) presented pH 6.4 and 6.0, respectively. Titratable acidity mean values ranged between 0.28 and 16.33 mL. Viscosity values varied between 2.8 cP and 412.3 cP. CONCLUSIONS: Many paediatric medicines showed high sugar concentration, pH values below the critical value and high titratable acidity values, all of which increase the medicines' cariogenic and erosive potentials.

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In this study, two methods, based on high-performance liquid chromatography (HPLC) and UV spectrophotometry, were developed and validated for the quantitative determination of lumiracoxib in tablets. The HPLC was carried out on a column of propylsulfonic acid bonded to silica gel (250 x 4.6 mm; 5 mium), with a mobile phase of phosphate buffer (pH 7.4; 10 mM)-water-acetonitrile (10:40:50, v/v/v) fl owing at 1.0 mL/min and detection of the drug at 278 nm. The UV method was based on absorbance at 275 nm, with ethanol as solvent. Both assays were linear over the concentration range of 2–30 miug/mL (R approximate 0.999), as wellas accurate and precise, with recoveries between 98 and 100% and relative standard deviation (%RSD) smaller that 2.0%. The proposed methods are highly sensitive, precise and accurate and were successfully applied to the quantitation of lumiracoxib in the commercial formulation. The spectrophotometric method is a simple, cheap and less time-consuming method. However, the chromatographic method is selective for the determination of the degradation products of lumiracoxib.

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The purpose of this study was to develop a new configuration for a compact on-site treatment system, which could become an attractive alternative, from technical, economic, social and environmental viewpoints, to the technologies that are currently employed. The treatment unit consists of a cylindrical tank, where half of the volume is used as a modified septic tank and the other half is divided between an anaerobic hybrid reactor and a trickling filter. An intermittent feeding system was used, with minimum, mean and maximum flowrate settings (Qmin = 0.25l.s(-1), Qmean = 0.50l.s(-1) and Qmax = 1.00l.s(-1)), to reflect the actual operating conditions of a compact on-site treatment system serving a typical dwelling. An average 24-hour hydraulic detention time was used, corresponding to a flowrate of 750l.d(-1). High removal efficiencies and low concentrations of COD, BOD and TSS in the final effluent were achieved, even when the unit was exposed to hydraulic loading peaks during feeding periods at maximum flowrate.

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Mutants of each of the four divalent cation binding sites of chicken skeletal muscle troponin C (TnC) were constructed using site-directed mutagenesis to convert Asp to Ala at the first coordinating position in each site. With a view to evaluating the importance of site-site interactions both within and between the N- and C-terminal domains, in this study the mutants are examined for their ability to associate with other components of the troponin-tropomyosin regulatory complex and to regulate thin filaments. The functional effects of each mutation in reconstitution assays are largely confined to the domain in which it occurs, where the unmutated site is unable to compensate for the defect. Thus the mutants of sites I and II bind to the regulatory complex but are impaired in ability to regulate tension and actomyosin ATPase activity, whereas the mutants of sites III and IV regulate activity but are unable to remain bound to thin filaments unless Ca2+ is present. When all four sites are intact, free Mg2+ causes a 50-60-fold increase in TnC's affinity for the other components of the regulatory complex, allowing it to attach firmly to thin filaments. Calcium can replace Mg2+ at a concentration ratio of 1:5000, and at this ratio the Ca2.TnC complex is more tightly bound to the filaments than the Mg2.TnC form. In the C-terminal mutants, higher concentrations of Ca2+ (above tension threshold) are required to effect this transformation than in the recombinant wild-type protein, suggesting that the mutants reveal an attachment mediated by Ca2+ in the N-domain sites.

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