First record of Placozoa from the Gulf of Mexico

Placozoa is a phylum with only one species:Trichoplax adhaerens (F. E. Schulze, 1883); recent genetic studies suggest, however,that several haplotypes inhabit tropical and subtropical waters around the world. Placozoans have been found usually close to littoral zones where mangrove forests occur. Goals. To provide the second record of this species from the coasts of Mexico and describe a new filament structure observed in the upper epithelium. Methods. Photographic images were taken of Placozoans found in glass slides introduced in marine aquariums. Some specimens were collected and stained with Mito Tracker, DAPI and Lyso Tracker fluorescent dyes according to the manufacturer instructions. Results. Puerto Morelos in the Mexican Caribbean Sea and Florida in the Atlantic coast are the closest places to the Gulf of Mexico were Placozoans have been recorded. We report here the first record of Trichoplax adhaerens in the Gulf of Mexico. The organisms were found in sea water aquariums built with materials, water, and invertebrates obtained from the Tuxpan reef (21.016667 N, 97.186389 W), an emerged platform that belongs to the Lobos-Tuxpan Reef System. Conclusions. This finding is the first record of Trichoplax for the coasts of the western Gulf of Mexico and includes the description of a filament structure in the upper epithelium not reported before

Development and sedative effect of a new formulation of midazolam in chocolate bars

The aim of this work was to assess the stability and sedative effect of midazolam in chocolate bars. The stability of 5 g chocolate bars containing 6 mg midazolam hydrochloride was evaluated at room temperature (25 ± 2 °C), at 4 and 40 °C, by HPLC. Drug plasma levels were measured and the sedative effect was confirmed in six healthy volunteers according to the Ramsay’s scale. Data regarding chocolate bar administration were compared to those from the apple juice solution. Pharmacokinetic data were processed using the WinNonLin 5.2 software. Midazolam in chocolate bars remained stable for 14 days at room temperature and exposed to light; for 90 days at 4 and 40 °C protected from light, and showed a longer shelf life, better flavour and appearance, inducing the same sedative effect as the apple juice preparation. Raspberry flavour masked midazolam unpleasing taste most favourably.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Development and sedative effect of a new formulation of midazolam in chocolate bars

The aim of this work was to assess the stability and sedative effect of midazolam in chocolate bars. The stability of 5 g chocolate bars containing 6 mg midazolam hydrochloride was evaluated at room temperature (25 ± 2 °C), at 4 and 40 °C, by HPLC. Drug plasma levels were measured and the sedative effect was confirmed in six healthy volunteers according to the Ramsay’s scale. Data regarding chocolate bar administration were compared to those from the apple juice solution. Pharmacokinetic data were processed using the WinNonLin 5.2 software. Midazolam in chocolate bars remained stable for 14 days at room temperature and exposed to light; for 90 days at 4 and 40 °C protected from light, and showed a longer shelf life, better flavour and appearance, inducing the same sedative effect as the apple juice preparation. Raspberry flavour masked midazolam unpleasing taste most favourably.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Indentation Hardness Measurements at Macro-, Micro-, and Nanoscale: A Critical Overview

The Brinell, Vickers, Meyer, Rockwell, Shore, IHRD, Knoop, Buchholz, and nanoindentation methods used to measure the indentation hardness of materials at different scales are compared, and main issues and misconceptions in the understanding of these methods are comprehensively reviewed and discussed. Basic equations and parameters employed to calculate hardness are clearly explained, and the different international standards for each method are summarized. The limits for each scale are explored, and the different forms to calculate hardness in each method are compared and established. The influence of elasticity and plasticity of the material in each measurement method is reviewed, and the impact of the surface deformation around the indenter on hardness values is examined. The difficulties for practical conversions of hardness values measured by different methods are explained. Finally, main issues in the hardness interpretation at different scales are carefully discussed, like the influence of grain size in polycrystalline materials, indentation size effects at micro-and nanoscale, and the effect of the substrate when calculating thin films hardness. The paper improves the understanding of what hardness means and what hardness measurements imply at different scales.Funding Agencies|Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University ((Faculty Grant SFO Mat LiU) [2009 00971]</p

Physicochemical stability of a metformin solution from three commercial brands

Pharmacological management of insulin resistance and dyslipidaemias in children and adolescents is required to prevent the development of metabolic syndrome (MS) and type II diabetes mellitus (DM2). Material and method: we developed extemporaneous formulations from 500 mg-tablets from three generic brands, commercially available in Mexican drugstores: MedimartTM, Farmacias del AhorroTM and Primer NivelTM, dissolved in water sweetened with Splenda, which made them palatable and allowed customised dose adjustment. Solutions were stored at four environmental conditions: 25oC exposed to light, 25oC protected from light, 4oC and 40oC, and their physicochemical stability was assayed. The stability of the drug was determined by ultra performance liquid chromatography and ultraviolet detection (UPLC-UV) and by measuring the pH of the stock solution. The mobile phase consisted of (KH2PO4) 0.1 M, pH = 6.5, 4.6 mM sodium dodecyl sulphate (SDS) and acetonitrile (63:7:30) at 0.8 mL/min, column VARIAN Pursuit C8 150 × 3.9 mm tempered at 40oC, with detection at 236 nm. Results: Metformin from all trademarks was stable at all storage conditions for up to 30 days, retaining more than 90% of the initial amount of active drug, with a pH of 7.4 ± 0.3. Conclusion: Metformin extemporaneous formulations may be developed from either the innovator or generic brands, having the advantage of saving money and conserving the stability of its physicochemical properties. Keywords: Generic metformin, Innovator metformin, Extemporaneous formulation, Physicochemical stability, UPLC-UV