Renin-expressing cells are peculiar in that they act as differentiated cells, producing the hormone renin, while they also seem to act as progenitors for other renal cell types. As such, they may have functions independent of their ability to generate renin/angiotensin. To test this hypothesis, we ablated renin-expressing cells during development by placing diphtheria toxin A chain (DTA) under control of the Ren1d mouse renin promoter by homologous recombination in a two-renin gene strain ( Ren2 and Ren1d). Renin-expressing cells are essentially absent from kidneys in homozygotes ( DTA/ DTA) which, unlike wild-type mice, are unable to recruit renin-expressing cells when homeostasis is threatened. In contrast, renin staining in the submandibular gland (SMG), which expresses mainly Ren2, is normal. Homozygous mice survive normally, but the kidneys are small and have morphological abnormalities: 25% of the glomeruli are hyperplastic or atrophic, tubules are dilated and atrophic, and areas of undifferentiated cells exist near the atrophic glomeruli and tubules. However, in contrast to the very abnormal renal vessels found when renin-angiotensin system genes are deleted, the kidney vessels in homozygotes have normal wall thickness and no decrease in lumen size. Homozygotes have severely reduced kidney and plasma renin concentrations and females have reduced blood pressure. Homozygotes have elevated blood urea nitrogen and potassium levels, which are suggestive of altered renal function. We conclude that renin cells per se are necessary for the morphological integrity of the kidney and may have a role in maintenance of normal kidney function.

The stability of ascorbyl palmitate, sodium ascorbyl phosphate and magnesium ascorbyl phosphate in topical formulations was investigated by direct reverse phase high performance liquid chromatography after sample dilution with a suitable buffer - organic solvent mixture. Ascorbyl palmitate, sodium ascorbyl phosphate and magnesium ascorbyl phosphate are derivatives of ascorbic acid which differ in hydrolipophilic properties. They are widely used in cosmetic and pharmaceutical preparations. According to the results, ascorbyl esters showed significant differences: sodium ascorbyl phosphate and magnesium ascorbyl phosphate are more stable derivatives of vitamin C than ascorbyl palmitate and may be easily used in cosmetic products.

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Changes in compatibility, tack and viscoelastic properties of ethylene n-butyl acrylate (EBA) copolymer-pentaerythritol rosin ester blend by adding microcrystalline wax, Fischer-Tropsch wax and mixture of waxes, International Journal of Adhesion and Adhesives, http://dx.doi.org/10.1016/j.ijadhadh.2015.11.007 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. AbstractEthylene n-butyl acrylate copolymer (EBA) instead of ethylene vinyl acetate copolymer (EVA) can be used as the base polymer for hot melts. The lower polarity of EBA should affect differently the compatibility with the wax and the tackifier as compared to EVA. In this study the compatibility, tack and viscoelastic properties of EBA copolymer-pentaerythritol rosin ester blended with waxes of different nature (Fischer-Tropsch and microcrystalline) and in different amounts were studied.An increase in compatibility of EBA-copolymer blend with microcrystalline wax was produced leading to increased tack and open time, and reduced viscosity.In contrast, the addition of Fischer-Tropsch wax decreased the compatibility and tack of the EBA-copolymer blend. The addition of a mixture of microcrystalline and Fischer-Tropsch wax caused a better balance in the rheological properties and thermal stability of the EBA-copolymer blends. Finally, an increase in the wax mixture content produced a complete removal of tack caused by dilution of the tackifier in the polymer blend rather than by differences in compatibility.

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a b s t r a c tAn excess of processing oil was intentionally added in the formulation of vulcanized styrene-butadiene rubber for analyzing the effect on the treatment with UV radiation combined with ozone (UV-ozone) in improving the adhesion to waterborne polyurethane adhesive in footwear. Due to the excess of processing oil in the rubber, poor adhesion was expected. Both the length of the treatment and the distance between the UV radiation source to the rubber surface were studied, and the effects of the treatment on the surface chemistry, wettability and surface energy, and topography of the rubber were analyzed. The treatment of the rubber with UV-ozone removed hydrocarbon moieties and zinc stearate from the surface, and surface oxidation (C-O, C¼ O and COO -groups formation) occurred. As a consequence, improved wettability and increased surface energy (mainly due to the polar component of the surface energy) were obtained. The increase in the length of treatment and for a distance of 3-5 cm from the rubber to the UV radiation source favored the effectiveness of the UV-ozone treatment. Besides, whereas the UV-ozone treatment for 3 min produced the ablation of surface contaminants mainly, longer lengths of treatment (i.e., 6-9 min) caused roughness and cracks on the rubber surface. The UVozone treatment also caused heating of the surface. Finally, the treatment with UV-ozone increased the adhesion of the rubber to waterborne polyurethane adhesive, the highest adhesion was obtained in the joints made with UV-ozone treated rubber for 3 and 6 min at a UV radiation source-rubber surface distance of 5 cm.

Viscoelastic and adhesion properties of hotmelts made with blends of ethylene-con -butyl acrylate (EBA) and ethylene-co-vinyl acetate (EVA) copolymers