We have previously identified mouse DDA3 as a p53-inducible gene. To explore the functional role of DDA3, we screened a mouse brain cDNA library by the yeast two-hybrid assay, and identified the microtubule plus-end binding protein EB3 as a DDA3-interacting protein.Binding of DDA3 to EB3 was verified by glutathione S-transferase (GST) pull-down assay and subcellular colocalization; co-immunoprecipitation further indicated that interaction of these two proteins within cells required intact microtubules. Domains of DDA3-EB3 interaction were mapped by GST pull-down assay to amino acids 118-241 and 242-329 of DDA3 and the N-and C-termini of EB3. Immunofluorescence analysis revealed colocalization of DDA3 with microtubules in various cell phases, and regions encompassing aa 118-241 and 242-329 contained microtubule-interacting and bundling activities. In vitro microtubule-binding assay showed that DDA3 and EB3 associated directly with microtubules, and cooperated with each other for microtubule binding. In addition, DDA3 bound to the EB3 interacting partner adenomatous polyposis coli 2 (APC2), a homolog of the tumor suppressor APC, which is a component of the b-catenin destruction complex. Ectopic expression of DDA3 and EB3 enhanced b-catenin-dependent transactivation and cyclin D1 production, whereas knockdown of endogenous DDA3 or EB3 inhibited b-catenin-mediated transactivation and the ability of cells to form colonies. Together, our results identify DDA3 as a novel microtubule-associated protein that binds to EB3, and implicate DDA3 and EB3 in the b-catenin-mediated growth signaling.

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Background: Evidence is lacking regarding the efficacy of macrolides and oral corticosteroids in chronic rhinosinusitis with nasal polyps (CRSwNP) after endoscopic sinus surgery (ESS). Therefore, we examined the benefits of adding clarithromycin to oral prednisolone as post-ESS medical therapy in patients with CRSwNP. Methods:In this randomised, double-blind, placebo-controlled trial, patients were enrolled and allocated to three study groups receiving different post-ESS medical therapies: group A (placebo for 14 weeks), group B (oral prednisolone [15 mg twice daily] for 2 weeks, followed by placebo for 12 weeks), and group C (oral prednisolone [15 mg twice daily] for 2 weeks, followed by clarithromycin [500 mg daily] for 12 weeks). All enrolled patients received the perioperative care following a routine protocol, which included oral amoxicillin/clavulanate, and intranasal corticosteroid spray. The baseline and post-operative visual analogue scale (VAS) scores, Sino-nasal Outcome Test (SNOT-22) scores, and Lund-Kennedy endoscopy scores (LKES) were determined as the primary outcomes.Results: One hundred twenty-six patients who received ESS for bilateral CRSwNP were randomised into group A (n=43), B (n=42), or C (n=41). Compared to groups A and B, group C showed greater VAS and SNOT-22 score improvement at 12 weeks after ESS.Group C showed significantly better LKES than did groups A and B at 8, 12, and 24 weeks after ESS. On stratifying the LKES results according to the presence/absence of tissue eosinophilia, greater add-on effects of clarithromycin were observed in the patient subgroup without tissue eosinophilia. Conclusions:Adding low-dose clarithromycin to oral corticosteroids as post-ESS therapy was well tolerated and showed beneficial subjective and objective outcomes in patients with CRSwNP, especially those without tissue eosinophilia.

The effect of heating on gradation, specific gravity, plasticity characteristics, swelling, and shear strength properties of a kaolin and a bentonite were investigated. The test soils were heated in an electric furnace to different temperatures up to 600°C. The engineering properties were determined by following ASTM standard procedures. Results of the study indicate that heating the kaolin to 400°C reduces the amount of swelling drastically. Further heating to 500°C causes a formation of larger particles, a drop of specific gravity, a change into nonplastic, and a substantial increase in shear strength of the kaolin. For the bentonite, larger particles are found when heated to 600°C. Also, at 600°C, the clay becomes nonplastic and nonexpansive and undergoes a moderate strength gain. Based on the results of the investigation, it is concluded that heating can be used to stabilize soft clay deposits effectively.

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