Animal Models of Calcific Aortic Valve Disease

Calcific aortic valve disease (CAVD), once thought to be a degenerative disease, is now recognized to be an active pathobiological process, with chronic inflammation emerging as a predominant, and possibly driving, factor. However, many details of the pathobiological mechanisms of CAVD remain to be described, and new approaches to treat CAVD need to be identified. Animal models are emerging as vital tools to this end, facilitated by the advent of new models and improved understanding of the utility of existing models. In this paper, we summarize and critically appraise current small and large animal models of CAVD, discuss the utility of animal models for priority CAVD research areas, and provide recommendations for future animal model studies of CAVD

COMPARISON OF ANALYTICAL AND FINITE ELEMENT IMPLEMENTATION OF EXPONENTIAL CONSTITUTIVE MODELS FOR VALVE TISSUE UNDER MICROPIPETTE ASPIRATION SBC2010-19245

INTROUDUCTION Micropipette aspiration (MA) has been widely used to measure the biomechanical properties of cells and biomaterials The goal of this study was to determine whether aortic valve tissue material parameters estimated by the easily-implemented analytical approach [3] differ from those obtained by finite element (FE) analysis aortic valve tissue under MA. To do so, we implemented an exponential hyperelastic constitutive model in the FE model and used an inverse FE approach to predict material parameters METHODS AND MATERIALS Material models To fit the MA experimental measurements of the embryonic atrioventricular cushions, Butcher et al. implemented an exponential constitutive model [2] where W is the strain energy, C and α are material constants and E is the Green's finite strain with the 2 nd Piola-Kirchoff stress (S) being calculated by S = ∂W/∂E. To relate the stress and strain in the constitutive model to experimental measurements, Butcher et al. directly assigned the measured aspiration length (L) to pipette radius (a) ratio as the Green's strain, and the measured aspiration pressure ΔP as the Lagrangian stress T, which is calculated by T = λS with the stretch ratio in the aspiration direction (λ) given by λ = (E + 1) 0.5 To account for the multicomponent stress-strain field in the valve tissue during MA process, we implemented an incompressible isotropic exponential constitutive model. The strain energy density function of this model is expressed as where W is the strain energy, C and α are material constants and I 1 is the first strain invariant, defined as I 1 = with λ 1 , λ 2 and λ 3 being the principal stretches. This isotropic exponential constitutiv

Mechanisms of MEOX1 and MEOX2 Regulation of the Cyclin Dependent Kinase Inhibitors p21CIP1/WAF1 and p16INK4a in Vascular Endothelial Cells

Senescence, the state of permanent cell cycle arrest, has been associated with endothelial cell dysfunction and atherosclerosis. The cyclin dependent kinase inhibitors p21CIP1/WAF1 and p16INK4a govern the G1/S cell cycle checkpoint and are essential for determining whether a cell enters into an arrested state. The homeodomain transcription factor MEOX2 is an important regulator of vascular cell proliferation and is a direct transcriptional activator of both p21CIP1/WAF1 and p16INK4a. MEOX1 and MEOX2 have been shown to be partially functionally redundant during development, suggesting that they regulate similar target genes in vivo. We compared the ability of MEOX1 and MEOX2 to activate p21CIP1/WAF1 and p16INK4a expression and induce endothelial cell cycle arrest. Our results demonstrate for the first time that MEOX1 regulates the MEOX2 target genes p21CIP1/WAF1 and p16INK4a. In addition, increased expression of either of the MEOX homeodomain transcription factors leads to cell cycle arrest and endothelial cell senescence. Furthermore, we show that the mechanism of transcriptional activation of these cyclin dependent kinase inhibitor genes by MEOX1 and MEOX2 is distinct. MEOX1 and MEOX2 activate p16INK4a in a DNA binding dependent manner, whereas they induce p21CIP1/WAF1 in a DNA binding independent manner

A communal catalogue reveals Earth's multiscale microbial diversity

Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.Peer reviewe

A communal catalogue reveals Earth’s multiscale microbial diversity

Our growing awareness of the microbial world’s importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth’s microbial diversity

Comparative antiplaque and antigingivitis efficacy of a multipurpose essential oil-containing mouthrinse and a cetylpyridinium chloride-containing mouthrinse: A 6-month randomized clinical trial

Made available in DSpace on 2019-09-12T16:57:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2012Johnson & Johnson Consumer & Personal Products Worldwide (Division of Johnson & Johnson Consumer Companies)Objective: This 6-month, examiner-blind, single-center, randomized, parallel group clinical trial compared the antiplaque and antigingivitis effects of an essential oil-containing mouthrinse with zinc chloride and sodium fluoride (EO) to a 0.05% cetylpyridinium chloride-containing mouthrinse (CPC) also with fluoride. Method and Materials: Four hundred and eight gingivitis subjects were monitored for the primary outcomes of modified Gingival Index (MGI) and Plaque Index (PI) at baseline and 3 and 6 months. Subjects were randomly assigned to 6-month twice a day unsupervised use of EO, CPC, or negative control rinse in conjunction with normal brushing and flossing. Results: EO was always better than CPC at 3 and 6 months considering all parameters. All benefits allowed by EO increased from 3 to 6 months. CPC was better than the negative control at 3 and 6 months with respect to whole mouth plaque, and the proportion of more severe sites (baseline scores >= 3) in PI and MGI. At 6 months, CPC did not differ from negative control in relation to whole mouth MGI reduction, proximal MGI reduction, and percentages of sites improved over baseline in PI and MGI. Conclusion: This new EO mouthrinse provided superior clinical benefits to CPC and demonstrated increasing plaque and gingivitis reductions over 6 months. Our findings support the regular long-term use of the EO mouthrinse and selection over a 0.05% CPC rinse for better efficacy. (Quintessence Int 2012; 43:e82-e94)[Cortelli, Sheila Cavalca; Cortelli, Jose Roberto] Universidade de Taubaté (Unitau), Dept Periodontol[Wu, Mei-Miau] Johnson & Johnson Consumer & Personal Prod Worldw, Biostat Biometr & Clin Data Syst, Morris Plains, NJ USA[Simmons, Krista] Johnson & Johnson Consumer & Personal Prod Worldw, Oral Care Res Dev & Engn, Morris Plains, NJ USA[Charles, Christine Ann] Johnson & Johnson Consumer & Personal Prod Worldw, Sci & Profess Affairs, Oral Care Res Dev & Engn, Morris Plains, NJ US