Abstract Improved methods for non-invasive in vivo assessment are needed to guide development of animal models of atherosclerosis and to evaluate target engagement and in vivo efficacy of new drugs. ...Using novel 3D-micro-ultrasound technology, we developed and validated a novel protocol for 3D acquisition and analysis of imaging to follow lesion progression in atherosclerotic mice. The carotid arteries of ApoE receptor knockout mice and normal control mice were imaged within the proximal 2 mm from the aortic branch point. Plaque volume along that length was quantified using a semi-automated 3D segmentation algorithm. Volumes derived by this method were compared to those calculated using 3-D histology post-mortem. Bland-Altman comparison revealed close correlation between these two measures of plaque volume. Furthermore, using a segmentation technique that captures early positive and 33 week negative remodeling, we found evidence that plaque volume increases linearly over time. Each animal and each plaque served as its own control, allowing accurate comparison. The high fidelity anatomical registration of this protocol provides increased spatial resolution and therefore greater sensitivity for measurement of plaque wall size, an advance over 2-dimensional measures of intimal-medial-thickening. Further, 3-dimensional analysis ensures a point of registration that captures functional markers in addition to the standard structural markers that characterize experimental atherosclerosis. In conclusion, this novel imaging protocol provides a non-invasive, accurate surrogate marker for experimental atherosclerosis over the life of the entire lesion.
Nutrition is a recognized determinant in 3 (ie, diseases of the heart, malignant neoplasms, cerebrovascular diseases) of the top 4 leading causes of death in the United States. However, many health ...care providers are not adequately trained to address lifestyle recommendations that include nutrition and physical activity behaviors in a manner that could mitigate disease development or progression. This contributes to a compelling need to markedly improve nutrition education for health care professionals and to establish curricular standards and requisite nutrition and physical activity competencies in the education, training, and continuing education for health care professionals. This article reports the present status of nutrition and physical activity education for health care professionals, evaluates the current pedagogic models, and underscores the urgent need to realign and synergize these models to reflect evidence-based and outcomes-focused education.
Most health care professionals are not adequately trained to address diet and nutrition-related issues with their patients, thus missing important opportunities to ameliorate chronic diseases and ...improve outcomes in acute illness. In this symposium, the speakers reviewed the status of nutrition education for health care professionals in the United States, United Kingdom, and Australia. Nutrition education is not required for educating and training physicians in many countries. Nutrition education for the spectrum of health care professionals is uncoordinated, which runs contrary to the current theme of interprofessional education. The central role of competencies in guiding medical education was emphasized and the urgent need to establish competencies in nutrition-related patient care was presented. The importance of additional strategies to improve nutrition education of health care professionals was highlighted. Public health legislation such as the Patient Protection and Affordable Care Act recognizes the role of nutrition, however, to capitalize on this increasing momentum, health care professionals must be trained to deliver needed services. Thus, there is a pressing need to garner support from stakeholders to achieve this goal. Promoting a research agenda that provides outcome-based evidence on individual and public health levels is needed to improve and sustain effective interprofessional nutrition education.
A biocompatible polymeric matrix system for the long-term controlled release of dopamine has been developed. Solid particles of this bioactive agent were encapsulated in ethylene-vinyl acetate ...copolymer (EVAc). Following immersion in an aqueous buffer solution, the release rate of dopamine from the polymer matrix was found to depend on the initial concentration of dopamine in the polymer. After coating the matrix devices with an additional impermeable layer of EVAc, constant rates of release were obtained by creating a cavity in this impermeable layer. The observed experiments are consistent with a diffusion-limited model of dopamine release; all the in vitro experimental results were therefore correlated by the effective diffusion coefficient of dopamine through the porous polymer network. These results are discussed in terms of potential design modifications to achieve desired release characteristics for a variety of neuroactive substances, including neurotransmitters or their precursors.
Bone marrow stromal cells (MSCs) are a promising cell source for a variety of tissue engineering applications, given their ready availability and ability to differentiate into multiple cell lineages. ...MSCs have been successfully used to create neotissue for cardiovascular, urological, and orthopedic reconstructive surgical procedures in preclinical studies. The ability to optimize seeding techniques of MSCs onto tissue engineering scaffolds and the ability to control neotissue formation in vitro will be important for the rational design of future tissue engineering applications using MSCs. In this study we investigated the effect of centrifugal force on seeding MSCs into a biodegradable polyester scaffold. MSCs were isolated and seeded onto porous scaffold sections composed of nonwoven polyglycolic acid mesh coated with poly(L-lactide-co-epsilon-caprolactone). Compared to standard static seeding techniques, centrifugal seeding increased the seeding efficiency by 38% (p < 0.007) and significantly improved cellular distribution throughout the scaffold. Overall, centrifugal seeding of MSCs enhances seeding efficiency and improves cellular penetration into scaffolds, making it a potentially useful technique for manipulating neotissue formation by MSCs for tissue engineering applications.
Intracerebral microdialysis was used to evaluate the long-term in vivo release of dopamine from ethylene-vinyl acetate (EVAc)-dopamine copolymer matrix discs for up to 65 days following striatal ...implantation. Dopamine release occurred through a single cavity present on one side of the disc, which was otherwise fully coated with an additional, impermeable layer of EVAc. At 20 days following implantation of the device, extracellular concentrations of dopamine within the striatum reached micromolar levels, over 200-fold greater than control values. Release of dopamine was shown to be stable and maintained for the 2-month duration of the experiment. Histological examination confirmed the biocompatible nature of the implant. There are potential applications of this technology to the treatment of Parkinson's disease and other neurological and psychiatric disorders.
Interior point methods are the right way to solve large linear programs. They are also much easier to derive, motivate, and understand than they at first appeared. Lagrange told us how to convert a ...minimization with equality constraints into an unconstrained minimization. Fiacco and McCormick told us how to convert a minimization with inequality constraints into a sequence of unconstrained minimizations. Newton told us how to solve unconstrained minimizations. Linear programs are minimizations with equations and inequalities. Voila!
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