Nicholas A. Peppas

Bio: Nicholas A. Peppas is an academic researcher from University of Texas at Austin. The author has contributed to research in topics: Self-healing hydrogels & Drug delivery. The author has an hindex of 141, co-authored 825 publications receiving 90533 citations. Previous affiliations of Nicholas A. Peppas include National Technical University & University of Texas System.

Selective recognition of angiotensin II

Abstract: The overexpression of several peptides and proteins in the body often lead to catastrophic physiological conditions. Ultimately it would be beneficial to be able to reduce the circulation of these peptides. One possible method of achieving this is by creating systems that use synthetic biomaterials to mimic natural biological recognition processes. By using synthetic biomaterials, one can design the next generation of materials for therapeutic and diagnostic devices by overcoming barriers posed by natural macromolecules and ligands, which are expensive and relatively unstable. These recognitive polymer systems can be fabricated with molecular architectures possessing specific chemical moieties that provide a framework for selective recognition of a target analyte in aqueous environments. A particular peptide that would benefit from a system such as this is angiotensin II. This is an octapeptide hormone which has been implicated in arterial fibrosis when present in increased levels. This paper reports on a novel recognitive system that uses synthetic biomaterials in order to recognize and capture the undesirable anaylte. Our method uses configurational biomimesis which produces polymeric surfaces or polymeric recognitive networks that have three dimensional, stereospecific binding microand nanocavities based on the given template molecule angiotensin II. To achieve destruction of the overexpressed peptide for further therapeutic effects, we have incorporated biodegradable components into the polymer backbone which creates an acidic microenvironment upon hydrolytic cleavage at ester bonds. This microenvironment will therefore create suitable conditions to destroy the peptide.

Fracture Mechanics of Low Molecular Weight Polymers

Abstract: A novel analysis is presented to explain mechanistic aspects of the fracture of low molecular weight polymers. The fracture energy is calculated as a function of the mean interpenetration distance of a polymer chain which has been derived from the solution of the Fokker-Planck equation. Experimental results with monodisperse polystyrene have been used to validate the theory.

Monte Carlo simulations of grafted chains at interfaces

Abstract: Simulations were carried out of the polymer-polymer chain interpenetration, diffusion, and adhesion of crosslinked polymers with dangling chain ends. Concentration profiles were determined for various polymer chain lengths and densities. The penetration depth was less than the radius of gyration of the polymer grafts or dangling ends and was a function of the packing density and the graft segment length. Limited chain mobility created a stable interfacial zone.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

The Design and Analysis of Experiments

Abstract: THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

Harrison's Principles of Internal Medicine

Abstract: The 11th edition of Harrison's Principles of Internal Medicine welcomes Anthony Fauci to its editorial staff, in addition to more than 85 new contributors. While the organization of the book is similar to previous editions, major emphasis has been placed on disorders that affect multiple organ systems. Important advances in genetics, immunology, and oncology are emphasized. Many chapters of the book have been rewritten and describe major advances in internal medicine. Subjects that received only a paragraph or two of attention in previous editions are now covered in entire chapters. Among the chapters that have been extensively revised are the chapters on infections in the compromised host, on skin rashes in infections, on many of the viral infections, including cytomegalovirus and Epstein-Barr virus, on sexually transmitted diseases, on diabetes mellitus, on disorders of bone and mineral metabolism, and on lymphadenopathy and splenomegaly. The major revisions in these chapters and many

Understanding biophysicochemical interactions at the nano–bio interface

Abstract: Rapid growth in nanotechnology is increasing the likelihood of engineered nanomaterials coming into contact with humans and the environment. Nanoparticles interacting with proteins, membranes, cells, DNA and organelles establish a series of nanoparticle/biological interfaces that depend on colloidal forces as well as dynamic biophysicochemical interactions. These interactions lead to the formation of protein coronas, particle wrapping, intracellular uptake and biocatalytic processes that could have biocompatible or bioadverse outcomes. For their part, the biomolecules may induce phase transformations, free energy releases, restructuring and dissolution at the nanomaterial surface. Probing these various interfaces allows the development of predictive relationships between structure and activity that are determined by nanomaterial properties such as size, shape, surface chemistry, roughness and surface coatings. This knowledge is important from the perspective of safe use of nanomaterials.