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。

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

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

The Design and Analysis of Experiments

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

Harrison's Principles of Internal Medicine

Synthesis and surface engineering of iron oxide nanoparticles for biomedical applications

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.

Understanding biophysicochemical interactions at the nano–bio interface

A new method of crosslinking of polystyrene using difunctional chloromethylated crosslinking agents is reported. The solution crosslinking took place in dichloroethane with SnCl4 as a catalyst at 80°C and with molar ratios of polystyrene to crosslinking agent ranging from 1∶2 to 12∶1. The crosslinked networks prepared by this method had thermal transitions considerably affected by the degree of crosslinking. Ion-exchange resins were prepared by sulfonation of these networks. Water swelling ratios as high as 16.2 were measured leading to indications about the physical structure of these networks.

Structure of friedel-crafts crosslinked polystyrene and sulfonated resins thereof

La liberation de principe actif a partir de systemes a gonflement controle a ete etudiee afin de determiner l'effet de la morphologie du polymere, la composition et les caracteristiques du principe actif sur son mode de liberation. Deux systemes gonflants a base de polyt(2-hydroxyethyl methacrylate-co-methyl methacrylate) reticule, p(HEMA-co-MMA), et d'alcool polyvinylique reticule. PVA. ont ete utilises. Des echantillons de p(HEMA-co-MMA) renfermant de 0 a 100 mol% de HEMA avec des taux de reticulation de 0.005 a 0,10 mol/mol ont ete prepares. Le taux de reticulation nominal a un effet mesurable sur la capture de l'eau dans le PVA reticule. Une bonne correlation existe entre les taux de gonflement et la taille des mailles du reseau gonfle. Des essais de liberation de theophylline, triamterene, chlorhydrate d'oxprenolol. chlorhydrate de buflomedil. vitamine B12, dextran, inuline et myoglobine ont ete realises. Les taux de liberation diminuent avec une augmentation du poids moleculaire du principe actif. Il a ete montre que des temps de relaxation caracteristiques des polymeres ainsi que la vitesse de migration du front dependaient de la composition du polymere, et que la plus grande vitesse de migration du front correspondait aux produits les plus hydrophiles.

Recent studies and molecular analysis of drug release from swelling-controlled devices

The structure of three cross-linked polymers containing naphthalenic rings in their backbone structure was investigated by dynamic swelling and thermal analytic techniques It was determined that the pyridine and n-proplyamine transport in microparticles (40 μm) of these polymers was non-Fickian, often approaching case II transport and sometimes even supercase II transport The thermal analysis showed relatively stable structures up to about 350°C

Transport of penetrants in the macromolecular structure of coals III. Dynamic swelling of stiff polymer networks that simulate the coal structure

Drug Delivery Using Smart Polymers: Recent Advances

The oral administration of hematological factor IX (FIX) can offer a convenient prophylactic treatment for hemophilia B patients. pH-Responsive hydrogels based on poly(methacrylic acid)-grafted-poly(ethylene glycol) (P(MAA-g-EG)) have been engineered as delivery vehicles for FIX. In oral delivery, such hydrogel carriers protected FIX from the gastric environment and released it under intestinal conditions as demonstrated by evaluation of the loading and release of FIX. Tailoring of the hydrogel networks improved the loading of FIX within the microcarriers, which is critical for minimizing protein degradation. Optimizing the loading conditions by increasing the incubation time and using a reduced ionic strength buffer further improved the delivery potential of the microcarriers. The presence of the microcarriers significantly enhanced the oral absorption of FIX in vitro. As shown in this work, P(MAA-g-EG) microcarriers are promising candidates for the oral delivery of FIX.

Nicholas A. Peppas

Papers

Structure of friedel-crafts crosslinked polystyrene and sulfonated resins thereof

Recent studies and molecular analysis of drug release from swelling-controlled devices

Transport of penetrants in the macromolecular structure of coals III. Dynamic swelling of stiff polymer networks that simulate the coal structure

Drug Delivery Using Smart Polymers: Recent Advances

Design of pH-Responsive Biomaterials to Enable the Oral Route of Hematological Factor IX.