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

J. Appl. Cryst.の発刊に際して

Peptides or proteins convert under some conditions from their soluble forms into highly ordered fibrillar aggregates. Such transitions can give rise to pathological conditions ranging from neurodegenerative disorders to systemic amyloidoses. In this review, we identify the diseases known to be associated with formation of fibrillar aggregates and the specific peptides and proteins involved in each case. We describe, in addition, that living organisms can take advantage of the inherent ability of proteins to form such structures to generate novel and diverse biological functions. We review recent advances toward the elucidation of the structures of amyloid fibrils and the mechanisms of their formation at a molecular level. Finally, we discuss the relative importance of the common main-chain and side-chain interactions in determining the propensities of proteins to aggregate and describe some of the evidence that the oligomeric fibril precursors are the primary origins of pathological behavior.

/pdf/protein-misfolding-functional-amyloid-and-human-disease-2w386pwb7k.pdf

Protein Misfolding, Functional Amyloid, and Human Disease

We review the dynamical mean-field theory of strongly correlated electron systems which is based on a mapping of lattice models onto quantum impurity models subject to a self-consistency condition. This mapping is exact for models of correlated electrons in the limit of large lattice coordination (or infinite spatial dimensions). It extends the standard mean-field construction from classical statistical mechanics to quantum problems. We discuss the physical ideas underlying this theory and its mathematical derivation. Various analytic and numerical techniques that have been developed recently in order to analyze and solve the dynamical mean-field equations are reviewed and compared to each other. The method can be used for the determination of phase diagrams (by comparing the stability of various types of long-range order), and the calculation of thermodynamic properties, one-particle Green's functions, and response functions. We review in detail the recent progress in understanding the Hubbard model and the Mott metal-insulator transition within this approach, including some comparison to experiments on three-dimensional transition-metal oxides. We present an overview of the rapidly developing field of applications of this method to other systems. The present limitations of the approach, and possible extensions of the formalism are finally discussed. Computer programs for the numerical implementation of this method are also provided with this article.

Dynamical mean-field theory of strongly correlated fermion systems and the limit of infinite dimensions

BIOE 402. Medical Technology Assessment. 2 or 3 hours. Bioentrepreneur course. Assessment of medical technology in the context of commercialization. Objectives, competition, market share, funding, pricing, manufacturing, growth, and intellectual property; many issues unique to biomedical products. Course Information: 2 undergraduate hours. 3 graduate hours. Prerequisite(s): Junior standing or above and consent of the instructor.

“Bioinformatics” 특집을 내면서

Synchrotron radiation is now playing an increasingly important role in recent developments of new light sources. Synchrotron light emitted from a relativistic electron beam has a radiation pattern which makes it a unique source. The advantages with this type of radiation can be summarized as (a) continuous spectrum extending from the ir to the x‐ray region, (b) strongly polarized, (c) highly collimated, (d) pulsed structure allowing time‐resolution spectroscopy, and (e) high intensity making feasible the use of monochromators with narrow band pass. The Stanford Synchrotron Radiation Project has been in operation since May 1974 as a U.S. National Facility for uv and x‐ray research in many disciplines using the radiation from the storage ring SPEAR at the Stanford Linear Accelerator Center. The radiation spectrum is characterized by the critical energy which varies as E3 (E=electron‐beam energy) and is 11 keV for E=4 GeV. Useful flux is available out for approximately five times the critical energy. Five mo...

Synchrotron radiation as a new tool within photon‐beam technology

Anomalous x-ray scattering from terbium-labeled parvalbumin in solution.

We show that the flux line lattice in a model layered high temperature superconductor becomes unstable above a critical magnetic field with respect to a plastic deformation via penetration of pairs of point-like disclination defects. The instability is characterized by the competition between the elastic and the pinning energies and is essentially assisted by softening of the lattice induced by a dimensional crossover of the fluctuations as field increases. We propose that this mechanism provides a model of the low temperature field-driven disordering transition observed in neutron diffraction experiments on Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} single crystals. {copyright} {ital 1996 The American Physical Society.}

https://arxiv.org/pdf/cond-mat/9604171.pdf

Field-Driven Topological Glass Transition in a Model Flux Line Lattice

http://lorentz.dynstr.pasteur.fr/website/publi/jmb_sap1_MD_2000.pdf

Solution structural studies and low-resolution model of the Schizosaccharomyces pombe sap1 protein.

The effects of screening in the core-level photoemission spectra of mixed-valence compounds are studied with the use of an Anderson-model formulation. The mixed-valent ground-state properties and core-hole Green's function are calculated with the use of a decoupling approximation. The relative weights of peaks corresponding to two different configurations (${f}^{n}$ and ${f}^{n+1}$) are found to become appreciably different from the ground-state valence due to shakedown as the hybridization between the localized $f$-level and conduction electrons is increased. The discrepancy is estimated to be of the order of $\frac{V}{{U}_{\mathrm{df}}}$, where ${U}_{\mathrm{df}}$ is the correlation energy between the core hole and $f$ electron, and $V$ represents the hybridization between $f$ electron and conduction electrons. We also find a shakedown ${f}^{n+2}$ peak in this limit. From a comparison of ground-state valence with the measured intensity of the shake-down peak for Ce${\mathrm{Pd}}_{3}$, the width of the $f$ level due to hybridization is estimated to be of the order of 1 eV, in agreement with a recent resonant photoemission measurement.

Sebastian Doniach

Papers

Synchrotron radiation as a new tool within photon‐beam technology

Anomalous x-ray scattering from terbium-labeled parvalbumin in solution.

Field-Driven Topological Glass Transition in a Model Flux Line Lattice

Solution structural studies and low-resolution model of the Schizosaccharomyces pombe sap1 protein.

Screening effects in the core-level spectra of mixed-valence compounds