Cytoprotective Mechanisms of DJ-1: Implications in Cardiac Pathophysiology

DJ-1 was originally identified as an oncogene product while mutations of the gene encoding DJ-1/PARK7 were later associated with a recessive form of Parkinson’s disease. Its ubiquitous expression and diversity of function suggest that DJ-1 is also involved in mechanisms outside the central nervous system. In the last decade, the contribution of DJ-1 to the protection from ischemia-reperfusion injury has been recognized and its involvement in the pathophysiology of cardiovascular disease is attracting increasing attention. This review describes the current and gaps in our knowledge of DJ-1, focusing on its role in regulating cardiovascular function. In parallel, we present original data showing an association between increased DJ-1 expression and antiapoptotic and anti-inflammatory markers following cardiac and vascular surgical procedures. Future studies should address DJ-1’s role as a plausible novel therapeutic target for cardiovascular disease.     

Structural colour in animals—simple to complex optics

Over the past 30 years, optics well known to the physicist have been identified in their multitudes in nature. Multilayer reflectors, diffraction gratings, liquid crystals and structures that scatter light—devices explained using “simple” optical theory—have been found in animals with a diversity of designs. For many years the potential to employ these designs commercially has been clear, although only one optical device in animals has been taken through to the manufacture stage—the fly-eye antireflector. Now, with the beginnings of “complex” optical study in biological specimens, and consequent identification of photonic band gaps, animal reflectors are being taken seriously as promising first stages in the design process of optical engineers. However, natural photonic crystals are often highly complex structures at the nano-scale that may lie beyond the limits of current engineering. This in turn justifies the study of cellular engineering—maybe we can also exploit the flawless processes of manufacture employed by animals.     

Aging, rejuvenation and memory phenomena in spin glasses

In this paper, we review several important features of the out-of-equilibrium dynamics of spin glasses. Starting with the simplest experiments, we discuss the scaling laws used to describe the isothermal aging observed in spin glasses after a quench down to the low-temperature phase. We report in particular new results on the sub-aging behaviour of spin glasses. We then discuss the rejuvenation and memory effects observed when a spin glass is submitted to temperature variations during aging, from the point of view of both energy landscape pictures and real-space pictures. We highlight the fact that both approaches point out the necessity of hierarchical processes involved in aging. Finally, we report an investigation of the effect of small temperature variations on aging in spin glass samples with various anisotropies which indicates that this hierarchy depends on the spin anisotropy.     

A quarter century of gyrotron research and development

The development of small-orbit gyrotrons operating at voltages ⩽100 kV is reviewed. Gyrotron oscillators have been developed to produce unprecedented 200-kW average power levels at frequencies spanning the range of 28-140 GHz with current work aimed at achieving 1-MW average power. They are widely used in plasma-heating studies and are the natural choice for material processing in the millimeter-wave region. Gyrotron amplifiers have exceeded the peak power limits of more conventional amplifiers at both 35 and 94 GHz, and have been used in a few radars. Gyro-amplifiers under development have been designed to surpass both the peak power and the average power limits of conventional amplifiers, and are anticipated to be widely accepted in millimeter-wave radar systems. Gyrotron amplifiers operating at voltages ~0.5 MV that are being evaluated for accelerator applications were reviewed in this journal in 1996 and are not included in this review paper,     

A gas-insulated railgun

A railgun concept is discussed in which a high-pressure prefill of hydrogen serves as the close-in insulator between the rails. The gas-insulated railgun (GIRG) approach can reduce or eliminate the velocity-limiting problem of growth and separation of the current-carrying armature region behind the projectile, and thus allow higher launch velocities, to be achieved. A hybrid armature appears appropriate for this launcher     

Scoring methods in MALDI peptide mass fingerprinting: ChemScore, and the ChemApplex program

No universally accepted score is currently available to determine when a matrix-assisted laser desorption ionization (MALDI) peptide mass fingerprint (PMF) experiment has been successfully carried out. We describe a software program (ChemApplex) based on a calculated parameter (Combined Protein Score) that takes into account (1) peak intensity, (2) the mass accuracy of the match, and (3) ChemScore, a theoretical intensity factor that estimates the probability of observing a particular peptide based on a combination of chemical considerations, in particular the amino acid composition of the peptide and the amino acid sequence of the amino acids that span the cleavage site. When these three factors are taken into account both at the level of individual peptides and at the protein level, protein components in mixtures whose peptides contribute less than 1% of the total intensity can often be correctly identified, as is demonstrated for mixtures of standard proteins. Moreover, it is possible to make robust database identifications that are nearly independent of the number of masses submitted and the mass error threshold used for matching. Protein scoring based on Combined Protein Score is orthogonal to many of the commonly used probability-based scoring schemes, and makes it possible to archive a more complete set of parameters that more thoroughly characterize the validity of the database match, which increases the confidence in the identifications.