Extracorporeal photochemotherapy (photopheresis) induces apoptosis in lymphocytes: a possible mechanism of action of PUVA therapy

The mechanism of action of psoralen plus UVA (PUVA) and photopheresis is not entirely understood. These therapies are assumed to be immunomodulating partly by gradually decreasing leukocyte viability. We investigated whether this delayed form of cell death was due to apoptosis. Untreated and treated (PUVA exposed) leukocytes obtained from six patients with systemic sclerosis and (untreated) leukocytes from healthy control individuals were studied. Qualitative gel electrophoresis and quantitative in situ nick translation analysis of DNA fragmentation was performed. Apoptosis of the treated cells did occur (gel electrophoresis) after 24 h. At t = 0 h, immediately after exposure to PUVA, there was no evidence of DNA fragmentation in the treated cells. The percentage of treated cells undergoing apoptosis was 20-55% at t = 24 h (in situ nick translation). The untreated leukocytes of the patients and the healthy individuals showed no distinctive rise in apoptotic cells. Apoptosis of the leukocytes after PUVA or photopheresis treatment might be a mechanism of action and might explain the therapeutic response.     

Optically and thermally stimulated luminescence characteristics of MgO:Tb3+

In this paper main optically stimulated luminescence (OSL) and thermoluminescence (TL) characteristics are presented of a newly synthesised material MgO doped with terbium (Tb) developed at the Institute of Nuclear Science, Vinca. A thermally stimulated emission spectrum showed the characteristic lines of Tb3+ in a wide range of wavelengths. The TL sensitivity of the main TL glow peak at 315 degrees C is 1.7 times higher than the TL of Al2O3:C. The highest OSL sensitivity was obtained under green lamp (500-570 nm) stimulation. The fast component in the OSL decay curve is 2.4 times faster than Al2O3:C. The OSL signal is linear with dose up to 10 Gy. The lower limit of detection was found to be 100 microGy. These first results show that the newly synthesised material has some promising properties for the application in radiation dosimetry.     

Effects of UVB on the synthesis of complement proteins by keratinocytes

Conditioned taste aversion is a common classic conditioning procedure used to identify noxious stimuli. When a rat is given a taste solution, the conditioned stimulus (CS), followed by an unpleasant experience, the unconditioned stimulus (US), the rat will avoid consumption of the CS in future presentations. These experiments use the taste aversion procedure to examine the effect of exposure to a high magnetic field. A solution consisting of 3.0 g glucose and 1.25 g saccharin per 1 L of solution (G+S) was used as the CS and a 9.4-T magnet served as the US. In Experiment 1, all rats received a 10 min presentation of the G+S solution followed by either a 30 min exposure to the magnetic field (Magnet, n = 8), a 30-min exposure in a container with similar conditions but lacking the magnetic field (Sham, n = 8), or no exposure (Control, n = 8). The Magnet Group showed a taste aversion on the first day of preference testing (p < 0.05). Experiment 2 employed the same US-CS protocol for 3 consecutive days of conditioning. The Magnet Group demonstrated a taste aversion for the postexposure Days 1-8 (p < 0.01). There was no difference between the Sham and Control Groups in either experiment. The results of this study clearly demonstrate that the rats associated the G+S solution with the experience of being exposed to the high magnetic field and avoided the solution in subsequent presentations.     

On the Subjective Quality of Social Justice: The Role of Affect as Information in the Psychology of Justice Judgments.

This article argues that it is not uncommon for people forming justice judgments to lack information that is most relevant in the particular situation. In information-uncertain conditions, people may therefore construct justice judgments by relying on how they feel about the events they have encountered, and justice judgments may hence be strongly influenced by affect information. Findings show that in information-uncertain conditions, the affective states that people had been in prior and unrelated to the justice event indeed strongly influenced their justice judgments. These findings thus reveal that in situations of information uncertainty, people's judgments of justice can be very subjective, susceptible to affective states that have no logical relationship with the justice judgments they are constructing. Implications for the social psychology of justice and the literature on social cognition and affect are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

VH gene family utilization of anti-acetylcholine receptor antibodies in experimental autoimmune myasthenia gravis

The immunoglobulin heavy chain (VH) gene family usage in experimental autoimmune myasthenia gravis (EAMG) model was investigated by RNA slot blot hybridization using VH gene family specific probes. Anti-acetylcholine receptor (AChR) monoclonal antibodies (mAbs) isolated from susceptible C57BL/6 and resistant BALB/c mice were found to be encoded by VH genes from at least six different families. The Vgam3.8 family was overrepresented in alpha-bungarotoxin blocking mAbs. Expression of cross-reactive idiotypes by anti-AChR mAbs was irrespective of the VH gene family usage. Strain dependent differences in susceptibility for EAMG were not reflected in an aberrant VH gene family usage of anti-AChR mAbs.     

Computational Semantics in Discourse: Underspecification, Resolution, and Inference

In this paper I introduce a formalism for natural language understandingbased on a computational implementation of Discourse RepresentationTheory. The formalism covers a wide variety of semantic phenomena(including scope and lexical ambiguities, anaphora and presupposition),is computationally attractive, and has a genuine inference component. Itcombines a well-established linguistic formalism (DRT) with advancedtechniques to deal with ambiguity (underspecification), and isinnovative in the use of first-order theorem proving techniques.The architecture of the formalism for natural language understandingthat I advocate consists of three levels of processing:underspecification, resolution, andinference. Each of these levels has a distinct function andtherefore employs a different kind of semantic representation. Themappings between these different representations define the interfacesbetween the levels.I show how underspecified semantic representations can be built in acompositional way (for a fragment of English Grammar) using standardtechniques borrowed from the -calculus, how inferences can becarried out on discourse representations using a translation tofirst-order logic, and how existing research prototypes (discourseprocessing and spoken-dialogue systems) implement the formalism.     

Ocular torsion quantification with video images

Describes a technique to quantify eye rotations about the visual axis (ocular torsion). Two digitized polar transformed images of the iris are displayed on a video monitor in order to facilitate a visual comparison and manual interaction. Emphasis is placed on error analysis and the method's simplicity when applied to static ocular torsion measurement. The implementation, applying averaging over ocular torsion determined in partitioned iris images, yields a theoretical resolution of 5' of arc. In a control experiment with an artificial eye, the accuracy showed to be better than 14' of arc. In practice, the measuring device was validated with the data from the literature by means of an experiment about ocular torsion in humans during tilt and hypergravity conditions (up to 3 g)     

BEHAVIOUR OF AN ADIABATIC PACKED BED REACTOR PART 2: MODELLING

The steady state and dynamic behaviour of an adiabatic packed bed reactor for the selective hydrogenation of mixtures of ethyne and ethene is studied. A heterogeneous model with axial dispersion of heat is solved numerically by means of a fully implicit discretisation scheme. From an analysis of the inlet and outlet boundary conditions, it follows that in order to avoid an influence of the type of boundary condition on the reactor behaviour, sufficiently long inert zones before and after the active bed should be present. Using preliminary kinetic expressions adapted from Mcn'shchikov ct al. (1975), the model calculations show a reasonable agreement with the experiments performed in a laboratory scale reactor and demonstrate the importance influence of small amounts of carbon monoxide both on the steady state as well as on the transient behaviour of the reactor. However, using the rate expressions derived from our own kinetic experiments in a Berty reactor, the behaviour under runaway conditions and the transition from non-runaway to runaway conditions can not be described well. Several factors that contribute to this discrepancy are discussed. This work shows that, in particular for a complex reaction system such as the selective hydrogenation of ethyne in ethene, the limited accuracy of the kinetic model and kinetic parameters dominates the precision attainable with packed bed reactor models.     

Scalable data structure detection and classification for C/C++ binaries

Many existing techniques for reversing data structures in C/C ++ binaries are limited to low-level programming constructs, such as individual variables or structs. Unfortunately, without detailed information about a program's pointer structures, forensics and reverse engineering are exceedingly hard. To fill this gap, we propose MemPick, a tool that detects and classifies high-level data structures used in stripped binaries. By analyzing how links between memory objects evolve throughout the program execution, it distinguishes between many commonly used data structures, such as singly- or doubly-linked lists, many types of trees (e.g., AVL, red-black trees, B-trees), and graphs. We evaluate the technique on 10 real world applications, 4 file system implementations and 16 popular libraries. The results show that MemPick can identify the data structures with high accuracy.