bluuebunny/crossref_metadata_2025 huggingface dataset:
Gauge-Theory Approach to Planar Doped Antiferromagnets and External Magnetic Fields
Authors: Farakos K. , Mavromatos N. E.
Published: June 2003

Within the framework of a relativistic non-Abelian gauge theory approach to the physics of spin–charge separation in doped quantum antiferromagnetic planar systems, proposed recently by the authors, we are examining here the effects of constant external magnetic fields on excitations about the superconducting state in the model. The electrically-charged Dirac fermions (holons), describing excitations about specific points on the fermi surface, e.g. those corresponding to the nodes of a d-wave superconducting gap in high-T c cuprates, condense, resulting in the opening of a Kosterlitz–Thouless–like gap (KT) at such nodes. This leads, in general, to a second superconducting phase transition, which occurs at low temperatures[Formula: see text], in addition to the high-T c superconductivity [Formula: see text] due to the bulk of the fermi surface for holons in a (d-wave) spin–charge separated superconductor. In the presence of strong external magnetic fields at the surface regions of the planar superconductor, in the direction perpendicular to the superconducting planes, these KT gaps appear to be enhanced. Our preliminary analysis, based on analytic Schwinger–Dyson treatments, seems to indicate that for an even number of Dirac fermion species, required in our model as a result of gauging a particle–hole SU(2) symmetry, Parity or Time Reversal violation does not necessarily occurs. Based on these considerations, we argue that recent experimental findings, concerning thermal conductivity plateaux of quasiparticles in planar high-T c cuprates in strong external magnetic fields, may indicate the presence of such KT gaps, caused by charged Dirac-fermion excitations in these materials, as suggested in the above model.
Weakly Nonlinear Investigation of the Saffman–Taylor Problem in a Rectangular Hele–Shaw Cell
Authors: Miranda José A. , Widom Michael
Published: June 2003

We analyze the Saffman–Taylor viscous fingering problem in rectangular geometry. We investigate the onset of nonlinear effects and the basic symmetries of the mode coupling equations, highlighting the link between interface asymmetry and viscosity contrast. Symmetry breaking occurs through enhanced growth of sub-harmonic perturbations. Our results explain the absence of finger tip-splitting in the early flow stages, and saturation of growth rates compared with the predictions of linear stability.
Properties of Derivative Expansion Approximations to the Renormalization Group
Authors: Morris T. R.
Published: June 2003

Approximation only by derivative (or more generally momentum) expansions, combined with reparametrization invariance, turns the continuous renormalization group into a set of partial differential equations which at fixed points become nonlinear eigenvalue equations for the anomalous scaling dimension η. We review how these equations provide a powerful and robust means of discovering and approximating non-perturbative continuum limits. Gauge fields are briefly discussed. Particular emphasis is placed on the rôle of reparametrization invariance, and the convergence of the derivative expansion is addressed.
An Overview of the Direct Thrombin Inhibitor Argatroban
Authors: Walenga Jeanine M.
Published: June 2003

Argatroban is a small molecule direct thrombin inhibitor. The main attributes of this synthetic drug are its rapid onset of anti-thrombin action, rapid reversibility of its anticoagulant effect, potent inhibition of clot-bound thrombin, absence of antibody formation and no need for initial dosage adjustment in patients with renal impairment. It is eliminated by hepatic metabolism. These properties make argatroban a predictable anticoagulant with intravenous use in a routine clinical setting. Argatroban is approved in the US and Canada for both prophylaxis and treatment of thrombosis in patients with heparin-induced thrombocytopenia (HIT); and it is approved in Japan and Korea for treatment of various thrombotic disorders. Argatroban has been shown in limited trials to provide reliable anticoagulation during percutaneous coronary interventions on HIT and non-HIT patients. Preliminary reports document the feasibility of using argatroban for anticoagulation during peripheral vascular interventions, hemodialysis and as adjunct to thrombolysis for treatment of myocardial infarction. Current recommendations for argatroban monitoring are to use the activated partial thromboplastin time for low doses and the activated clotting time for high doses. The ease of monitoring argatroban, its ‘turn-on/turn-off’ characteristic and its consistent safety profile provide the rationale to continue studies of argatroban as an anticoagulant in clinical settings.
Historical Perspective of the Development of Thrombin Inhibitors
Authors: Markwardt Fritz
Published: June 2003

Progress in molecular biology has stimulated interest in the structure and function of thrombin. It has improved our understanding of its central role in thrombogenesis and has clarified the molecular events of inhibitor binding. This development has resulted in the production of recombinant hirudins and hirudin analogues. It has also allowed the molecular design of synthetic antithrombins, and encouraged the development of these products for clinical use. All pharmacological aspects speak in favor of the use of direct thrombin inhibitors as antithrombotic agents, especially in the potential indications where thrombin plays a crucial pathogenetic role. If their apparent advantages compared with heparin can be definitely demonstrated, the direct thrombin inhibitors may become the drug of choice for certain indications.
Current Perspective on Antithrombin Drugs
Authors: McGregor John L.
Published: June 2003

Thrombin is a multifunctional serine protease, which is involved in blood coagulation and thrombosis, inflammation and wound repair in tissue injury. Its role in the amelioration of inflammatory tissue injury has been investigated. Protease-activated cell surface receptors (PARs) when activated by thrombin result in the production of proinflammatory mediators. In the kidney, these PARs are expressed on the glomerular epithelium and the vascular endothelium. The significant impact of thrombin inhibition on the development of crescentic glomerular nephritis is discussed.
Argatroban in Thrombotic Stroke
Authors: LaMonte Marian P.
Published: June 2003

Evidence for the potential use of direct thrombin inhibition in the treatment of acute stroke is reviewed. Reduction of secondary microthrombi and improved regional collateral cerebral blood flow is the proposed mechanism of action of thrombin inhibition for the treatment of cerebral ischemia. A clinical study in Japan found that argatroban administered within 48 h of stroke symptom onset is safe and effective in reducing neurological impairment due to ischemic stroke. The implications of further clinical studies are discussed.
Practical Issues in the Development of Argatroban: A Perspective
Authors: Fareed Jawed , Hoppensteadt Debra , Iqbal Omer , Tobu Mehmut , Lewis Bruce E.
Published: June 2003

Argatroban was the very first antithrombin agent that was approved for clinical use. It represents a synthetic arginomimetic drug with multiple pharmacologic properties. Unlike other antithrombin drugs, argatroban is a reversible antithrombin agent. Furthermore, it modulates endothelial cell function and downregulates various inflammatory and thrombotic cytokines. Argatroban is an effective anticoagulant agent, which at equivalent anticoagulant levels (activated clotting time; ACT) produces a stronger anticoagulant effect in comparison to heparins and hirudins. At a comparable ACT (300 s), argatroban produces much stronger inhibition of thrombin generation as measured by F1.2 and thrombin-antithrombin complex generation. Argatroban does not generate any neutralizing or non-neutralizing antibodies and, therefore, it does not require any dosage adjustment during the course of therapy as other thrombin inhibitors require. The pharmacological profile of argatroban is unique as this antithrombin drug not only inhibits thrombogenesis but also modulates cellular functions. Because of its broad spectral actions, argatroban will have more expanded indications.
Hawk Calls Elicit Alarm and Defensive Reactions in Captive Geoffroy’s Marmosets (Callithrix geoffroyi)
Authors: Searcy Yvonne M. , Caine Nancy G.
Published: June 2003

Most descriptions of callitrichid antipredator behavior have come from observations of visual encounters with predators, but there is also anecdotal evidence suggesting that callitrichids may use auditory cues associated with raptors for the early detection of potential danger. In the present study, Geoffroy’s marmosets consistently reacted to the tape-recorded calls of a red-tailed hawk (Buteo jamaicensis) with high-intensity antipredator behaviors. Compared to the taped calls of a raven (Corvus corax) and the taped sound of a power drill, the hawk calls elicited more startle reactions, more alarm calls, longer freeze times, increased use of safe areas of their enclosure and greater disruption in ongoing behavior. Once in a relatively safe location in the enclosure, the marmosets visually monitored the site of origin of the calls for 10 min and minimized locomotion for 30 min, but resumed baseline levels of other activities that had been disrupted by the hawk calls. Marmosets may use the auditory cues associated with predators for early detection, and subsequent avoidance, of a potential predator in the vicinity.
Das Sein auf der Grenze – wo Berührung und Trennung zusammenkommen1
Authors: Huber Roland
Published: June 2003

Wir kommen kulturgeschichtlich zunehmend in eine Zeit hinein, in der dem Phänomen der Grenze gesellschaftlich wie subjektpsychologisch erhöhte Bedeutung zukommt. In der Archetypologie der Grenze waltet eine Gegensatzdynamik, aus der es kein Entrinnen gibt. Das zeigt sich insbesondere da, wo wir Grenzwirklichkeiten gesellschaftlich, ökonomisch oder humanistisch motiviert reduzieren, aufheben wollen. Insofern verweist die Phänomenologie wie die psychologische Dynamik von Grenze direkt ins Kernland jungianischen Seelen- und Seinsverständnisses: Wirklichkeit ist gegensatzpolar strukturiert. Auch in der psychotherapeutischen Arbeit sind wir heute herausgefordert, Antworten auf menschliches Leiden zu finden, das durch die Grenzphänomenologie des Dissoziablen, Multiplen und Kontradiktorischen geprägt ist.
A Double-Blind Placebo-Controlled Evaluation of Sublingual Immunotherapy with a Standardized Ragweed Extract in Patients with Seasonal Rhinitis
Authors: André C. , Perrin-Fayolle M. , Grosclaude M. , Couturier P. , Basset D. , Cornillon J. , Piperno D. , Girodet B. , Sanchez R. , Vallon C. , Bellier P. , Nasr M.
Published: June 2003

Background: There is a growing consensus on the benefits of sublingual-swallow immunotherapy in the treatment of allergic diseases. Methods: This randomized, double-blind placebo-controlled study was undertaken to assess the efficacy and safety of sublingual immunotherapy with standardized ragweed pollen extract tablets, in patients with an allergic rhinitis. A total of 110 outpatients were randomized (immunotherapy [I]: 55; placebo [P]: 55), of whom 99 were analyzable for efficacy (I: 48; P: 51) and 106 analyzable for safety (I: 53; P: 53). After a 28-day progression phase, the patients received a maintenance treatment during 6.5 months. Efficacy variables included a global assessment of efficacy (patient/ investigator), symptoms and medication scores as well as the frequency of asthma attacks. Results: In the active treatment group, 43 patients completed the study, versus 49 on placebo. During the whole period of pollination, the difference favoring immunotherapy was highly significant for the global assessment by the patient (p = 0.004) and by the investigator (p = 0.005). Adverse reactions were reported more often in the active treatment but mild or moderate, and they abated after dose adjustment. A subgroup analysis of those patients receiving the highest dose of immunotherapy (3 tablets 3 times a week) showed a highly significant response for rhinitis and conjunctivitis total scores by comparison to lower dosages. Conclusion: This study confirms the efficacy and safety of sublingual immunotherapy and strongly suggests a dose-response relationship.
Developmental Aspects of Panic and Related Anxiety Disorders
Authors: Hobbs Jacqueline A. , Shekhar Anantha
Published: June 2003

Panic and related anxiety disorders are common psychiatric disorders. Both genetic and environmental factors appear to contribute to their development. Multiple brain regions including the amygdala, hippocampus, and frontal cortex, as well as associated neurotransmitter and neuroendocrine systems have been implicated in the development of these disorders. Early life stressors such as maternal separation, inflammation, and infection also appear to play important roles. This review will discuss recent animal and human studies that are beginning to elucidate the neurodevelopmental mechanisms of panic and anxiety disorders.
Molecular Plasticity in the Rat Auditory Brainstem: Modulation of Expression and Distribution of Phosphoserine, Phospho-CREB and TrkB after Noise Trauma
Authors: Michler Steffen A. , Illing Robert-Benjamin
Published: June 2003

We induced acoustic trauma by applying click stimuli of 130 dB (SPL) for 30 min to one ear of adult rats. This treatment resulted in an instant and permanent threshold shift of 96 dB in the affected ear. A massive reduction of cochlear nerve fibers in the ventral cochlear nucleus (VCN) was demonstrated by tracing them from the cochlea of rats that survived acoustic overstimulation for 1 year or longer. In the auditory brainstem, we observed a deprivation-dependent appearance of fibers positive for tyrosine receptor kinase B in the ipsilateral VCN between day 3 and day 21 after trauma and an increase in phosphoserine immunostaining in the neuropil of the ipsilateral VCN and in neurons of the contralateral lateral superior olive during the first 30 days after trauma. Immunoreactivity for the cAMP response element binding protein in its phosphorylated form was transiently depressed in the ipsilateral inferior colliculus immediately after trauma and was elevated as late as 7 months after trauma in the ipsilateral VCN. Apparently, a unilateral acoustic overstimulation entails specific regulations of the activity of plasticity-associated molecules through phosphorylation and includes changes to neurotrophin signaling between neurons of the auditory brainstem.
A Paradigm to Measure Mismatch Negativity Responses to Phonetic and Acoustic Changes in Parallel
Authors: Takegata Rika , Mariotto Roggia Simone , Näätänen Risto
Published: June 2003

The mismatch negativity (MMN) of the event-related potential has been purported to be an objective index of central auditory processing. The present study tested a new paradigm to measure the MMN responses to phonological changes in parallel with those to simple acoustic changes. Stimulus sequences consisted of repetitive consonant-vowel syllables interspersed with infrequent phonetic changes (in place of articulation or voicing) and repetitive sinusoidal tones with occasional acoustic changes (in frequency or duration). The speech and tone stimuli were delivered to the opposite ears (right and left, respectively) at a stimulus onset asynchrony (SOA) of 300 ms. The MMNs elicited in this new paradigm were compared with those measured in a conventional paradigm, in which the speech and tone stimuli were presented in separate sequences at an identical speech-speech or tone-tone SOA (600 ms) of the new paradigm. The MMNs elicited in the two paradigms had a similar morphology and topography, although the MMNs measured with the new paradigm were slightly smaller for 3 out of 4 types of deviants. The results suggest that the new paradigm enables the measurement of reliable MMNs to phonetic changes in parallel with those to acoustic changes.
Proliferative Vitreoretinopathy: Cytologic Findings in Vitreous Samples
Authors: Martín Francisco , Pastor J. Carlos , de la Rúa Enrique Rodríguez , Mayo-Iscar Agustín , García-Arumí José , Martínez Vicente , Fernández Nieves , Saornil María A.
Published: June 2003

Purpose: To compare the cellularity of vitreous samples obtained from patients with rhegmatogenous retinal detachment complicated by proliferative vitreoretinopathy (PVR) and from patients with uncomplicated rhegmatogenous retinal detachment (RD) to detect possible variations in cellularity over time. Methods: One hundred and twenty-five vitreous specimens collected from patients with RD (n = 41) and PVR (n = 84) were processed through direct paraffin embedding and cytospin. Different cell types were identified by light-microscopy (hematoxylin-eosin and Papanicolaou stain) according to their morphologic features, and a scale of cellular density was established for each cell type. Student’s t test was used to analyze differences in the cellularity of RD versus PVR. A quadratic model was used to identify variations in the density of each cellular type in the PVR group, based on its evolution time. Results: During the first months after surgery, more macrophages and fibroblast-like cells were observed in the PVR group, but at other times no differences were found. Conclusions: There are some differences in vitreous cellularity in PVR specimens when compared with RD. Especially relevant could be the large number of macrophages in earlier stages and their constant presence over time in PVR samples. The cytology of vitreous samples may shed light on the chronology of PVR cell pathobiology.
Do changes in pulse oximeter oxygen saturation predict equivalent changes in arterial oxygen saturation?
Authors: Perkins Gavin D , McAuley Daniel F , Giles Simon , Routledge Helen , Gao Fang
Published: June 2003

Introduction

This study investigates the relation between changes in pulse oximeter oxygen saturation (SpO2) and changes in arterial oxygen saturation (SaO2) in the critically ill, and the effects of acidosis and anaemia on precision of using pulse oximetry to predict SaO2.

Patients and methods

Forty-one consecutive patients were recruited from a nine-bed general intensive care unit into a 2-month study. Patients with significant jaundice (bilirubin >40 μmol/l) or inadequate pulse oximetry tracing were excluded.

Results

A total of 1085 paired readings demonstrated only moderate correlation (r= 0.606; P < 0.01) between changes in SpO2 and those in SaO2, and the pulse oximeter tended to overestimate actual changes in SaO2. Anaemia increased the degree of positive bias whereas acidosis reduced it. However, the magnitude of these changes was small.

Conclusion

Changes in SpO2 do not reliably predict equivalent changes in SaO2 in the critically ill. Neither anaemia nor acidosis alters the relation between SpO2 and SaO2 to any clinically important extent.
A combined approach for the identification of continuous non‐linear systems
Authors: Voss H. U. , Rust H. , Horbelt W. , Timmer J.
Published: June 2003

The identification of a non‐linear continuous output‐only system from a time series is considered for the case that the functional form of the model is not known beforehand. To estimate both functions and parameters, a combination of non‐parametric modelling based on non‐linear regression and parametric modelling based on a multiple shooting algorithm is proposed. This strategy to determine non‐linear differential equations is exemplified on experimental data from a chaotic circuit where an accurate reconstruction of the observed attractor is obtained. Copyright © 2003 John Wiley & Sons, Ltd.
Evaluation of the cure kinetics of isocyanate reactive hot‐melt adhesives with differential scanning calorimetry
Authors: Cui Yanjun , Hong Ling , Wang Xinling , Tang Xiaozhen
Published: June 2003

The matrix polymer of reactive hot‐melt adhesive (RHMA) is an isocyanate‐terminated urethane prepolymer based on oligoester or oligoether diols and diisocyanates. In this study, we explored wet cure kinetics with both isothermal and nonisothermal differential scanning calorimetry methods. Second‐order autocatalytic models were successfully used to evaluate the cure process of both oligoester‐ and oligoether‐based RHMAs. The autocatalyzation effect did not to depend on the structure of diols but on the reaction nature of the end isocyanates. The apparent energy of the overall cure reaction was 86.54 and 84.46 kJ/mol, respectively, which was based on nonisothermal DSC results. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2708–2713, 2003
Simulation of the scale factor of a ductile fracture of polymer blends and composites on the basis of the specific interphase concept
Authors: Oshmyan V. G. , Shamaev M. Yu. , Timan S. A.
Published: June 2003

The concept of interfacial layers surrounding inclusions in a host polymer is accepted as a basic source of the scale factor in the simulation of the large‐strain deformation and fracture of polymer blends and composites. The essence of the phenomenon is the ductile–brittle transition if the polymer ligament thickness exceeds a critical value, which is determined by the nature of the polymer. Original texture‐sensitive constitutive equations have been applied for the simulation of the polymer large‐strain deformation. Two periodic structural models of composites have been used. The disperse component (elastomeric or rigid inclusion) has been replaced by a geometrically identical system of pores, which coincides with phenomena of elastomeric inclusion rupture in rubber‐toughened plastics and debonding in particulate‐filled composites. The local loss of stability of an elastic deformation is used as a composite fracture criterion. The specific properties of the interphase can be caused by a specific texture and by closeness to a free surface. This specificity is stated in the model by an improved plastic ability compared with that of a bulk polymer. Our simulations show that the percolation of an interfacial polymer provides the brittle–ductile transition. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2771–2777, 2003
Alignment and structural analysis of membrane polypeptides by 15N and 31P solid‐state NMR spectroscopy
Authors: Bechinger Burkhard , Sizun Christina
Published: June 2003

In contrast to solution NMR spectroscopy, where complete or almost complete averaging leads to isotropic values, the anisotropic character of nuclear interactions is apparent in solid‐state NMR spectra. The orientation dependence of chemical shift and dipolar or quadrupolar interactions has been used to obtain dynamic as well as angular information from polypeptides that strongly interact with phospholipid bilayers. This article illustrates the advantageous characteristics of the anisotropic 15N or 31P chemical shift interactions that in a direct manner allow one to obtain information on the alignment of helical polypeptides or of phospholipid head groups with respect to the membrane normal. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson 18A: 130–145, 2003
Recovery from EAE is associated with decreased survival of encephalitogenic T cells in the CNS of B7‐1/B7‐2‐deficient mice
Authors: Chang Tammy T. , Sobel Raymond A. , Wei Tao , Ransohoff Richard M. , Kuchroo Vijay K. , Sharpe Arlene H.
Published: June 2003

Adoptive transfer experiments using C57BL/6 mice lacking B7‐1 and B7‐2 as recipients of wt (wt) encephalitogenic T cells demonstrate a key role for B7 costimulation during the effector phase of experimental autoimmune encephalomyelitis (EAE). Following transfer of encephalitogenic T cells, B7‐1/B7‐2‐deficient (–/–) recipients develop a transient and mild disease as compared to wt recipients. To understand the mechanism by which B7‐1/B7‐2 may influence the effector phase of EAE, we analyzed T cells, pro‐inflammatory cytokines and chemokines within the CNS of wt and B7‐1/B7‐2–/– recipients at different times after adoptive transfer of activated myelin specific T cells. There was a marked decline in T cells and inflammatory mediators in the CNS of B7‐1/B7‐2–/– recipients by day 30 post transfer. B7‐1/B7‐2–/– mice developed more TUNEL+ apoptotic cells in the parenchyma and greater ratios of TUNEL+ cells/parenchymal foci than wt mice resulting in virtual disappearance of parenchymal foci. Therefore, without B7‐1 and B7‐2 costimulation in the target organ, there is increased T cell apoptosis and attenuation of inflammation. Theseresults indicate that B7‐1 and B7‐2 provide critical costimulatory signals for sustaining survival of pathogenic T cells within the central nervous system parenchyma during the effector phase of EAE and suggest novel treatment approaches in the effector phase of autoimmune diseases.
Thymic epithelial cells provide Wnt signals to developing thymocytes
Authors: Pongracz Judit , Hare Katherine , Harman Benjamin , Anderson Graham , Jenkinson Eric J.
Published: June 2003

Interactions with thymic stromal cells are known to be critical for the development of T cells from progenitors entering the thymus, yet the molecular mechanisms of stromal cell function remain poorly understood. Accumulating evidence has highlighted the importance of β‐catenin‐mediated activation of T cell factor (TCF)/lymphoid enhancer factor (LEF) transcription during thymocyte development. As regulation of this signaling pathway is controlled by binding of soluble Wnt proteins to cell surface Frizzled (Fz) receptors, we studied components of Wnt/Fz‐mediated signaling in thecontext of stromal cell regulation of thymocyte development. We show that mRNA for a variety of Wnt family members, notably Wnt‐4, Wnt‐7a and 7b, and Wnt‐10a and 10b, are expressed by thymic epithelium rather then by thymocytes, while thymocytes demonstrate a developmentally regulated pattern of Fz receptor expression. Collectively these findings suggest (1) a functional role for Wnt‐producing thymic epithelium in determining TCF/LEF‐mediated transcriptional regulation in Fz‐bearing thymocytes, and (2) a role for defined Wnt‐Fz interactions at successive stages of thymocyte maturation. In support of this we show that separation of thymocytes from Wnt‐producing epithelial cells and the thymic microenvironment, triggers β‐catenin phosphorylation and degradation in thymocytes. Thus, sustained exposure to Wnt in the context of an intact stromal microenvironment is necessary for stabilization of β‐catenin‐mediated signaling in thymocytes.
The ester‐bonded palmitoyl side chains of Pam3CysSerLys4 lipopeptide account for its powerful adjuvanticity to HLA class I‐restricted CD8+ T lymphocytes
Authors: Reschner Anca , Moretta Antonia , Landmann Regine , Heberer Michael , Spagnoli Giulio C. , Padovan Elisabetta
Published: June 2003

Molecularly defined adjuvants are urgently required to implement immunization protocols by which CD8+ T cells induction is envisaged. We show here that the synthetic lipopeptide Pam3CysSerLys4 (P3CSK4) strongly enhances the expansion of antigen‐specific IFN‐γ+CD8+ cells in vitro. These effects critically depend on the presence of two ester‐bonded palmitoylated side chains. In fact, T cell expansion is impaired in the presence of derivatives bearing two non‐palmitoylated fatty acid chains, while derivatives with only one amide‐bonded palmitoylated residue are completely inactive and behave like the non‐lipidated peptide backbone. P3CSK4 is not mitogenic for T lymphocytes and can modulte DC immune biological properties. Indeed, doses as low as 100 ng/ml increase CD86, CD83 and CD40 surface expression on DC, fail to induce CCR7, and trigger a defined pattern of soluble factors associated to immune effector functions. In particular, substantial amounts of TNF‐α, IL‐6, CCL2 and CXCL10, in the absence of IFN‐α, IFN‐γ, IL‐15, IL‐12p70 and CX3CL1, can be measured. Accordingly, antigen‐specific CD8+ T cells expanded in vitro express CCR2 and CXCR3 chemokine receptors. Altogether our data suggest that human DC are able to respond to chemically different synthetic lipopeptide analogs and that optimal adjuvanticity to CD8+ T cell induction is achieved by the palmitoylated structures.
Incomplete effector/memory differentiation of antigen‐primed CD8+ T cells in gene gun DNA‐vaccinated mice
Authors: Bartholdy Christina , Stryhn Anette , Hansen Nils Jakob Vest , Buus Søren , Thomsen Allan Randrup
Published: June 2003

DNA vaccination is an efficient way to induce CD8+ T cell memory, but it is still unclear to what extent such memory responses afford protection in vivo. To study this, we induced CD8+ memory responses directed towards defined viral epitopes, using DNA vaccines encoding immunodominant MHC class I‐restricted epitopes of lymphocytic choriomeningitis virus covalently linked to β2‐microglobulin. This vaccine construct primed for a stronger recall response than did a more conventional minigene construct. Despite this, vaccinated mice were only protected against systemic infection whereas protection against the consequences of peripheral challenge was limited. Phenotypic analysis revealed that DNA vaccine‐primed CD8+ T cells in uninfected mice differed from virus‐primed CD8+ T cells particularly regarding expression of very‐late antigen (VLA)‐4, an adhesion molecule important for targeting T cells to inflammatory sites. Thus, our DNA vaccine induces a long‐lived memory CD8+ T cell population that provides efficient protection against high‐dose systemic infection. However, viral replication in solid non‐lymphoid organs is not curtailed sufficiently fast to prevent significant virus‐induced inflammation. Our results suggest that this is due to qualitative limitations of the primed CD8+ T cells.
Correction: Disease in the scurfy (sf) mouse is associated with overexpression of cytokine genesDisease in the scurfy (sf) mouse is associated with overexpression of cytokine genes (Eur. J. Immunol. 7/2003)
Authors: Kanangat S. , Blair P. , Reddy R. , Daheshia M. , Godrey V. , Rouse B. T. , Wilkinson E.
Published: June 2003

Vol. 26(1) 1996, pp 161‐165

In this article, the name of Massoud Daheshia was unfortunately published incorrectly: the correct spelling is as given here.
Processes and mechanisms of dynamic channel adjustment to delta progradation: the case of the mouth channel of the Yellow River, China
Authors: Shi Changxing , Zhang Dian
Published: June 2003

This paper analyses the processes and mechanisms of a three‐stage channel adjustment over a cycle of the Yellow River mouth channel extension based on data comprising hydrologic measurements and channel geometric surveys. Rapid siltation in the mouth channel takes place in the young stage when the channel is being built by deposits and in the old stage when the channel cannot further adjust itself to keep sediment transport in equilibrium. It is disclosed that the bankfull width–depth ratio, bed material size and slope decrease in the young and mature stages but do not change in the old stage. The reduction of bankfull width–depth ratio and bed material size during the young and mature stages is found to be able to offset the effect of the slope reduction on sediment transport due to continuous mouth progradation. They reach their limits in old stage, and a constant slope is kept by unceasing sediment accumulation. The grain size composition of incoming sediment and the fining mechanism are responsible for the occurrence of lower limit of bed material size. The reason for the existence of a limit of bankfull cross‐sectional shape is that the large flows can fully transport the sediment load they are carrying, and siltation in the channel in the old stage takes place mainly in the low flows. It is suggested that the bankfull discharge plays an important role in shaping the channel but that the entire channel form is the product of both the large and low flows plus the effects of interaction between them. Channel pattern change shows a process from a braided pattern in the young stage to a straight pattern in the mature and old stages, and the straight channel becomes gradually sinuous. The occurrence and transformation of the channel patterns are supported by two planform predictors, but are also facilitated by some other conditions. Copyright © 2003 John Wiley & Sons, Ltd.
Contribution of the rev gene to the immunogenicity of DNA vaccines targeting the envelope glycoprotein of HIV
Authors: Jounai Nao , Okuda Kenji , Kojima Yoshitsugu , Toda Yoshihiko , Hamajima Kenji , Ohba Kenji , Klinman Dennis , Xin Ke‐Qin
Published: June 2003

Background

The Rev protein of HIV plays a critical role in the export of viral mRNA from the nucleus to the cytoplasm of infected cells. This work examines the effect of introducing rev into a DNA vaccine encoding the Env protein of HIV, and compares the activity of env genes regulated by CMV versus CAG promoters.

Methods

The HIV Env gp160 encoding gene with or without the rev gene was subcloned into a CMV promoter or a CAG promoter‐driven expression plasmid. The Env protein expression of the plasmids was examined in vitro and the HIV‐specific immunity was explored in BALB/c mice by an intramuscular route. The immune mice were intraperitoneally challenged with an HIV Env‐expression vaccinia virus.

Results

Results indicate that the CAG promoter induces significantly higher levels of Env expression, and better immune responses, than the CMV promoter. Incorporating the rev gene into these plasmids further boosts antigen expression and immunogenicity. Indeed, vaccination with the pCAGrev/env or pCMVrev/env plasmid resulted in 1000‐fold lower viral load than that with pCMVenv when the mice were challenged with an Env‐expressing vaccinia virus.

Conclusions

Incorporating rev into a DNA vaccine significantly increases the level of expression and immunogenicity of a co‐expressed env gene, and that protective efficacy is further improved by utilizing a pCAG promoter. Copyright © 2003 John Wiley & Sons, Ltd.
V centres in plastically deformed SrS
Authors: Seeman V. , Danilkin M. , Must M. , Ots A. , Pung L.
Published: June 2003

V centres of several types were studied by electron paramagnetic resonance in SrS polycrystals for the first time. Both isolated cation vacancies and their complexes with other defects are formed in SrS during plastic deformation and are further transformed by ionic processes on annealing. They become paramagnetic when the samples are irradiated by X‐rays at 77 K and a hole is captured by a S2– ion situated next to a cation vacancy. Thus, V– centres arise from isolated cation vacancies vc, VSH from vc – (SH)– complexes, and V2(SH)+ from (SH)– – vc – (SH)– complexes. The holes captured are released from V centres below room temperature, within a very wide temperature range. The electric fields of dislocations are supposed to modify the activation energies of hole release. Low activation temperatures of ionic processes (compared with ionic conductivity of undamaged SrS) indicate that defects are transported by dislocations in plastically deformed SrS.
Piezoelectric properties of GPI crystals
Authors: Wiesner Maciej
Published: June 2003

It is found that the piezoelectric properties of glycine phosphite (GPI) were preserved up to 264 K, which contradicts the presence of a symmetry centre phase above TC. The resonance frequency jump at the phase transition was ∼0.15%, which is more than ten times smaller when compared to the sound velocity jump. In order to explain such persistent behaviour of the sample, a complementary measurement of the spontaneous polarisation Ps was made. Not only was Ps observed up to 270 K, but two kinds of polarisation were distinguished: the first disappeared at ∼226 K, and the second was present up to 270 K.
An appraisal of the crystal field in rare earth intermetallics: TmCu2Si2
Authors: Chatterji A. , Chatterjee S. , Chatterjee Reba
Published: June 2003

A crystal field (CF) investigation of the properties of Tm3+ in TmCu2Si2 has been done for an appraisal of the CF proposed by Kosaka et al. [J. Phys. Soc. Jpn. 66, 2844 (1997)] from their magnetic studies and inelastic neutron scattering investigation. As these CF parameters were found to give only a qualitative explanation of the observed data, they were refined to have a closer fit to the observed magnetic susceptibility, Stark levels obtained from inelastic neutron scattering studies, and thermal variation of nuclear electric quadrupole splitting. It has been found that molecular field interactions play a dominant role at low temperatures. Other properties investigated theoretically with the help of the refined set of CF parameters are amenable to experimental check.
A practical approach to steam‐enhanced dual‐phase extraction: A case study
Authors: Bouchard David P. , Musterait Todd M. , Sobieraj James A.
Published: June 2003

This article presents the results of a pilot test that was conducted to determine the effectiveness of using
steam‐enhanced dual‐phase extraction (DPE) at a former industrial site in New York. The
pilot test proved that steam‐enhanced DPE was very effective at removing significant contaminant mass
from the subsurface in a relatively short time period. Concentrations of volatile organic compounds and
semivolatile organic compounds in the vapor stream and groundwater were successfully reduced, in some cases by
orders of magnitude. Based on the results of the steam‐enhanced DPE pilot test, the final remedy for the
site includes implementing this technology at selected areas as an alternative to DPE alone or other remedial
alternatives, such as excavation or groundwater pump and treat. © 2003 Wiley Periodicals, Inc.
Field trial experiment: Phytoremediation with Salix sp. on a dredged sediment disposal site in Flanders, Belgium
Authors: Meers Erik , Vervaeke Pieter , Tack Filip M.G. , Lust Noel , Verloo Marc , Lesage Els
Published: June 2003

Remediation of heavy metal contamination in soil is a widespread environmental issue. Conventional
remediation techniques are invasive and often too expensive, particularly if large areas of soil are
contaminated. Phytoremediation is the use of plants to remediate soil and groundwater. Phytoremediation of
inorganic comtaminants such as metals can be further catagorized into phytostabilization and phytoextraction.
These techniques have gained an increasing amount of attention and research over the last ten years.
Phytoextraction of heavy metals and periodical removal of harvestable plant parts results in a gradual decrease
of pollutant levels in the top soil. Woody species such as Salix sp. (willow) do not
represent the fastest phytoextraction procedure compared to uptake by herbaceous species; however, they
offer the added advantage of possible reuse of the produced biomass (wood) for the production of
renewable energy. Here we present the results of a field experiment conducted to evaluate the use of
Salix to remediate soil contaminated with cadmium and zinc at a dredged sediment disposal site
in Flanders, Belgium. © 2003 Wiley Periodicals, Inc.
Survey of recently board‐certified prosthodontists on the board certification process. part 1: Demographics
Authors: Rashedi Behnoush , Abt Joy Bockstein , Petropoulos Vicki C.
Published: June 2003

Purpose A survey of recently board‐certified prosthodontists was conducted in 2001. The purpose of this survey was to identify trends that assisted candidates in attaining diplomate status.

Materials and Methods A questionnaire was mailed to 176 diplomates who had become board certified between the years 1993 and 2001. Of these, 131 board‐certified prosthodontists returned the completed survey, resulting in a response rate of 74%. The mean, median, and range of responses were computed when applicable.

Results Results from this survey show that the mean number of years from completion of a postdoctoral program to achieving board certification was 6 years, with a median of 4 years and a range of 1 to 23 years. The mean number of years from the time of completion of a postdoctoral program to board eligibility was 2.3 years, with a median of 1 year and a range of 0 to 22 years. The mean number of years from board eligibility to board certification was 3.9 years, with a median of 3 years and a range of 0 to 17 years. The military was the most frequently reported employment status at the time the respondents took Parts 1–4 of the boards. A total of 54% of the diplomates reported that they challenged Part 1 separately, and then challenged Parts 2, 3, and 4 together; 79% of the diplomates were encouraged by their graduate program director/faculty to challenge the board; and 48% of the diplomates reported that their patients received free dental treatment.

Conclusions Certain trends were observed regarding diplomates who succeeded in their efforts to challenge the board examination. The largest group who challenged the board certification examinations comprised members of the armed forces. Most prosthodontists challenged Part 1 before challenging the remaining 3 parts. In an effort to encourage more prosthodontists to challenge the board examination, numerous changes were made between 1992 and 1998; however, most of the diplomates did not take advantage of those changes.
Ground vs. surface air temperature trends: Implications for borehole surface temperature reconstructions
Authors: Mann Michael E. , Schmidt Gavin A.
Published: June 2003

We have analyzed the relationship between surface air temperature (SAT), ground surface temperature (GST), and snow cover (SNC) over the terrestrial Northern Hemisphere based on general circulation model (GCM) simulations using GISS modelE forced with the observed SST and radiative forcing changes from 1951–1998. While SAT is the dominant influence on GST during the warm‐season, it explains only half of the variance in GST during the cold‐season, with SNC and pre‐conditioning by prior warm‐season SAT also exhibiting a sizeable and, in places, dominant influence. During a period of coincident surface warming and cold‐season snowcover decrease in the model (1971–1998), mean GST increases are 0.2°C less than those in SAT, a consequence of greater exposure of the ground surface to winter cold air outbreaks. Interpretations of past SAT trends from borehole‐based GST reconstructions may therefore be substantially biased by seasonal influences and snow cover changes.
C4d deposition in peritubular capillary and alloantibody in the allografted kidney suffering severe acute rejection
Authors: Abe Masahiro , Sawada Tokihiko , Horita Shigeru , Toma Hiroshi , Yamaguchi Yutaka , Teraoka Satoshi
Published: June 2003

Abstract:  Background: Alloantibodies and C4d deposition in peritubular capillaries (PTCs) are thought to be related to antibody‐mediated acute rejection. The purpose of this study was to evaluate the relationship between C4d deposition in PTCs and alloantibodies at various days after allograft dysfunction due to severe acute rejection. Method: There were 620 renal transplantations (Tx) performed. Forty patients diagnosed with acute humoral and/or vascular rejection showed graft dysfunction with anuria or dysuria. The patients were divided into four groups by ABO compatibility and clinical course after graft dysfunction: compatible recipients with graft loss (c‐GL; n = 6); compatible recipients with recovery from graft dysfunction (c‐RE; n = 10); incompatible recipients with graft loss (i‐GL; n = 9); and incompatible recipients with recovery from graft dysfunction (i‐RE; n = 15). Results: C4d depositions in 4/6 c‐GL recipients increased, and those in 8/10 c‐RE recipients decreased after graft dysfunction. These changes in C4d deposition between the c‐GL and the c‐RE groups were significantly different (P < 0.01). These titres of anti‐A/B IgG antibody in 7/9 i‐GL recipients increased and those in 8/15 i‐RE recipients decreased after graft dysfunction. These changes in titre between the i‐GL and the i‐RE groups were significantly different (P < 0.01). All c‐GL recipients and 4/10 c‐RE recipients had anti‐HLA antibody at the last biopsy. There was a significant difference in the number of recipients who had anti‐HLA antibody between the c‐GL and the c‐RE groups (P < 0.05). Conclusions: These results indicate that changes in C4d deposition in PTCs in the c‐ABO group and titre of anti‐A/B IgG antibody in the ABO‐incompatible groups exert a strong impact on graft survival after dysfunction in the early period after Tx.
Hyperosmolarity decreases the relaxing potency of sodium nitroprusside on guinea‐pig trachea by the release of superoxide anions
Authors: Hjoberg J. , Högman M. , Hedenstierna G.
Published: June 2003

Increased osmolarity of the airway surface has been shown to abolish the airway relaxant effects of inhaled nitric oxide in rabbits in vivo and in guinea‐pig trachea in vitro.

Aim:  In this study, we used a guinea‐pig tracheal perfusion method to investigate whether superoxide anions, which rapidly react with nitric oxide, could be responsible for the reduced effect of nitric oxide in hyperosmolar airways.

Methods:  Guinea‐pig tracheas were constricted with carbachol (CCh) and then subjected to the nitric oxide donor sodium nitroprusside (SNP) under isoosmolar or hyperosmolar conditions. Hyperosmolarity was created by increasing the NaCl concentration of the buffer on the epithelial side of the airway.

Results:  The relaxation produced by SNP was significantly less following hyperosmolar challenge, with a relaxation by 31 ± 7% in hyperosmolar conditions as compared to 53 ± 6% under normal isoosmolar conditions (P < 0.05). The experiment was then performed in the presence of superoxide dismutase (SOD) that reduces levels of superoxide anions. SOD restored the relaxing potency of SNP in hyperosmolar conditions back to normal, to 46 ± 5%.

Conclusion:  This study shows that superoxide anions are responsible for the reduced relaxing potency of the nitric oxide donor SNP following an intraluminal hyperosmolar challenge in guinea‐pig trachea in vitro. The finding may form the basis for new treatment of patients not responding to treatment with inhaled nitric oxide.
The efficacy of omeprazole twice daily with supplemental H2 blockade at bedtime in the suppression of nocturnal oesophageal and gastric acidity
Authors: Orr W. C. , Harnish M. J.
Published: June 2003

Background: It has been presumed that nocturnal acid breakthrough may pose a risk for the development of nocturnal gastro‐oesophageal reflux.

Aim: To investigate the occurrence of gastro‐oesophageal reflux and acid breakthrough during polygraphically monitored sleep under conditions of powerful acid suppression with omeprazole 20 mg b.d. and an additional dose of ranitidine at bedtime.

Methods: Nineteen individuals with symptomatic gastro‐oesophageal reflux disease were studied. Each individual was studied on two occasions subsequent to 1 week of 20 mg of omeprazole treatment b.d. Subjects underwent 24‐h oesophageal and gastric pH recording, with polysomnographic monitoring. Participants received either 150 mg ranitidine at bedtime or placebo, prior to a provocative meal.

Results: Ranitidine administration resulted in a significant (P < 0.01) reduction in the percentage of time the intragastric pH < 4.0. There was no significant difference with regard to measures of gastro‐oesophageal reflux, and reflux events were not noted to occur with a significantly greater frequency during periods of nocturnal acid breakthrough compared with control intervals without acid breakthrough.

Conclusions: The administration of 150 mg ranitidine at bedtime did not significantly alter the occurrence of sleep‐related gastro‐oesophageal reflux.