julilili42/papers huggingface dataset:
Aleukemic Mast Cell Leukemia with Abnormal Immunophenotype and C-kit Mutation D816V
2004-07-16

Mastocytosis comprises a heterogeneous group of disorders characterized by proliferation and accumulation of mast cells in 1 or more organ systems. Mast cell leukemia (MCL) is an extremely rare subtype of mastocytosis in which a leukemic spread of mast cells and a rapid progression of disease is seen. In typical cases, mast cells are found in the peripheral blood. However, an aleukemic variant of MCL (formerly termed malignant mastocytosis) has also been described. We here report a case of aleukemic MCL with abnormal immunophenotype of mast cells and the classical c-kit point mutation Asp-816-Val (=D816V). The 75-year-old male patient had a short history of weight loss and lymphadenopathy. There were no urticaria pigmentosa-like skin lesions. The bone marrow was diffusely infiltrated with atypical mast cells that comprised more than 80% of all nucleated cells on a bone marrow smears. As assessed by immunohistochemistry, neoplastic mast cells expressed tryptase, chymase, CD2, CD25, CD68, and the KIT protein (CD117). Mutation analysis revealed the c-kit mutation D816V. Since circulating mast cells could not be detected in the peripheral blood, the diagnosis of aleukemic MCL was established in accordance to the updated WHO consensus classification. This case further supports the notion that the pathogenesis (c-kit mutation D816V) in MCL is closely related to that found in indolent mast cell disorders. However, additional (but yet unknown) molecular (genetic) defects have to be considered to explain the extremely heterogenous clinical course in these patients.
Influence of somatosensory input on motor function in patients with chronic stroke
2004-07-19

Abstract In healthy volunteers, reduction of somatosensory input from one hand leads to rapid performance improvements in the other hand. Thus, it is possible that reduction of somatosensory input from the healthy hand can influence motor function in the paretic hand of chronic stroke patients with unilateral hand weakness. To test this hypothesis, we had 13 chronic stroke patients perform motor tasks with the paretic hand and arm during cutaneous anesthesia of the healthy hand and healthy foot in separate sessions. Performance of a finger tapping task, but not a wrist flexion task, improved significantly with anesthesia of the hand, but not the foot. This effect progressed with the duration of anesthesia and correlated with baseline motor function. We conclude that cutaneous anesthesia of the healthy hand elicits transient site‐specific improvements in motor performance of the moderately paretic hand in patients with chronic stroke, consistent with interhemispheric competition models of sensorimotor processing. Ann Neurol 2004;56:206–212
Theoretical Characterization and Design of End‐Substituted Distyrylbenzenes as Excitation Shuttles in One‐Dimensional Channels
2004-07-19

Quantum-chemical calculations have been performed to characterize the potentiality of recently synthesized end-substituted oligophenylenevinylenes (OPVs) as excitation shuttles and to design more efficient derivatives. The approach provides quantitative estimates of the parameters controlling the exciton transfer rates and strategies to promote directional energy transfer.
Ethical Implications of Pharmacogenetics – Do Slippery Slope Arguments Matter?
2004-07-19

ABSTRACT Pharmacogenetics is a rapidly expanding area of research exploring the relationship between inter‐individual genetic variation and drug response, with the goal of developing genetically optimised therapies. Slippery slope arguments claim that a particular action should be rejected (or supported) because it might be the first step onto a slippery slope leading to undesirable (or desirable) consequences. In this article, several slippery slope arguments relevant to the context of pharmacogenetics are evaluated under consideration of underlying reasons for their popularity. The author concludes that although the examined arguments are unconvincing as slippery slope arguments, they do matter in this context. While positive slippery slope arguments serve as a driving force to fuel the development of pharmacogenetics, their negative counterparts play an important role to sensitise policy makers and the public to potential problems.
Synthesis of embedded systemC design: a case study of digital neural networks
2004-07-20

This work presents the whole system-on-silicon design flow using systemC system specification language. In this study, systemC is used to design a multilayer perceptron neural network, which is applied to an electrocardiogram pattern recognition system. The objective of this work is to exemplify the synthesis of RTL-and behavioral integrated systems. To achieve this, a preprocessing methodology was used to optimize the three main constraints of hardware neural network (HNN) design: accuracy, space and processing speed. This allows a complex HNN to be implemented on a single field programmable gate array (FPGA). The high level systemC synthesis allows the straightforward translation of system level into hardware level, avoiding the error prone and the time consuming translation into another hardware description language.
Verification of a microcontroller IP core for system-on-a-chip designs using low-cost prototyping environments
2004-07-20

Rapid prototyping is a fast and efficient way for the functional verification of systems-on-a-chip in an early stage of the design process. Because of the rising part of software in those systems the use and reuse of microcontroller IP cores is necessary to keep development cycles short. Today, prototyping of such IP cores is done with large and expensive hardware emulation machines consisting of many processor or FPGA-based prototyping boards. In this paper the authors describe an alternative prototyping method for microcontrollers using one low-cost FPGA-based prototyping board. The method is based on the efficient usage of all resources of the prototyping system to emulate special parts of the microcontroller.
Interface effects in superconductor–carbon nanotube hybrid structures
2004-07-20

The objective of the present paper is to investigate the proximity effect in\\njunctions of superconductors with carbon nanotubes. The method is the lattice\\nBdG equations within the Hubbard model. The proximity effect depends\\nsensitively on the connection giving the possibility to control the proximity\\neffect by performing simple geometrical changes in the hybrid system\\n
Oral anticoagulant treatment: friend or foe in cardiovascular disease?
2004-07-21

Abstract Calcification is a common complication in cardiovascular disease and may affect both arteries and heart valves. Matrix γ-carboxyglutamic acid (Gla) protein (MGP) is a potent inhibitor of vascular calcification, the activity of which is regulated by vitamin K. In animal models, vitamin K antagonists (oral anticoagulants [OACs]) were shown to induce arterial calcification. To investigate whether long-term OAC treatment may induce calcification in humans also, we have measured the grade of aortic valve calcification in patients with and without preoperative OAC treatment. OAC-treated subjects were matched with nontreated ones for age, sex, and disease. Calcifications in patients receiving preoperative OAC treatment were significantly (2-fold) larger than in nontreated patients. These observations suggest that OACs, which are widely used for antithrombotic therapy, may induce cardiovascular calcifications as an adverse side effect.
Motor Skill Learning Depends on Protein Synthesis in Motor Cortex after Training
2004-07-21

The role of protein synthesis in memory consolidation is well established for hippocampus-dependent learning and synaptic plasticity. Whether protein synthesis is required for motor skill learning is unknown. We hypothesized that skill learning is interrupted by protein synthesis inhibition (PSI). We intended to test whether local protein synthesis in motor cortex or cerebellum is required during skill acquisition and consolidation. Anisomycin (ANI; 100 μg/μl in 1 μl of PBS) injected into motor cortex, posterior parietal cortex, or cerebellum produced 84.0 ± 1.44% (mean ± SEM), 85.9 ± 2.31%, and 87.3 ± 0.17% of PSI 60 min after administration, respectively. In motor cortex, protein synthesis was still reduced at 24 hr (72.0 ± 4.68% PSI) but normalized at 48 hr after a second injection given 24 hr after the first. To test for the effects of PSI on learning of a skilled reaching task, ANI was injected into motor cortex contralateral to the trained limb or into ipsilateral cerebellum immediately after daily training sessions 1 and 2. Two control groups received motor cortex injections of vehicle or ANI injections into contralateral parietal cortex. Control and cerebellar animals showed a sigmoid learning curve, which plateaued after day 4. PSI in motor cortex significantly reduced learning during days 1-4. Thereafter, when protein synthesis normalized, learning was reinitiated. ANI injections into motor cortex did not induce a motor deficit, because animals injected during the performance plateau did not deteriorate. This demonstrates that motor skill learning depends on de novo synthesis of proteins in motor cortex after training.
The impact of ectomycorrhiza formation on monosaccharide transporter gene expression in poplar roots
2004-07-22

• By using degenerate primers, five putative poplar monosaccharide transporter genes were isolated from ectomycorrhizas by RT-PCR. The expression profiles of the three most strongly expressed ones are presented in detail. • Two transporter genes (PttMST1.2 and PttMST2.2) were down-regulated by ectomycorrhiza formation. However, PttMST3.1, which showed 10-times higher expression rates in noninfected roots than any other transporter gene, was up-regulated 12-fold in mycorrhizas. • While changes in PttMST1.2 and PttMST2.2 expression might be regulated by a fungal metabolite present in axenically grown hyphae, the strong increase of PttMST3.1 expression in mycorrhizas required active plant-fungus interaction. • Up-regulation of PttMST3.1 by mycorrhiza formation suggests that root cells are able to compete with fungal hyphae for hexoses from the common apoplast during symbiosis, redirecting the sugar-flux back into plant cells whenever the fungal partner does not supply sufficient mineral nutrients. Such a mechanism would enable the plant to link nutrient supply and fungal carbon support at a local level.
Automatic Layout of UML Class Diagrams in Orthogonal Style
2004-07-22

Unified modelling language (UML) diagrams have become increasingly important in engineering and re-engineering processes for software systems. Of particular interest are UML class diagrams whose purpose is to display generalizations, associations, aggregations, and compositions in one picture. The combination of directed and undirected relations poses a special challenge to a graph layout tool. Current approaches for the automatic layout of class diagrams are based on the layered graph drawing paradigm. These algorithms produce good results for class diagrams with large and deep structural information, that is, diagrams with a large and deep inheritance hierarchy. However, they do not perform satisfactorily in absence of this information. We suggest to use the topology-shape—metrics paradigm for automatic layout of class diagrams, which has been used very successfully for drawing undirected graphs in orthogonal style. Moreover, we introduce the algorithms UML-Kandinsky and GoVisual fitting into this paradigm. Both algorithms work for class diagrams with rich structural information as well as for class diagrams with few or no structural information. Therefore, they improve the existing algorithms significantly.
Elevated Nitric Oxide Production in Children with Malarial Anemia: Hemozoin-Induced Nitric Oxide Synthase Type 2 Transcripts and Nitric Oxide in Blood Mononuclear Cells
2004-07-23

ABSTRACT Experiments outlined here investigate the role of nitric oxide (NO) in the pathogenesis of Plasmodium falciparum -induced malarial anemia (MA). The results show that ex vivo and in vitro NO synthase (NOS) activity in peripheral blood mononuclear cells (PBMCs) is significantly elevated in children with MA and inversely associated with hemoglobin levels. Additional experiments using PBMCs from non-malaria-exposed donors demonstrate that physiologic amounts of P. falciparum -derived hemozoin augment NOS type 2 (NOS2) transcripts and NO production. Results of these experiments illustrate that elevated NO production in children with MA is associated with decreased hemoglobin concentrations and that hemozoin can induce NOS2-derived NO formation in cultured blood mononuclear cells.
Development of granulomatous common variable immunodeficiency subsequent to infection withToxoplasma gondii
2004-07-23

SUMMARY Common variable immunodeficiency (CVID) is a heterogeneous immunodeficiency that is accompanied by granulomatous lesions in 5–10% of cases. Why some patients develop granulomatous disease remains unclear. Here we describe a 12-year-old previously healthy girl who presented with pancytopenia and granulomatous lymphoproliferation subsequent to infection with Toxoplasma gondii. Loosely arranged non-fibrosing granulomas were observed in the liver, lymph nodes and lung, but no Toxoplasma tachyzoites could be demonstrated and polymerase chain reaction (PCR) and culture were negative for Toxoplasma and a wide range of other pathogens. While the patient had a normal peripheral B cell status at presentation, the development of CVID could be observed during the following months, leading to a loss of memory B cells. This was accompanied by an increasingly activated CD4+ T cell compartment and high serum levels of angiotensin-converting enzyme (ACE), tumour necrosis factor (TNF) and sCD25. Steroid therapy reduced pancytopenia, granulomatous lymphoproliferation and cytokine elevations, but did not improve the B cell status. This is the first report of an association of Toxoplasma infection with granulomatous CVID and provides one of the rare examples where the onset of CVID could be documented subsequent to an infectious disease.
Plasmodium Induces Swelling-activated ClC-2 Anion Channels in the Host Erythrocyte
2004-07-24

Intraerythrocytic growth of the human malaria parasite Plasmodium falciparum depends on delivery of nutrients. Moreover, infection challenges cell volume constancy of the host erythrocyte requiring enhanced activity of cell volume regulatory mechanisms. Patch clamp recording demonstrated inwardly and outwardly rectifying anion channels in infected but not in control erythrocytes. The molecular identity of those channels remained elusive. We show here for one channel type that voltage dependence, cell volume sensitivity, and activation by oxidation are identical to ClC-2. Moreover, Western blots and FACS analysis showed protein and functional ClC-2 expression in human erythrocytes and erythrocytes from wild type (Clcn2(+/+)) but not from Clcn2(-/-) mice. Finally, patch clamp recording revealed activation of volume-sensitive inwardly rectifying channels in Plasmodium berghei-infected Clcn2(+/+) but not Clcn2(-/-) erythrocytes. Erythrocytes from infected mice of both genotypes differed in cell volume and inhibition of ClC-2 by ZnCl(2) (1 mm) induced an increase of cell volume only in parasitized Clcn2(+/+) erythrocytes. Lack of ClC-2 did not inhibit P. berghei development in vivo nor substantially affect the mortality of infected mice. In conclusion, activation of host ClC-2 channels participates in the altered permeability of Plasmodium-infected erythrocytes but is not required for intraerythrocytic parasite survival.
Prey snapping and visual distance estimation in Texas horned lizards, Phrynosoma cornutum
2004-07-26

SUMMARY Captive Texas horned lizards were high-speed videotaped while feeding on ants in order to study the role of vision in facilitating tongue-protrusion capture of prey. Analysis of tongue movements revealed that prey snapping in these lizards is not a typical fixed-action pattern. By contrast, it is variable in performance and duration. Lizards adjusted head and tongue direction during the strike, within a few milliseconds, in response to movements of the prey. The duration of a typical tongue strike was 100-150 ms. The strike duration was prolonged after ophthalmic lenses were placed in front of one or both eyes. These lenses were used to investigate whether horned lizards use accommodation to judge prey distance. Focal changes of negatively powered ophthalmic lenses (employed monocularly) induced a clear underestimation of prey distance by the lizards, confirming the hypothesized expectation that accommodation is used for depth perception. The effect of the lenses was different in the two animals tested with monocular restriction. This, together with the lack of difference in responses by the lizards when untreated and when both eyes were lens covered (binocular treatment of equal power, -9 D), illustrates that horned lizards also use other visual parameters for depth perception.
Glycogen phosphorylase isozyme pattern in mammalian retinal Müller (glial) cells and in astrocytes of retina and optic nerve
2004-07-27

Abstract Müller cells, the radially oriented dominant macroglial cells of the retina, are known to contain abundant glycogen as well as the key enzyme for its degradation, glycogen phosphorylase (GP), but the expressed isozyme pattern is unknown. To elucidate the isoform expression pattern, specific antisera directed against the brain (BB) and muscle (MM) isoforms of GP were applied to retinal sections, isolated Müller cells, and sections of the optic nerve. We show that Müller cells of rat, rabbit, guinea pig, and mouse retina exclusively express the BB isoform. Astrocytes of rat and rabbit optic nerve, as well as retina express only the BB isoform. In contrast, astrocytes in the brain and spinal cord as well as the epithelial cells of the pars caeca and of the ciliary body express both the BB and MM isoform. This result may indicate some differences in the role of glycogen in retinal macroglia and brain astrocytes, reflecting a local specialization of macroglia in the retina proper. © 2004 Wiley‐Liss, Inc.
Temporary Intermaxillary Fixation using Individualized Acrylic Splints Permits Image–Data‐Based Surgery of the Lower Jaw and Oropharynx
2004-07-27

Abstract Objectives/Hypothesis: Image–data‐based surgical navigation is used as a helpful device in the operating room to localize critical structures with a high degree of accuracy. It also enables physicians to plan therapeutic performance. Because it relies on preoperatively acquired computed tomography (CT) or magnetic resonance imaging (MRI) data, there is restricted access for navigation of surgical instruments in areas that show motion uncorrelated with radiologic data. Thus, in the case of moveable structures, for example the lower jaw, navigational procedures could not yet be applied. Study Design: We introduce a new technique using individualized intermaxillary splints that fix the mandible in a reproducible aboccluded position at the time of image‐data acquisition and surgery. Methods: Different manufacturing processes were investigated. The feasibility of uni‐ and bilateral intermaxillary splints was studied under clinical conditions in four patients during different procedures in the mandibular and oropharyngeal regions. Results: The manufacturing of the splints showed was easily performed in a short time. With bilateral fixation, there was a high anatomic target precision of 1.6 to 2.3 mm. Conclusions: The use of bilateral intermaxillary splints that fix the patient's mandible in a reproducible aboccluded position permits an image–data‐based navigated surgical approach to the oropharyngeal and mandibular regions.
Neurodegeneration
2004-07-27

This chapter contains sections titled: What Is Neuroprotection? Outcome Measures in Clinical Studies Specific Diseases Wilson's Disease Parkinson's Disease DATATOP Study Dopamine Agonists Anti-Excitotoxic Treatment Neurotrophins MAP Kinase Inhibitors Transplantation Deep Brain Stimulation Coenzyme Q10 Multiple System Atrophy and Progressive Supranuclear Palsy Alzheimer's Disease Symptomatic Treatment Antioxidants Anti-inflammatory Approaches Estrogen Replacement NMDA Receptor Antagonists Experimental Therapies Immunization Cholesterol-lowering Therapy Huntington's Disease Why Do So Many Clinical Studies Fail? What Do We Need? References
Optimal Detection of a Change Point in a Poisson Process for Different Observation Schemes
2004-07-28

Abstract. Change point problems are considered where at some unobservable time the intensity of a point process ( T n ), n ∈ N, has a jump. For a given reward functional we detect the change point optimally for different information schemes. These schemes differ in the available information. We consider three information levels, namely sequential observation of ( T n ), ex post decision after observing the point process up to a fixed time t * and a combination of both observation schemes. In all of these cases the detection problem is viewed as an optimal stopping problem which can be solved by deriving a semimartingale representation of the gain process and applying tools from filtering theory.
Analytic properties of the Landau gauge gluon and quark propagators
2004-07-29

We explore the analytic structure of the gluon and quark propagators of Landau gauge QCD from numerical solutions of the coupled system of renormalized Dyson--Schwinger equations and from fits to lattice data. We find sizable negative norm contributions in the transverse gluon propagator indicating the absence of the transverse gluon from the physical spectrum. A simple analytic structure for the gluon propagator is proposed. For the quark propagator we find evidence for a mass-like singularity on the real timelike momentum axis, with a mass of 350 to 500 MeV. Within the employed Green's functions approach we identify a crucial term in the quark-gluon vertex that leads to a positive definite Schwinger function for the quark propagator.
Medium Modifications of Kaons in Pion Matter
2004-07-29

Kaon in-medium masses and mean-field potentials are calculated in isotopically symmetric pion matter to one loop of chiral perturbation theory. The results are extended to BNL RHIC temperatures using experimental data on piK scattering phase shifts. The kaon in-medium broadening results in an acceleration of the phi-->K(-)K decay. The increased apparent dilepton branching of the phi mesons, observed recently by the NA50, NA49, and PHENIX Collaborations at RHIC, is interpreted in terms of rescattering of secondary kaons inside the pion matter.
Fratricide of CD8+ cytotoxic T lymphocytes is dependent on cellular activation and perforin‐mediated killing
2004-07-29

Abstract CD8 + CTL mediate the destruction of cells displaying foreign peptides in association with class I MHC molecules. Since CD8 + CTL themselves express class I MHC molecules, a phenomenon known as “fratricide” can be elicited by T cells presenting antigens to other CTL. To gain insight into this mechanism, fratricide was induced in a clone of class I‐restricted CD8 + CTL by incubating the T cells with their agonist ligand, an octamer peptide derived from chicken ovalbumin. Our results indicate that agonist peptide not only stimulates proliferation and cytolysis of CTL but also initiates signaling pathways that are pertinent to T cell activation, including the mobilization of transcription factors. Also consistent with T cell activation, fratricide induced the transcription and translation of the pro‐inflammatory cytokines TNF‐α and IFN‐γ. Finally, the essential role of perforin, as opposed to Fas/FasL, in fratricide was demonstrated by the selective inhibition of cytolysis with an inhibitor of the perforin pathway, the absence of FasL expression on T cells and the presence of lytic granules visible by electron microscopy. Collectively, these findings reveal that fratricide is mediated by T cell activation and perforin‐mediated cytolysis. These results may have implications for the regulation of CD8 + CTL in immune responses.