julilili42/papers huggingface dataset:
Perception and Understanding of Others' Actions and Brain Connectivity
2008-02-05

Perception and understanding of dispositions and intentions of others through their actions are of immense importance for adaptive daily-life behavior and social communication. Here we ask whether, and, if so, how this ability is impaired in adolescents who were born premature and suffer early periventricular damage, periventricular leukomalacia (PVL) that affects brain connectivity. The visual event arrangement (EA) task was administered to PVL patients and two control groups, premature-born and term-born adolescents without brain abnormalities on a magnetic resonance imaging scan. Performance on the EA task was significantly lower in PVL patients as compared with controls. No difference was found between premature-born participants without lesions and term-born controls. Performance on the EA task was inversely related to the volumetric extent of lesions in the parieto-occipital regions of both hemispheres and, in particular, to the right temporal periventricular lesions. Whereas our earlier work reveals that compromised visual processing of biological motion, impairments in visual navigation, and other visual-perceptual disabilities in PVL patients are associated with parieto-occipital lesions, difficulties in the visual EA task solely are specifically linked to the right temporal periventricular lesions. For the first time, we show that the severity of the right temporal PVL can serve as a predictor of the ability for perception and understanding of others' actions. We assume that impairments in this ability in PVL patients are caused by disrupted brain connectivity to the right temporal cortex, a key node of the social brain.
Efficacy of Ketamine in Anesthetic Dosage for the Treatment of Refractory Complex Regional Pain Syndrome: An Open-Label Phase II Study
2008-02-06

This open-label trial suggests benefit in pain reduction, associated CRPS symptoms, improved quality of life and ability to work following anesthetic ketamine in previously refractory CRPS patients. However, a randomized controlled trial will be necessary to prove its efficacy.
Crustal oscillations of slowly rotating relativistic stars
2008-02-06

We study low-amplitude crustal oscillations of slowly rotating relativistic stars consisting of a central fluid core and an outer thin solid crust. We estimate the effect of rotation on the torsional toroidal modes and on the interfacial and shear spheroidal modes. The results compared against the Newtonian ones for wide range of neutron star models and equations of state.
Modulation of murine embryonic stem cell–derived CD41+c-kit+ hematopoietic progenitors by ectopic expression of Cdx genes
2008-02-06

Abstract Cdx1, Cdx2, and Cdx4 comprise the caudal-like Cdx gene family in mammals, whose homologues regulate hematopoietic development in zebrafish. Previously, we reported that overexpression of Cdx4 enhances hematopoietic potential from murine embryonic stem cells (ESCs). Here we compare the effect of ectopic Cdx1, Cdx2, and Cdx4 on the differentiation of murine ESC-derived hematopoietic progenitors. The 3 Cdx genes differentially influence the formation and differentiation of hematopoietic progenitors within a CD41+c-kit+ population of embryoid body (EB)–derived cells. Cdx1 and Cdx4 enhance, whereas Cdx2 strongly inhibits, the hematopoietic potential of CD41+ckit+ EB-derived cells, changes that are reflected by effects on hematopoietic lineage-specific and Hox gene expression. When we subject stromal cell and colony assay cultures of EB-derived hematopoietic progenitors to ectopic expression of Cdx genes, Cdx4 dramatically enhances, whereas Cdx1 and Cdx2 both inhibit hematopoietic activity, probably by blocking progenitor differentiation. These data demonstrate distinct effects of Cdx genes on hematopoietic progenitor formation and differentiation, insights that we are using to facilitate efforts at in vitro culture of hematopoietic progenitors from ESC. The behavior of Cdx genes in vitro suggests how derangement of these developmental regulators might contribute to leukemogenesis.
Think to Move: a Neuromagnetic Brain-Computer Interface (BCI) System for Chronic Stroke
2008-02-08

Background and Purpose— Stroke is a leading cause of long-term motor disability among adults. Present rehabilitative interventions are largely unsuccessful in improving the most severe cases of motor impairment, particularly in relation to hand function. Here we tested the hypothesis that patients experiencing hand plegia as a result of a single, unilateral subcortical, cortical or mixed stroke occurring at least 1 year previously, could be trained to operate a mechanical hand orthosis through a brain-computer interface (BCI). Methods— Eight patients with chronic hand plegia resulting from stroke (residual finger extension function rated on the Medical Research Council scale=0/5) were recruited from the Stroke Neurorehabilitation Clinic, Human Cortical Physiology Section of the National Institute for Neurological Disorders and Stroke (NINDS) (n=5) and the Clinic of Neurology of the University of Tübingen (n=3). Diagnostic MRIs revealed single, unilateral subcortical, cortical or mixed lesions in all patients. A magnetoencephalography-based BCI system was used for this study. Patients participated in between 13 to 22 training sessions geared to volitionally modulate μ rhythm amplitude originating in sensorimotor areas of the cortex, which in turn raised or lowered a screen cursor in the direction of a target displayed on the screen through the BCI interface. Performance feedback was provided visually in real-time. Successful trials (in which the cursor made contact with the target) resulted in opening/closing of an orthosis attached to the paralyzed hand. Results— Training resulted in successful BCI control in 6 of 8 patients. This control was associated with increased range and specificity of μ rhythm modulation as recorded from sensors overlying central ipsilesional (4 patients) or contralesional (2 patients) regions of the array. Clinical scales used to rate hand function showed no significant improvement after training. Conclusions— These results suggest that volitional control of neuromagnetic activity features recorded over central scalp regions can be achieved with BCI training after stroke, and used to control grasping actions through a mechanical hand orthosis.
Multiplexed Cell Signaling Analysis of Human Breast Cancer Applications for Personalized Therapy
2008-02-08

Phosphoprotein driven cellular signaling events represent most of the new molecular targets for cancer treatment. Application of reverse-phase protein microarray technology for the study of ongoing signaling activity within breast tumor specimens holds great potential for elucidating and profiling signaling activity in real-time for patient-tailored therapy. Analysis of laser capture microdissection primary human breast tumors and metastatic lesions reveals pathway specific profiles and a new way to classify cancer based on functional signaling portraits. Moreover, the data demonstrate the requirement of laser capture microdissection for analysis and reveal the metastasis-specific changes that occur within a new microenvironment. Analysis of biopsy material from clinical trials for targeted therapeutics demonstrates the feasibility and utility of comprehensive signal pathway activation profiling for molecular analysis.
Array-Based Resequencing Assay for Mutations Causing Hypertrophic Cardiomyopathy
2008-02-08

Abstract Background: Dissecting the complex genetic basis of hypertrophic cardiomyopathy (HCM) may be key to both better understanding and optimally managing this most prevalent genetic cardiovascular disease. An array-based resequencing (ABR) assay was developed to facilitate genetic testing in HCM. Methods: An Affymetrix resequencing array and a single long-range PCR protocol were developed to cover the 3 most commonly affected genes in HCM, MYH7 (myosin, heavy chain 7, cardiac muscle, beta), MYBPC3 (myosin binding protein C, cardiac), and TNNT2 [troponin T type 2 (cardiac)]. Results: The assay detected the underlying point mutation in 23 of 24 reference samples and provided pointers toward identifying a G insertion and a 3-bp deletion. The comparability of array-based assay results to conventional capillary sequencing was ≥99.9%. Both techniques detected 1 heterozygous variant that was missed by the other method. Conclusions: The data provide evidence that ABR can substantially reduce the high workload previously associated with a genetic test for HCM. Therefore, the HCM array could facilitate large-scale studies aimed at broadening the understanding of the genetic and phenotypic diversity of HCM and related cardiomyopathies.
Antibody and cytokine responses in Dracunculus medinensis patients at distinct states of infection
2008-02-08

Dracunculiasis is a promising candidate for eradication, but transmission of Dracunculus medinensis and recrudescence of the disease have been observed repeatedly. In the present investigation, the D. medinensis-specific cellular cytokine response profiles and the parasite-specific antibody subclass reactivity were evaluated in dracunculiasis patients at distinct states of infection. Analysis of the cellular cytokine response in dracunculiasis patients disclosed a D. medinensis antigen-specific depression of IFN-gamma production with patent D. medinensis infection, while the T helper type 2 cytokine IL-10 was similar in patent, post-patent and control individuals, and IL-5 production was always the highest in controls. In parallel, diminished IFN-gamma and IL-12 responses to antigens from Ascaris lumbricoides, Entamoeba histolytica and mycobacteria were observed in patent and post-patent dracunculiasis cases. The parasite-specific IgG(1) and IgG(4) subclass reactivity profiles corresponded with the D. medinensis infection state, and a clear distinction between patent and post-patent patients and controls was found. Overall a depressed cytokine release was observed with patent D. medinensis, which extended beyond the parasite-specific immune responsiveness. The detection of D. medinensis-specific IgG(1) and IgG(4) isotypes may help to distinguish newly exposed, patent and post-patent D. medinensis infections.
The dihydropyridine isradipine inhibits the murine but not the bovine a‐wave response of the electroretinogram
2008-02-08

Abstract. Purpose: In order to record light‐evoked responses from photoreceptor cells and the higher neuronal retinal network, the isolated vertebrate retina represents a sensitive tool for basic research of retinal function and for testing the toxicity of ocular therapeutics. In the past, this in vitro technique was optimized for frog and bovine retina; it should be transferred now to the isolated murine retina because the model could allow for functional testing of genes involved in retinal signalling using wild‐type and gene‐inactivated mice. Thus, alterations in the electroretinogram (ERG) may reveal differences in retinal information processing because of the inactivation of a specific gene. Methods: We used a superfused vertebrate retina assay to test bovine and murine retina. Results: In order to evaluate the sensitivity of the ERG recording technique from the isolated murine retina, we first determined the light intensity response and the stability of the a‐wave amplitude during ERG recording, which did not differ between the species. However, testing the dihydropyridine sensitivity of the a‐wave, we found that the murine a‐wave was highly sensitive towards racemic isradipine (8–25 n M ) but the bovine retina a‐wave was not. A similar species‐dependent difference was observed for mibefradil (10 μ M ). Conclusion: Murine and bovine retina differ with respect to transretinal signalling. At the level of photoreceptor cells, the ERG/a‐wave is modulated by isradipine‐sensitive voltage‐gated Ca 2+ channels, which trigger feedback signalling to photoreceptors.
Scavenger receptors: targets for antiplatelet therapies?
2008-02-08

Scavenger receptors are increasingly recognized as playing a critical role in atherothrombosis.1 A new study presented by Valiyaveettil and colleagues in this issue of Blood demonstrates that oxidatively modified high-density lipoprotein (OxHDL) exhibits potent antiplatelet activity via the platelet scavenger receptor B type I (SR-BI).
Detection of Anaerobic Bacteria in High Numbers in Sputum from Patients with Cystic Fibrosis
2008-02-09

A range of anaerobic species are present in large numbers in the lungs of patients with CF. If these anaerobic bacteria are contributing significantly to infection and inflammation in the CF lung, informed alterations to antibiotic treatment to target anaerobes, in addition to the primary infecting pathogens, may improve management.
When Traditions Change and Virtues Become Obstacles: Skill Formation in Britain and Germany
2008-02-11

In recent years, there has been an increasing interest in cross-national comparisons of education and training systems. But how similar or different are national skill systems? To what extent, how, and why do they change? The public and scientific discourse about the modern “knowledge society” seems to imply that they will follow uniform trends rather than take specific pathways. Still, the attractiveness of particular national “models” may change over time, with varying success and different demands put on them. This leads to the following general questions:
Expression of 3‐hydroxyisobutyrate dehydrogenase in cultured neural cells
2008-02-12

Abstract The branched‐chain amino acids (BCAAs) – isoleucine, leucine, and valine – belong to the limited group of substances transported through the blood–brain barrier. One of the functions they are thought to have in brain is to serve as substrates for meeting parenchymal energy demands. Previous studies have shown the ubiquitous expression of a branched‐chain alpha‐keto acid dehydrogenase among neural cells. This enzyme catalyzes the initial and rate‐limiting step in the irreversible degradative pathway for the carbon skeleton of valine and the other two branched‐chain amino acids. Unlike the acyl‐CoA derivates in the irreversible part of valine catabolism, 3‐hydroxyisobutyrate could be expected to be released from cells by transport across the mitochondrial and plasma membranes. This could indeed be demonstrated for cultured astroglial cells. Therefore, to assess the ability of neural cells to make use of this valine‐derived carbon skeleton as a metabolic substrate for the generation of energy, we investigated the expression in cultured neural cells of the enzyme processing this hydroxy acid, 3‐hydroxyisobutyrate dehydrogenase (HIBDH). To achieve this, HIBDH was purified from bovine liver to serve as antigen for the production of an antiserum. Affinity‐purified antibodies against HIBDH specifically recognized the enzyme in liver and brain homogenates. Immunocytochemistry demonstrated the ubiquitous expression of HIBDH among cultured glial (astroglial, oligodendroglial, microglial, and ependymal cells) and neuronal cells. Using an RT‐PCR technique, these findings were corroborated by the detection of HIBDH mRNA in these cells. Furthermore, immunofluorescence double‐labeling of astroglial cells with antisera against HIBDH and the mitochondrial marker pyruvate dehydrogenase localized HIBDH to mitochondria. The expression of HIBDH in neural cells demonstrates their potential to utilize valine imported into the brain for the generation of energy.
Erratum: Improved Landau gauge fixing and the suppression of finite-volume effects of the lattice gluon propagator [Phys. Rev. D77, 014504 (2008)]
2008-02-12

For the gluon propagator of pure SU(2) lattice gauge theory in the Landau\\ngauge we investigate the effect of Gribov copies and finite-volume effects.\\nConcerning gauge fixing, we enlarge the accessible gauge orbits by adding\\nnon-periodic Z(2) gauge transformations and systematically employ the simulated\\nannealing algorithm. Strategies to keep all Z(2) sectors under control within\\nreasonable CPU time are discussed. We demonstrate that the finite-volume\\neffects in the infrared regime become ameliorated. Reaching a physical volume\\nof about (6.5 fm)^4, we find that the propagator, calculated with the indicated\\nimprovements, becomes flat in the region of smallest momenta. First signs in 4d\\nof a final decrease towards vanishing momentum are discussed.\\n
Local Delivery of Paclitaxel to Inhibit Restenosis during Angioplasty of the Leg
2008-02-13

Use of paclitaxel-coated angioplasty balloons during percutaneous treatment of femoropopliteal disease is associated with significant reductions in late lumen loss and target-lesion revascularization. No significant benefit is seen with the use of a paclitaxel-containing contrast medium. (ClinicalTrials.gov number, NCT00156624 [ClinicalTrials.gov].).
Silica on Silicon Carbide
2008-02-13

Abstract Silicon carbide (SiC) as both the most important non-oxide ceramic and promising semiconductor material grows stoichiometric SiO 2 as its native oxide. During passive oxidation, a surface transformation of SiC into silica takes place causing bulk volume and bulk mass increase. This review summarizes state-of-the-art information about the structural aspects of silicon carbide, silica, and SiC–SiO 2 interfaces and discusses physicochemical properties and kinetics of the processes involved. A special section describes the electronic properties of carbide–oxide interfaces, which are inferior compared to Si–SiO 2 interfaces, limiting the use of SiC-based electronics. In the oxidation of SiC there is a variety of parameters (e.g., porosity, presence of sintering aids, impurities, crystallographic orientation, surface treatment, and atmospheric composition) influencing the process. Therefore, the kinetics can be complex and will be discussed in detail. Nonetheless, a general linear-parabolic time-law can be found for most SiC materials for passive oxidation, thus indicating a mainly diffusion-controlled mechanism. The pronounced anisotropy of SiC expresses itself by quite different oxidation rates for the various crystallographic faces. Manifold impact factors are reflected by oxidation rate-constants for silicon carbide that vary over orders of magnitude. The understanding of SiC oxidation and silica formation is still limited; therefore, different oxidation models are presented and evaluated in the light of current knowledge. Keywords: silicasilicon carbidegrowth kineticsoxidationinterface ACKNOWLEDGMENTS This work was partially supported by the Deutsche Forschungsgemeinschaft (DFG) through Ni299/12-1. The authors thank (in alphabetical order): Valerie Afanas'ev (University of Leuven), Matthias Bickermann (University of Erlangen-Nürnberg), Kai-Chieh Chang (Seagate Technology, Pittsburgh), Fabien Devynck (Ecole Polytechnique Fédérale de Lausanne), Andrei Maltsev (Caracal Inc., Ford City), and Thomas Wagner (University of Tübingen) for much appreciated and most valuable discussion.
The outer membrane form of the mitochondrial protein Mcr1 follows a TOM‐independent membrane insertion pathway
2008-02-13

The yeast gene MCR1 encodes two isoforms of the mitochondrial NADH‐cytochrome b 5 reductase. One form is embedded in the outer membrane whereas the other is located in the intermembrane space (IMS). In the present work we investigated the biogenesis of the outer membrane form. We demonstrate that while the IMS form crosses the outer membrane via the translocase of the outer mitochondrial membrane (TOM) complex, the other form is integrated into the outer membrane by a process that does not require any of the known import components at the outer membrane. Thus, the import pathways of the two forms diverge in a stage before the encounter with the TOM complex and their mechanism of biogenesis represents a unique example how to achieve dual localization within one organelle.
Mastering ectomycorrhizal symbiosis: the impact of carbohydrates
2008-02-14

Mycorrhiza formation is the consequence of a mutualistic interaction between certain soil fungi and plant roots that helps to overcome nutritional limitations faced by the respective partners. In symbiosis, fungi contribute to tree nutrition by means of mineral weathering and mobilization of nutrients from organic matter, and obtain plant-derived carbohydrates as a response. Support with easily degradable carbohydrates seems to be the driving force for fungi to undergo this type of interaction. As a consequence, the fungal hexose uptake capacity is strongly increased in Hartig net hyphae of the model fungi Amanita muscaria and Laccaria bicolor. Next to fast carbohydrate uptake and metabolism, storage carbohydrates are of special interest. In functional A. muscaria ectomycorrhizas, expression and activity of proteins involved in trehalose biosynthesis is mainly localized in hyphae of the Hartig net, indicating an important function of trehalose in generation of a strong carbon sink by fungal hyphae. In symbiosis, fungal partners receive up to approximately 19 times more carbohydrates from their hosts than normal leakage of the root system would cause, resulting in a strong carbohydrate demand of infected roots and, as a consequence, a more efficient plant photosynthesis. To avoid fungal parasitism, the plant seems to have developed mechanisms to control carbohydrate drain towards the fungal partner and link it to the fungus-derived mineral nutrition. In this contribution, current knowledge on fungal strategies to obtain carbohydrates from its host and plant strategies to enable, but also to control and restrict (under certain conditions), carbon transfer are summarized.
Two-photon decay width of the sigma meson
2008-02-14

We shortly report on the two-photon decay width of the light -meson interpreted as a quarkonium state. Results are given in dependence on the -mass and the constituent mass of the light quark. The triangle quark-loop diagram, responsible for the two-photon transition, is carefully evaluated: a term in the transition amplitude, often omitted in literature, results in destructive interference with the leading term. As a result we show that the two-photon decay width of the in the quarkonium picture is less than 1 keV for the physical range of parameters.
Genotypic variation and structure in Australian populations of the aphid Schoutedenia lutea
2008-02-14

The genotypic variation and genetic structure of populations of the aphid Schoutedenia lutea were investigated in the Sydney area of Australia. The typical growth curve of an aphid population was observed: exponential increase in spring (September-October), highest density in the summer (early January), and a collapse by autumn (early March). During the growth period, the frequency of alatae decreases, but the frequency of sexual morphs (oviparae, males) is fairly constant. Three enzyme markers were used to study genotypic variation. Only 11 out of 27 possible genotypes were found, There was no change in genotype frequencies throughout the growth period. To investigate the genetic population structure, aphids were sampled from twigs within and among bushes of Breynia oblongifolia from two ecologically different areas (Cumberland State Forest, Pearl Beach). Analysis of heterogeneity revealed that genetic variation on the host plants of aphids contributes as much as 61 % to the total heterogeneity, whereas the effect of areas was 23 %. The results are discussed with respect to life cycle components and migration of the aphid, and are compared with results from Macrosiphum rosae in Europe.