julilili42/papers huggingface dataset:
Assessing Acute Ventricular Volume Changes by Intracardiac Impedance in a Chronic Heart Failure Animal Model
2009-08-19

Background: Implantable device diagnostics may play an essential role in simplifying the care of heart failure patients by providing fundamental insights into their complex clinical patterns. Early recognition of heart failure progression by a continuous hemodynamic monitoring would allow for timely therapeutic interventions to prevent decompensation and hospitalization. In this study, the feasibility of assessing ventricular volume changes by implant‐based measurements of intracardiac impedance was tested in a heart failure animal model. Methods: Heart failure was induced in five minipigs by high‐rate pacing over 3 weeks. During a final open‐chest examination a graded dobutamine stress test was performed. Stroke volume (SV) was measured by an ultrasonic flow probe at the ascending aorta. End diastolic pressure (EDP) and maximum pressure slope (dP/dt max ) were calculated from a left ventricular microtip catheter signal. Impedance was measured by an implanted pacemaker between biventricular leads. Stroke impedance (SZ) was calculated as the difference between end‐systolic and end‐diastolic impedance (EDZ). Results: Administration of dobutamine led to an increase in SV (55 ± 16%), dP/dt max (107 ± 89%), and SZ (56 ± 30%). EDP changed by 37 ± 21% whereas EDZ changed by 7.4 ± 4%. Significant correlations were found between SZ and SV (r = 0.88), and between EDZ and EDP (r =−0.82). Conclusion: The strong correlation with SV allows the application of intracardiac impedance measurements for an implant‐based continuous monitoring of cardiac function. Impedance may also be used for hemodynamic optimization of cardiac resynchronization therapy.
Diagnostic synergy of non-invasive cardiovascular magnetic resonance and invasive endomyocardial biopsy in troponin-positive patients without coronary artery disease
2009-08-20

Cardiovascular magnetic resonance imaging and EMB have good diagnostic performances as single techniques in patients with TnI-positive acute chest pain in the absence of CAD. The combined application of CMR and EMB yields a considerable diagnostic synergy by overcoming some limitations of CMR and EMB as individually applied techniques.
Enlargement of the Common Bile Duct in Patients With Acute Graft-Versus-Host Disease: What Does It Mean?
2009-08-20

Temporary dilatation of the common bile duct seems to be a common finding in gastrointestinal GVHD after hematopoietic stem cell transplantation and correlates with bilirubin concentration. This knowledge of fluctuation in bile duct diameter can help to avoid unnecessary tests to evaluate for pathologic causes of biliary dilatation.
Pathologic Fractures in Patients With Multiple Myeloma Undergoing Bisphosphonate Therapy: Incidence and Correlation With Course of Disease
2009-08-20

Pathologic Fractures in Patients With Multiple Myeloma Undergoing Bisphosphonate Therapy: Incidence and Correlation With Course of DiseaseMonika N. Vogel1, Katja Weisel2, Olga Maksimovic1, Sebastian Peters1, Harald Brodoefel1, Claus D. Claussen1 and Marius S. Horger1Audio Available | Share
Detection of multiple infections by Monocystis strains in a single earthworm host using ribosomal internal transcribed spacer sequence variation
2009-08-20

SUMMARY Monocystis sp. are sporocyst-forming apicomplexan parasites common in seminal vesicles of the earthworm Lumbricus terrestris where they may account for temporary castration. This study describes the internal transcribed spacer (ITS) region of the ribosomal cistron of Monocystis sp. This region, including ITS-1, the 5·8S ribosomal RNA gene, and ITS-2, was PCR amplified, cloned, and sequenced for Monocystis sp. isolated from the seminal vesicles of several wild-caught L. terrestris . Our analysis revealed substantial polymorphisms, also within single host organisms, indicating intra-host diversity of parasites. These genetic markers are the first that allow distinction of Monocystis sp. genotypes, opening new avenues for the study of parasite diversity within and between hosts.
Confocal and near-field spectroscopic investigation of P3HT:PCBM organic blend film upon thermal annealing
2009-08-20

The poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM) organic films are widely employed as electronic donor and acceptor in the field of organic film solar cell because of their high photovoltaic conversion efficiency. A home-built parabolic mirror assisted confocal and apertureless near-field optical microscope was used to investigate the degradation behavior of the film and to distinguish the donor and acceptor domains both topographically and optically. Under ambient condition, the degradation rates are decreased in the sequence of pristine P3HT, blend P3HT:PCBM film and pristine PCBM. N2 protection dramatically slows down the film degradation rate. Using confocal spectroscopic mapping, we are able to distinguish the local distributions of P3HT and PCBM. Micrometer PCBM aggregates were observed due to the thermal annealing process. Our experimental methods show the possibility to investigate morphology and the photochemistry properties of the organic solar cell films with high spatial resolution.
Quantifying Quantitative Literacy: Age Heaping and the History of Human Capital
2009-08-21

Age data frequently display excess frequencies at attractive numbers, such as multiples of five. We use this “age heaping” to measure cognitive ability in quantitative reasoning, or “numeracy.” We construct a database of age heaping estimates with exceptional geographic and temporal coverage, and demonstrate a robust correlation of literacy and numeracy, where both can be observed. Extending the temporal and geographic range of our knowledge of human capital, we show that Western Europe had already diverged from the east and reached high numeracy levels by 1600, long before the rise of mass schooling or the onset of industrialization.
Semileptonic decays of double heavy baryons in a relativistic constituent three-quark model
2009-08-21

We study the semileptonic decays of double heavy baryons using a manifestly Lorentz covariant constituent three-quark model. We present complete results on transition form factors between double-heavy baryons for finite values of the heavy quark/baryon masses and in the heavy quark symmetry limit which is valid at and close to zero recoil. Decay rates are calculated and compared to each other in the full theory, keeping masses finite, and also in the heavy quark limit.
Detection of Discontinuous Patterns in Spontaneous Brain Activity of Neonates and Fetuses
2009-08-21

The discontinuous patterns in neonatal magnetoencephalographic (MEG) data are quantified with a novel Hilbert phase (HP) based approach. The expert neurologists' scores were used as the gold standard. The performance of this approach was analyzed using a receiver operating characteristic (ROC) curve, and it was compared with two other approaches, namely spectral ratio (SR) and discrete wavelet transform (DWT) that have been proposed for the detection of discontinuous patterns in neonatal EEG. The area under the ROC curve (AUC) was used as a performance measure. AUCs obtained for SR, HP, and DWT were 0.87, 0.80, and 0.56, respectively. Although the performance of HP was lower than SR, it carries information about the frequency content of the signal that helps to distinguish brain patterns from artifacts such as cardiac residuals. Based on this property, the HP approach was extended to fetal MEG data. Further, using the frequency property of the HP approach, burst duration and interburst interval were computed for the discontinuous patterns detected and they are in agreement with reported values.
Absence of functional Hfe protects mice from invasive Salmonella enterica Serovar Typhimurium infection via induction of lipocalin-2
2009-08-22

Abstract Mutations of HFE are associated with hereditary hemochromatosis, but their influence on host susceptibility to infection is incompletely understood. We report that mice lacking one or both Hfe alleles are protected from septicemia with Salmonella Typhimurium, displaying prolonged survival and improved control of bacterial replication. This increased resistance is paralleled by an enhanced production of the enterochelin-binding peptide lipocalin-2 (Lcn2), which reduces the availability of iron for Salmonella within Hfe-deficient macrophages. Accordingly, Hfe−/−Lcn2−/− macrophages are unable to efficiently control the infection or to withhold iron from intracellular Salmonella. Correspondingly, the protection conferred by the Hfe defect is abolished in Hfe−/− mice infected with enterochelin-deficient Salmonella as well as in Hfe−/−Lcn2−/− mice infected with wild-type bacteria. Thus, by induction of the iron-capturing peptide Lcn2, absence of functional Hfe confers host resistance to systemic infection with Salmonella, thereby providing an evolutionary advantage which may account for the high prevalence of genetic hemochromatosis.
Manipulation of charged residues within the two‐peptide lantibiotic lacticin 3147
2009-08-23

Summary Lantibiotics are antimicrobial peptides which contain a high percentage of post‐translationally modified residues. While most attention has been paid to the role of these critical structural features, evidence continues to emerge that charged amino acids also play a key role in these peptides. Here 16 ‘charge’ mutants of the two‐peptide lantibiotic lacticin 3147 [composed of Ltnα (2+, 2−) and Ltnβ (2+)] were constructed which, when supplemented with previously generated peptides, results in a total bank of 23 derivatives altered in one or more charged residues. When examined individually, in combination with a wild‐type partner or, in some instances, in combination with one another, these mutants reveal the importance of charge at specific locations within Ltnα and Ltnβ, confirm the critical role of the negatively charged glutamate residue in Ltnα and facilitate an investigation of the contribution of positively charged residues to the cationic Ltnβ. From these investigations it is also apparent that the relative importance of the overall charge of lacticin 3147 varies depending on the target bacteria and is most evident when strains with more negatively charged cell envelopes are targeted. These studies also result in, for the first time, the creation of a derivative of a lacticin 3147 peptide (LtnβR27A) which displays enhanced specific activity.
Characterization of MHC Ligands for Peptide Based Tumor Vaccination
2009-08-23

Short peptides derived from cellular proteins may escape complete destruction during protein catabolism and finally serve as a showcase in the immune system. Exposed at the cell surface to scrutiny by T cells, MHC:peptide complexes mediate a highly specific and immediate information transfer from diseased cells to the cellular immune system. Numerous clinical vaccination trials have been carried out employing MHC-presented peptides for T-cell activation with encouraging results but so far without a final breakthrough. In this review, we briefly highlight the molecular basis of MHC-peptide interactions governed by specificity pockets and anchor residues, as summarized in allele-specific peptide motifs. State-of-the-art technology is comprehensively presented and gives an overview of modern mass spectrometric strategies used for qualitative and quantitative analysis of MHC ligands. We describe the details of the HLA-B*3801 peptide motif by comparing features of natural MHC ligands, resulting in a scoring matrix that enables epitope prediction from any viral or tumor antigen. The pronounced individuality in peptide presentation by MHC molecules, as reflected in the highly specific peptide motifs of different MHC allotypes or the tissue-specific MHC ligandomes, represents a current area of interest within this field. Finally, the identification of post-translational modifications--most important phosphorylations--and the promises this holds will be discussed in this chapter.
ATP13A2 variants in early‐onset Parkinson's disease patients and controls
2009-08-24

Abstract Four genes responsible for recessively inherited forms of Parkinson's disease (PD) have been identified, including the recently discovered ATP13A2 ( PARK9 ) gene. Our objective was to investigate the role of this gene in a large cohort of PD patients and controls. We extensively screened all 29 exons of the ATP13A2 coding region in 112 patients with early‐onset PD (EOPD; &lt;40 years) of mostly European ethnic origin and of 55 controls. We identified four carriers (3.6%) of novel single heterozygous ATP13A2 missense changes that were absent in controls. Interestingly, the carrier of one of these variants also harbored two mutations in the Parkin gene. None of the carriers had atypical features previously described in patients with two mutated ATP13A2 alleles (Kufor–Rakeb syndrome). Our data suggest that two mutated ATP13A2 alleles are not a common cause of PD. Although heterozygous variants are present in a considerable number of patients, they are—based on this relatively small sample—not significantly more frequent in patients compared to controls. © 2009 Movement Disorder Society
The outer membrane of a heterocyst‐forming cyanobacterium is a permeability barrier for uptake of metabolites that are exchanged between cells
2009-08-24

Summary The multicellular Anabaena sp. strain PCC 7120 is a filamentous cyanobacterium that can fix N 2 in differentiated cells called heterocysts, which exchange nutritional and regulatory compounds with the neighbour photosynthetic vegetative cells. The outer membrane of this bacterium is continuous along the filament defining a continuous periplasmic space. The Anabaena alr0075 , alr2269 and alr4893 gene products were characterized as Omp85‐like proteins, which are generally involved in outer membrane protein biogenesis. Open reading frame alr2269 is the first gene of an operon that also carries genes for lipopolysaccharide lipid A biosynthesis including alr2270 (an lpxC homologue). Strains carrying inactivating alr2269 or alr2270 constructs showed enhanced sensitivity to erythromycin, SDS, lysozyme and proteinase K suggesting that they produce an outer membrane with increased permeability. These strains further exhibited increased uptake of sucrose, glutamate and, to a lesser extent, a few other amino acids. Increased uptake of the same metabolites was obtained by mechanical fragmentation of wild‐type Anabaena filaments. These results document that the outer membrane is a permeability barrier for metabolites such as sucrose and glutamate, which are subjected to intercellular exchange in the diazotrophic filament of heterocyst‐forming cyanobacteria.
Thermally Induced Radical Hydrosilylation for Synthesis of C18 HPLC phases from Highly Condensed SiH Terminated Silica Surfaces
2009-08-24

Silicon hydride terminated silica surfaces were prepared at high temperatures by a chlorination-reduction sequence. SiH groups are desired for further surface modification as an alternative to the native silanol groups which are unfavorable for RPLC applications. Only few silanol groups remain in these materials and mostly SiH moieties with the highest degree of cross-linking are obtained. The retention properties of basic analytes on the SiH terminated material confirm that the surfaces is mostly free of silanols and that therefore the remaining SiOH groups are bulk species. A reagentless, radical initiated hydrosilylation reaction is introduced for the functionalization of the hydride terminated surface with 1-octadecene. (13)C CP/MAS NMR and DRIFT spectroscopy demonstrate the reaction of the carbon-carbon double bond and the SiH group as well as the linkage of C18 groups to the silica surface. These novel C18 materials show promising performance in RPLC separation, especially for the separation of organic bases.
Severe muscular fasciculations as an uncommon side‐effect due to microdefect of an extension wire in deep brain stimulation
2009-08-24

Additional Supporting Information may be found in the online version of this article. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Background from radioactivity in dark matter detectors
2009-08-24

New generation dark matter experiments aim at exploring the 10 -9 -10 -10 pb cross-section region for the WIMP-nucleon scalar interactions.Neutrons and gamma-rays produced in detector components are the main factors that can limit detector sensitivity.Radioactive background event rates from some detector components (such as copper and stainless steel), as well as from rock and concrete (lab walls), were estimated in this work for a hypothetical dark matter detector based on Ge crystals (for instance EURECA).Different shielding configurations (water, lead, polyethylene) were considered.Neutrons and photons were propagated to the detector using GEANT4.Some requirements for the radiopurity of the materials were deduced from the results of these simulations.Thickness of shielding in different configurations and required gamma discrimination factor were investigated.
Glial Cell-Line Derived Neurotrophic Factor (GDNF) Concentrations in Cerebrospinal Fluid and Serum of Patients with Early Alzheimer's Disease and Normal Controls
2009-08-26

As neurotrophic factors play an important role in development and maintenance of global central nervous system (CNS) function, we supposed that glial cell-line derived neurotrophic factor (GDNF), which has been extensively studied for its survival promoting effects especially concerning catecholaminergic neurons, also plays a significant role in neurodegenerative disease characterized mainly by damage of cholinergic CNS neurons like AD. Here we compared GDNF concentrations in serum and cerebrospinal fluid (CSF) of patients with probable Alzheimer's disease (AD) and normal controls (NC). While GDNF concentrations in CSF were significantly increased in patients with AD (291.7 +/- 85.8 pg/ml) compared with NC subjects (218.7 +/- 93.3 pg/ml, p = 0.012), GDNF concentration of AD patients (486.5 +/- 72.3 pg/ml) in serum were significantly decreased compared with the NC group (711.5 +/- 186.5 pg/ml, p < 0.001). Increased GDNF in CSF of AD might be due to an upregulated expression in CNS as an adaptive process of the impaired brain to enhance neurotrophic support at least in early stages of disease and/or impairment of CSF turnover. Decreased serum concentration of GDNF might be related to altered function of the blood brain barrier thus disturbing clearance or facilitating passover of potentially harmful metabolites.
Test of statistical means for the extrapolation of soil depth point information using overlays of spatial environmental data and bootstrapping techniques
2009-08-26

Abstract Hydrological modelling depends highly on the accuracy and uncertainty of model input parameters such as soil properties. Since most of these data are field surveyed, geostatistical techniques such as kriging, classification and regression trees or more sophisticated soil‐landscape models need to be applied to interpolate point information to the area. Most of the existing interpolation techniques require a random or regular distribution of points within the study area but are not adequate to satisfactorily interpolate soil catena or transect data. The soil landscape model presented in this study is predicting soil information from transect or catena point data using a statistical mean (arithmetic, geometric and harmonic mean) to calculate the soil information based on class means of merged spatial explanatory variables. A data set of 226 soil depth measurements covering a range of 0–6·5 m was used to test the model. The point data were sampled along four transects in the Stubbetorp catchment, SE‐Sweden. We overlaid a geomorphology map (8 classes) with digital elevation model‐derived topographic index maps (2–9 classes) to estimate the range of error the model produces with changing sample size and input maps. The accuracy of the soil depth predictions was estimated with the root mean square error (RMSE) based on a testing and training data set. RMSE ranged generally between 0·73 and 0·83 m ± 0·013 m depending on the amount of classes the merged layers had, but were smallest for a map combination with a low number of classes predicted with the harmonic mean (RMSE = 0·46 m). The results show that the prediction accuracy of this method depends on the number of point values in the sample, the value range of the measured attribute and the initial correlations between point values and explanatory variables, but suggests that the model approach is in general scale invariant. Copyright © 2009 John Wiley &amp; Sons, Ltd.
Macular pigment and fixation after macular translocation surgery
2009-08-26

The combination of MP distribution and fixation analysis allows fixation behaviour to be quantified, even if the fovea morphologically cannot be localised. Our results suggest that the scotoma caused by spreading chorioretinal atrophy is the main cause for reduced visual acuity after MT, and so the MT rotation angle is crucially important.
Planet migration in three-dimensional radiative discs
2009-08-27

The migration of growing protoplanets depends on the thermodynamics of the\\nambient disc. Standard modelling, using locally isothermal discs, indicate in\\nthe low planet mass regime an inward (type-I) migration. Taking into account\\nnon-isothermal effects, recent studies have shown that the direction of the\\ntype-I migration can change from inward to outward. In this paper we extend\\nprevious two-dimensional studies, and investigate the planet-disc interaction\\nin viscous, radiative discs using fully three-dimensional radiation\\nhydrodynamical simulations of protoplanetary accretion discs with embedded\\nplanets, for a range of planetary masses.\\n We use an explicit three-dimensional (3D) hydrodynamical code NIRVANA that\\nincludes full tensor viscosity. We have added implicit radiation transport in\\nthe flux-limited diffusion approximation, and to speed up the simulations\\nsignificantly we have newly adapted and implemented the FARGO-algorithm in a 3D\\ncontext.\\n First, we present results of test simulations that demonstrate the accuracy\\nof the newly implemented FARGO-method in 3D. For a planet mass of 20 M_earth we\\nthen show that the inclusion of radiative effects yields a torque reversal also\\nin full 3D. For the same opacity law used the effect is even stronger in 3D\\nthan in the corresponding 2D simulations, due to a slightly thinner disc.\\nFinally, we demonstrate the extent of the torque reversal by calculating a\\nsequence of planet masses. Through full 3D simulations of embedded planets in\\nviscous, radiative discs we confirm that the migration can be directed outwards\\nup to planet masses of about 33 M_earth. Hence, the effect may help to resolve\\nthe problem of too rapid inward migration of planets during their type-I phase.\\n