julilili42/papers huggingface dataset:
Transient Receptor Potential Melastatin 2 Is Required for Lipopolysaccharide-Induced Cytokine Production in Human Monocytes
2010-01-28

Abstract Transient receptor potential melastatin 2 (TRPM2) is a Ca2+-permeable nonselective cation channel that is stimulated by oxidative stress and specifically activated by intracellular ADP-ribose. Because TRPM2 is highly expressed in immunocytes, a role of this channel in inflammation processes has been proposed. The aim of the current study was to determine the function of TRPM2 in LPS-induced cytokine production of human monocytes. Incubation of human primary monocytes with LPS resulted in an upregulation of TRPM2 mRNA, protein, and of ADP-ribose–induced membrane currents. By using short hairpin RNA to downregulate TRPM2 expression in THP-1 monocytes, we demonstrate that TRPM2 is required for the LPS-induced production of IL-6, IL-8, IL-10, and TNF-α. Application of LPS led to a time-dependent increase in intracellular Ca2+ concentrations in THP-1 cells that was clearly reduced by downregulation of TRPM2. Omission of extracellular Ca2+ strongly decreased TNF-α production in TRPM2-expressing cells. Thus, TRPM2-mediated Ca2+ entry is a central mechanism for LPS-induced cytokine production in monocytic cells. The identification of TRPM2 as a major player in this LPS-dependent process makes it a promising tool in modulating monocyte functions.
Effective functional mapping of fMRI data with support‐vector machines
2010-01-28

Abstract There is a growing interest in using support vector machines (SVMs) to classify and analyze fMRI signals, leading to a wide variety of applications ranging from brain state decoding to functional mapping of spatially and temporally distributed brain activations. Studies so far have generated functional maps using the vector of weight values generated by the SVM classification process, or alternatively by mapping the correlation coefficient between the fMRI signal at each voxel and the brain state determined by the SVM. However, these approaches are limited as they do not incorporate both the information involved in the SVM prediction of a brain state, namely, the BOLD activation at voxels and the degree of involvement of different voxels as indicated by their weight values. An important implication of the above point is that two different datasets of BOLD signals, presumably obtained from two different experiments, can potentially produce two identical hyperplanes irrespective of their differences in data distribution. Yet, the two sets of signal inputs could correspond to different functional maps. With this consideration, we propose a new method called Effect Mapping that is generated as a product of the weight vector and a newly computed vector of mutual information between BOLD activations at each voxel and the SVM output. By applying this method on neuroimaging data of overt motor execution in nine healthy volunteers, we demonstrate higher decoding accuracy indicating the greater efficacy of this method. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Mitochondrial haplogroup U is associated with a reduced risk to develop exfoliation glaucoma in the German population
2010-01-28

Abstract Background Various lines of evidence demonstrate the involvement of mitochondrial dysfunction in the pathogenesis of glaucoma. Therefore, mitochondrial DNA is a promising candidate for genetic susceptibility studies on glaucoma. To test the hypothesis that mitochondrial haplogroups influence the risk to develop glaucoma, we genotyped 12 single-nucleotide polymorphisms that define the European mitochondrial DNA haplogroups in healthy controls and two German patient cohorts with either exfoliation glaucoma or the normal tension subgroup of primary open angle glaucoma. Results Mitochondrial haplogroup U was significantly under-represented in patients with exfoliation glaucoma (8.3% compared with 18.9% in controls; p = 0.004). Conclusions People with haplogroup U have a lower risk to develop exfoliation glaucoma. Our results substantiate the suggestion that mitochondrial alterations have an impact on the etiology of glaucoma.
Dark-field scattering microscopy for spectral characterization of polystyrene aggregates
2010-01-28

Light scattering measurements of particle aggregates contain complex information which is difficult to decrypt. Dark-field scattering microscopy in the visible range is used to characterize multi-arranged polystyrene beads. First, measured light scattering spectra of single spheres are compared with the Mie theory. Then, additional spectral measurements of three different sample sets of sphere aggregates are carried out. The aggregates consist of homogeneous spheres and differ in number of spheres, arrangement and contact area. Principal component analysis is used to reduce the number of variables and achieve an accurate classification regarding the aggregate characteristics.
A proinsulin74-90-derived protease-resistant, altered peptide ligand increases TGF-β1 secretion in PBMC from patients with type 1 diabetes mellitus
2010-01-28

Abstract Proinsulin-based protease-resistant altered peptide ligands modulate proinsulin-reactive T cells to secret the anti-inflammatory cytokine TGF-β1. Proinsulin is a major diabetes-associated autoantigen. APL have been shown to manipulate the immune response of T cells. Here, we generated a lysosomal protease-resistant proinsulin74–90-derived APL using a CS-directed amino acid modification approach. These prAPL activated TGF-β1 secretion in proinsulin-reactive T cells from PBMC of patients with T1D. We provide evidence that proinsulin-derived prAPL modulate the cytokine signature of proinsulin-reactive T cells at a micromolar range by increasing anti-inflammatory cytokines, including TGF-β1. Thus, the use of prAPL is a promising tool to mitigate autoaggressive T cells.
The dynamical origin of the multi-planetary system HD 45364
2010-01-29

\\n The recently discovered planetary system HD 45364, which consists of a Jupiter and Saturn-mass planet, is very likely in a 3:2 mean motion resonance. The standard scenario for forming planetary commensurabilities is convergent migration of two planets embedded in a protoplanetary disc. When the planets are initially separated by a period ratio larger than two, convergent migration will most likely lead to a very stable 2:1 resonance. Rapid type III migration of the outer planet crossing the 2:1 resonance is one possible way around this problem. In this paper, we investigate this idea in detail. We present an estimate of the required convergent migration rate and confirm this with N-body and hydrodynamical simulations. If the dynamical history of the planetary system had a phase of rapid inward migration that forms a resonant configuration, we predict that the orbital parameters of the two planets will always be very similar and thus should show evidence of that. We use the orbital parameters from our simulation to calculate a radial velocity curve and compare it to observations. Our model provides a fit that is as good as the previously reported one. The eccentricities of both planets are considerably smaller and the libration pattern is different. Within a few years, it will be possible to observe the planet-planet interaction directly and thus distinguish between these different dynamical states.\\n\\n\\n
Entrapment enhancement of peptide drugs in niosomes
2010-01-29

The objective of this study was to enhance the entrapment of various charged peptide drugs [(bacitracin (BCT), insulin and bovine serum albumin (BSA)] in niosomes by modifying the vesicular charge compositions. Cationic, anionic and neutral niosomes were prepared from sorbitan monostearate (Span 60) or polyoxyethylene sorbitan monostearate (Tween 61), cholesterol (CHL), dimethyldioctadecylammonium bromide (DDAB) and/or dicetyl phosphate (DP) in distilled water, by freeze dried empty liposome (FDEL) method. Morphology and vesicular sizes of the vesicles were investigated by optical microscope, TEM, X-ray diffractometry and dynamic light scattering. The entrapment efficiency of the peptides in niosomes was determined by gel electrophoresis and gel documentation. After reconstitution of the empty niosomal powder in phosphate buffer pH 7.0 containing the peptide drugs, they were oligolamellar membrane structure, with the sizes of 40-60 nm, except the neutral niosomes entrapped with insulin and cationic niosomes entrapped with BSA which showed the sizes of 0.1-1.3 microm and 100-150 nm, respectively. The zeta potential values of neutral, cationic and anionic niosomes entrapped with BSA, insulin and BCT were -22.3 +/- 1.52, -30.7 +/- 2.92 and +22.68+/- 1.31 mV, respectively. The entrapment efficiency of BSA, BCT and insulin in neutral niosomes (Tween 61/CHL at 1 : 1 molar ratio) was 72.94, 69.89 and 10.26%, in cationic niosomes (Tween 61/CHL/DDAB at 1 : 1 : 0.05 molar ratio) was 84.54, 32.85 and 87.15% and in anionic niosomes (Tween 61/CHL/DP at 1 : 1 : 0.05 molar ratio) was 50.13, 90.88 and 44.31%, respectively. The highest entrapment efficiency of BSA, BCT and insulin at 72.94, 90.88 and 87.15 was observed in neutral, anionic and cationic niosomes, respectively. The results from this study has suggested the appropriate niosomal formulation to entrap the peptides with different charges and polarity for pharmaceutical application.
Numerical simulations of highly porous dust aggregates in the low-velocity collision regime
2010-01-29

\\n Context. A highly favoured mechanism of planetesimal formation is collisional growth. Single\\ndust grains hit each other with relative velocities produced by gas flows in the protoplanetary disc. They stick together with \\nvan der Waals forces and form fluffy aggregates up to a centimetre size. The mechanism responsible for any additional growth is \\nunclear since the outcome of aggregate collisions in the relevant velocity and size regime cannot be investigated in the laboratory \\nunder protoplanetary disc conditions. Realistic statistics for dust aggregate collisions beyond decimetre size are required to obtain \\na deeper understanding of planetary growth.\\n Aims. By combining experimental and numerical efforts, we wish to calibrate and validate a computer\\nprogram capable of accurately simulating the macroscopic behaviour of highly porous dust aggregates. After testing its numerical \\nlimitations thoroughly, we check the program especially for a realistic reproduction of the compaction, bouncing, and fragmentation \\nbehaviour. This demonstrates the validity of our code, which will be utilised to simulate dust aggregate collisions and accurately \\ndetermine the fragmentation statistics in future work.\\n Methods. We adopt the smooth particle hydrodynamics (SPH) numerical scheme with extensions to the simulation of solid bodies and a modified \\nversion of the Sirono porosity model. Experimentally measured macroscopic material properties of SiO2 dust are implemented. \\nBy simulating three different setups, we calibrate and test for the compressive strength relation (compaction experiment) and the \\nbulk modulus (bouncing and fragmentation experiments). Data from experiments and simulations will be compared directly.\\n Results. SPH has already proven to be a suitable tool for simulating collisions at rather high velocities. In this work, we demonstrate \\nthat its area of application may be beyond low-velocity experiments and collisions. It can also be used to simulate the behaviour \\nof highly porous objects in this velocity regime to very high accuracy. A correct reproduction of density structures in the \\ncompaction experiment, of the coefficient of restitution in the bouncing experiment, and of the fragment mass distribution in the \\nfragmentation experiment illustrate the validity and consistency of our code\\nfor the simulation of the elastic and plastic properties of the simulated dust aggregates.\\nThe result of this calibration process is an SPH code that can be utilised to investigate the collisional outcome of porous dust \\nin the low-velocity regime.\\n
Effects of spontaneous mutations in PipX functions and regulatory complexes on the cyanobacterium Synechococcus elongatus strain PCC 7942
2010-01-29

In Synechococcus elongatus sp. PCC 7942, PipX forms complexes with P II , a protein found in all three domains of life as an integrator of signals of the nitrogen and carbon balance, and with the cyanobacterial nitrogen regulator NtcA. We recently showed that previous inactivation of pipX facilitates subsequent inactivation of the glnB gene. Here, we show that the three spontaneous pipX point mutations pipX-92delT , pipX160C&gt;T and pipX194T&gt;A, initially found in different glnB strains, are indeed suppressor mutations. When these mutations were reconstructed in the wild-type background, the glnB gene could be efficiently inactivated. Furthermore, the point mutations have different effects on PipX levels, coactivation of NtcA-dependent genes and protein–protein interactions. Further support for an in vivo role of PipX–P II complexes is provided by interaction analysis with the in vivo -generated P II T-loop+7 protein, a P II derivative unable to interact with its regulatory target N -acetyl- l -glutamate kinase, but which retains the ability to bind to PipX. The implications of these results are discussed.
Mechanisms and Kinetics of the Hydrothermal Oxidation of Bulk Titanium Silicon Carbide
2010-01-29

Hydrothermal oxidation of bulk Ti 3 SiC 2 in continuous water flow was studied at 500°–700°C under a hydrostatic pressure of 35 MPa. The oxidation was weak at 500°–600°C and accelerated at 700°C due to the formation of cracks in oxides. The kinetics obeyed a linear time‐law. Due to the high solubility of silica in hydrothermal water, the resulting oxide layers only consisted of titanium oxides and carbon. Besides general oxidation, two special modes are very likely present in current experiments: (1) preferential hydrothermal oxidation of lattice planes perpendicular to the c ‐axis inducing cleavage of grains and (2) uneven hydrothermal oxidation related to the occurrence of TiC and SiC impurity inclusions. Nonetheless the resistance against hydrothermal oxidation is remarkably high up to 700°C.
Nocturnal foraging in a diurnal tropical lizard (Squamata: Gekkonidae: Phelsuma laticauda) on Hawaii
2010-01-29

Animals must eat, necessitating their encounter with food. At least one of the two, predator or prey, must move for the two to meet. Many predators forage for prey by one of two strategies, or foraging modes. They forage either actively, in which case their prey may be mobile or sessile, or passively by waiting in ambush, depending on prey motility. These two foraging modes have been studied extensively in lizards as a model organism (Cooper 1995, Huey &amp; Pianka 1981, Pianka 1966, Pietruzska 1986). Many aspects of a species' biology are correlated with its foraging mode. For example, active foragers employ their chemosensory apparatus for following the prey's trail. Sit-and-wait foragers rely on their eyes to identify approaching prey (Cooper 1995). Other differences are briefly referenced elsewhere (Werner et al . 1997, 2004).
Hamiltonian approach to Yang-Mills theory in Coulomb gauge
2010-01-29

I review results recently obtained within the Hamiltonian approach to Yang-Mills theory in Coulomb gauge.In particular, I will present results for the ghost and gluon propagators and compare these with recent lattice data.Furthermore, I will give an interpretation of the inverse of the ghost form factor as the dielectric function of the Yang-Mills vacuum.Our ansatz for the vacuum wave functional will be checked by means of functional renormalization group flow equations, which are solved for the gluon energy and the ghost form factor. Finally, we calculate the Wilson loop for the vacuum wave functional obtained from the variational approach, using a Dyson equation.
Wnt/β-Catenin Signaling Activates and Determines Hepatic Zonal Expression of Glutathione S-Transferases in Mouse Liver
2010-01-30

Glutathione S-transferases (GSTs) play an essential role in the elimination of xenobiotic-derived electrophilic metabolites and also catalyze certain steps in the conversion of endogenous molecules. Their expression is controlled by different transcription factors, such as the antioxidant-activated Nrf2 or the constitutive androstane receptor. Here, we show that the Wnt/beta-catenin pathway is also involved in the transcriptional regulation of GSTs: GSTm2, GSTm3, and GSTm6 are overexpressed in mouse hepatomas with activating Ctnnb1 (encoding beta-catenin) mutations and in transgenic hepatocytes expressing activated beta-catenin. Inversely, GSTm expression is reduced in mice with hepatocyte-specific knock out of Ctnnb1. Activation of beta-catenin-dependent signaling stimulates GSTm expression in vitro. Activation of beta-catenin in mouse hepatoma cells activates GSTm3 promoter-driven reporter activity, independently of beta-catenin/T-cell factor sites, via a retinoid X receptor-binding site. By contrast, GSTm expression is inhibited upon Ras activation in mouse liver tumors and transgenic hepatocytes. Recent studies by different groups have shown that beta-catenin-dependent signaling is involved in the transcriptional control of "perivenous" expression of various cytochrome P450s in mouse liver, whereas Ras signaling was hypothesized to antagonize the perivenous hepatocyte phenotype. In synopsis with our present results, it now appears that the Wnt/beta-catenin pathway functions as a master regulator of the expression of both phase I and phase II drug-metabolizing enzymes in perivenous hepatocytes from mouse liver.
The large genus limit of the infimum of the Willmore energy
2010-01-31

The Willmore energy of a surface immersed into is the integral of its squared mean curvature. It is known that the infimum of the Willmore energy among all closed oriented surfaces of genus in is attained by a smooth embedded surface, and that for . We show that converges to as goes to infinity.
Variational-splitting time integration of the multi-configuration time-dependent Hartree-Fock equations in electron dynamics
2010-01-31

We discuss the numerical approximation of the solution to the multi-configuration time-dependent Hartree–Fock (MCTDHF) equations in quantum dynamics. The MCTDHF method approximates the high-dimensional wave function of the time-dependent electronic Schrödinger equation by an antisymmetric linear combination of products of functions depending only on three-dimensional spatial coordinates. The equations of motion, obtained via the Dirac–Frenkel time-dependent variational principle, consist of a coupled system of three-dimensional nonlinear partial differential equations and ordinary differential equations. We investigate the convergence properties of a time integrator based on a splitting of the Hamiltonian directly in the variational principle. First-order convergence in the H1-Sobolev and second-order convergence in the L2-norm are established under a solution regularity of H2. As a pre-requisite, we show that the MCTDHF equations have a solution in this Sobolev space if the initial data have such regularity.
Intraoperative electrical stimulation in awake craniotomy: methodological aspects of current practice
2010-02-01

There is increasing evidence that the extent of tumor removal in low-grade glioma surgery is related to patient survival time. Thus, the goal of resecting the largest amount of tumor possible without leading to permanent neurological sequelae is a challenge for the neurosurgeon. Electrical stimulation of the brain to detect cortical and axonal areas involved in motor, language, and cognitive function and located within the tumor or along its boundaries has become an essential tool in combination with awake craniotomy. Based on a literature review, discussions within the European Low-Grade Glioma Group, and illustrative clinical experience, the authors of this paper provide an overview for neurosurgeons, neurophysiologists, linguists, and anesthesiologists as well as those new to the field about the stimulation techniques currently being used for mapping sensorimotor, language, and cognitive function in awake surgery for low-grade glioma. The paper is intended to help the understanding of these techniques and facilitate a comparison of results between users.
Evaluating MT3DMS for Heat Transport Simulation of Closed Geothermal Systems
2010-02-01

Owing to the mathematical similarities between heat and mass transport, the multi‐species transport model MT3DMS should be able to simulate heat transport if the effects of buoyancy and changes in viscosity are small. Although in several studies solute models have been successfully applied to simulate heat transport, these studies failed to provide any rigorous test of this approach. In the current study, we carefully evaluate simulations of a single borehole ground source heat pump (GSHP) system in three scenarios: a pure conduction situation, an intermediate case, and a convection‐dominated case. Two evaluation approaches are employed: first, MT3DMS heat transport results are compared with analytical solutions. Second, simulations by MT3DMS, which is finite difference, are compared with those by the finite element code FEFLOW and the finite difference code SEAWAT. Both FEFLOW and SEAWAT are designed to simulate heat flow. For each comparison, the computed results are examined based on residual errors. MT3DMS and the analytical solutions compare satisfactorily. MT3DMS and SEAWAT results show very good agreement for all cases. MT3DMS and FEFLOW two‐dimensional (2D) and three‐dimensional (3D) results show good to very good agreement, except that in 3D there is somewhat deteriorated agreement close to the heat source where the difference in numerical methods is thought to influence the solution. The results suggest that MT3DMS can be successfully applied to simulate GSHP systems, and likely other systems with similar temperature ranges and gradients in saturated porous media.
Z-suture: a new knotless technique for transscleral suture fixation of intraocular implants
2010-02-01

The presented Z-suture is a simple, rapid and safe knotless technique that facilitates transscleral suture fixation of various intraocular implants in the ciliary sulcus, such as sutured intraocular lenses, artificial iris prostheses and iris diaphragms. As the knotless approach reliably avoids suture erosion, external fixation can be performed without any protecting scleral flaps or lamellar grooves. The needle is simply passed through the sulcus and the emerging polypropylene suture is secured in the sclera using a zigzag-shaped intrascleral suture (Z-suture). Each pass starts directly adjacent to the exiting site. Five passes are sufficient to reliably fix the suture so that it resists even maximum tractive forces. Once this procedure is done, the suture can be cut without any knot. By avoiding suture knots, and hence the need for intrascleral flaps, this knotless approach may help to reduce suture-related complications such as scleral atrophy, suture erosion and infections.