Temperature dependence of circular DNA topological states

Circular double stranded DNA has different topological states which are defined by their linking numbers. Equilibrium distribution of linking numbers can be obtained by closing a linear DNA into a circle by ligase. Using Monte Carlo simulation, we predict the temperature dependence of the linking number distribution of small circular DNAs. Our predictions are based on flexible defect excitations resulted from local melting or unstacking of DNA base pairs. We found that the reduced bending rigidity alone can lead to measurable changes of the variance of linking number distribution of short circular DNAs. If the defect is accompanied by local unwinding, the effect becomes much more prominent. The predictions can be easily investigated in experiments, providing a new method to study the micromechanics of sharply bent DNAs and the thermal stability of specific DNA sequences. Furthermore, the predictions are directly applicable to the studies of binding of DNA distorting proteins that can locally reduce DNA rigidity, form DNA kinks, or introduce local unwinding.Comment: 15 pages in preprint format, 4 figure

N′-[(E)-2-Hydroxy­benzyl­idene]-5-methyl­isoxazole-4-carbohydrazide monohydrate

In the structure of the title compound, C12H11N3O3·H2O, the dihedral angle formed by the benzene and isoxazole rings is 2.03 (8)°. The mol­ecular conformation is stabilized by an intra­molecular O—H⋯N hydrogen bond. In the crystal structure, mol­ecules are linked into a three-dimesional network by inter­molecular N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds, and by π–π stacking inter­actions involving adjacent benzene and isoxazole rings [centroid–centroid separation = 3.663 (2) Å]

Discontinuous Galerkin Immersed Finite Volume Element Method for Anisotropic Flow Models in Porous Medium

By choosing the trial function space to the immersed finite element space and the test function space to be piecewise constant function space, we develop a discontinuous Galerkin immersed finite volume element method to solve numerically a kind of anisotropic diffusion models governed by the elliptic interface problems with discontinuous tensor-conductivity. The existence and uniqueness of the discrete scheme are proved, and an optimal-order energy-norm estimate and L2-norm estimate for the numerical solution are derived

Dopamine D 4 Receptors Modulate GABAergic Signaling in Pyramidal Neurons of Prefrontal Cortex

The D 4 modulation of GABA A receptor currents was blocked by protein kinase A (PKA) activation and occluded by PKA inhibition. Inhibiting the catalytic activity of protein phosphatase 1 (PP1) also eliminated the effect of PD168077 on GABA A currents. Furthermore, disrupting the association of the PKA/PP1 complex with its scaffold protein Yotiao significantly attenuated the D 4 modulation of GABA A currents, suggesting that Yotiao-mediated targeting of PKA/PP1 to the vicinity of GABA A receptors is required for the dopaminergic signaling. Together, our results show that activation of D 4 receptors in PFC pyramidal neurons inhibits GABA A channel functions by regulating the PKA/PP1 signaling complex, which could underlie the D 4 modulation of PFC neuronal activity and the actions of antipsychotic drugs

Rotation and alignment of high-jj orbitals in transfermium nuclei

The structure of nuclei with $Z\sim100$ is investigated systematically by the Cranked Shell Model (CSM) with pairing correlations treated by a Particle-Number Conserving (PNC) method. In the PNC method, the particle number is conserved and the Pauli blocking effects are taken into account exactly. By fitting the experimental single-particle spectra in these nuclei, a new set of Nilsson parameters ($\kappa$ and $\mu$) is proposed. The experimental kinematic moments of inertia and the band-head energies are reproduced quite well by the PNC-CSM calculations. The band crossing, the effects of high-$j$ intruder orbitals and deformation are discussed in detail.Comment: To appear in the Proceedings of the International Nuclear Physics Conference (INPC2013), June 2-7, 2013, Florence, Ital

Probucol alleviates atherosclerosis and improves high density lipoprotein function

<p>Abstract</p> <p>Background</p> <p>Probucol is a unique hypolipidemic agent that decreases high density lipoprotein cholesterol (HDL-C). However, it is not definite that whether probucol hinders the progression of atherosclerosis by improving HDL function.</p> <p>Methods</p> <p>Eighteen New Zealand White rabbits were randomly divided into the control, atherosclerosis and probucol groups. Control group were fed a regular diet; the atherosclerosis group received a high fat diet, and the probucol group received the high fat diet plus probucol. Hepatocytes and peritoneal macrophages were isolated for [³H] labeled cholesterol efflux rates and expression of ABCA1 and SR-B1 at gene and protein levels; venous blood was collected for serum paraoxonase 1, myeloperoxidase activity and lipid analysis. Aorta were prepared for morphologic and immunohistochemical analysis after 12 weeks.</p> <p>Results</p> <p>Compared to the atherosclerosis group, the paraoxonase 1 activity, cholesterol efflux rates, expression of ABCA1 and SR-BI in hepatocytes and peritoneal macrophages, and the level of ABCA1 and SR-BI in aortic lesions were remarkably improved in the probucol group, But the serum HDL cholesterol concentration, myeloperoxidase activity, the IMT and the percentage plaque area of aorta were significantly decreased.</p> <p>Conclusion</p> <p>Probucol alleviated atherosclerosis by improving HDL function. The mechanisms include accelerating the process of reverse cholesterol transport, improving the anti-inflammatory and anti-oxidant functions.</p

1-(4-Methyl­phenyl­diazo­nium­yl)-2-naphtholate

In the title compound, C17H14N2O, the dihedral angle between the benzene ring and naphthalene ring system is 11.0 (3)°. The azo group adopts an anti configuration and an intra­molecular N—H⋯O hydrogen bond exists. Mol­ecules are packed by π–π inter­actions between adjacent mol­ecule (closest approach between centroids of benzene and naphthalene rings of 3.501 Å)

2-(1,3-Dibenzyl­imidazolidin-2-yl­idene)malononitrile

In the title mol­ecule, C20H18N4, the imidazolidine ring makes dihedral angles of 86.74 (2) and 81.18 (3)° with the two phenyl rings. In the absence of classical inter­molecular inter­actions, the crystal packing is stabilized by van der Waals forces