Diaqua­bis{[1-hydr­oxy-2-(1H-imidazol-3-ium-1-yl)ethane-1,1-di­yl]bis­(hydrogen phospho­nato)}manganese(II)

In the title compound, [Mn(C5H9N2O7P2)2(H2O)2], the MnII atom (site symmetry ) is coordinated by four phos­pho­n­ate O atoms from a pair of partially deprotonated 1-hydr­oxy-2-(imidazol-3-yl)ethane-1,1-bis­phophonic acid ligands (imhedpH3 −) and two water mol­ecules, resulting in a slightly distorted trans-MnO6 octa­hedral geometry for the metal ion. In the ligands, the imidazole units are protonated and two of the hydr­oxy O atoms of the phospho­nate groups are deprotonated and chelate the MnII, thus forming the neutral mol­ecule of the title compound. The two protonated O atoms within the phospho­nate groups of one imhedpH3 − ligand act as hydrogen-bond acceptors for a bifurcated hydrogen bond originating from the coordinated water mol­ecule. The phospho­nate units of neigboring mol­ecules are connected with their equivalents in neighboring mol­ecules via two types of inversion-symmetric hydrogen-bonding arrangements with four and two strong O—H⋯O hydrogen bonds, respectively. The two inter­actions connect mol­ecules into infinite chains along [111] and [110], in combination forming a tightly hydrogen-bonded three-dimensional supra­molecular network. This network is further stabilized by additional hydrogen bonds between the protonated imidazole units and one of the coordinated P—O O atoms and by additional O—H⋯O hydrogen bonds between the water mol­ecules and the P=O O atoms of neigboring mol­ecules

2-(4-Chloro­phen­yl)-3-p-tolyl-1,3-thia­zolidin-4-one

The title compound, C16H14ClNOS, a potent anti­bacterial chemical, features a dihedral angle of 49.4 (1)° between the 4-tolyl and thia­zolidinone rings, and a dihedral angle of 87.2 (5)° between the thia­zolidinone and 4-chloro­phenyl rings

Poly[penta-μ-aqua-μ6-methyl­ene­disulfonato-μ5-methyl­enedisulfonato-tetra­sodium(I)]

The title compound, [Na4(CH2O6S2)2(H2O)5]n, was crystallized from an aqueous solution. The sodium ions are surrounded and bridged by O atoms from coordinated water mol­ecules and sulfonate ions in a three-dimensional neutral network. The crystal structure is also stabilized by an intricate system of hydrogen bonds

Detecting CD20-Rituximab interaction forces using AFM single-molecule force spectroscopy

The invention of atomic force microscopy (AFM) has provided new technology for measuring specific molecular interaction forces. Using AFM single-molecule force spectroscopy (SMFS) techniques, CD20-Rituximab rupture forces were measured on purified CD20 proteins, Raji cells, and lymphoma patient B cells. Rituximab molecules were linked onto AFM tips using AFM probe functionalization technology, and purified CD20 proteins were attached to mica using substrate functionalization technology. Raji cells (a lymphoma cell line) or lymphoma patient cells were immobilized on a glass substrate via electrostatic adsorption and chemical fixation. The topography of the purified CD20 proteins, Raji cells, and patient lymphoma cells was visualized using AFM imaging and the differences in the rupture forces were analyzed and measured. The results showed that the rupture forces between the CD20 proteins on Raji cells and Rituximab were markedly smaller than those for purified CD20 proteins and CD20 proteins on lymphoma patient B cells. These findings provide an effective experimental method for investigating the mechanisms underlying the variable efficacy of Rituximab. © 2011 Science China Press and Springer-Verlag Berlin Heidelberg.Link_to_subscribed_fulltex

Abnormalities of White Matter Microstructure in Unmedicated Obsessive-Compulsive Disorder and Changes after Medication

BACKGROUND: Abnormalities of myelin integrity have been reported in obsessive-compulsive disorder (OCD) using multi-parameter maps of diffusion tensor imaging (DTI). However, it was still unknown to what degree these abnormalities might be affected by pharmacological treatment. OBJECTIVE: To investigate whether the abnormalities of white matter microstructure including myelin integrity exist in OCD and whether they are affected by medication. METHODOLOGY AND PRINCIPAL FINDINGS: Parameter maps of DTI, including fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD), were acquired from 27 unmedicated OCD patients (including 13 drug-naïve individuals) and 23 healthy controls. Voxel-based analysis was then performed to detect regions with significant group difference. We compared the DTI-derived parameters of 15 patients before and after 12-week Selective Serotonin Reuptake Inhibitor (SSRI) therapies. Significant differences of DTI-derived parameters were observed between OCD and healthy groups in multiple structures, mainly within the fronto-striato-thalamo-cortical loop. An increased RD in combination with no change in AD among OCD patients was found in the left medial superior frontal gyrus, temporo-parietal lobe, occipital lobe, striatum, insula and right midbrain. There was no statistical difference in DTI-derived parameters between drug-naive and previously medicated OCD patients. After being medicated, OCD patients showed a reduction in RD of the left striatum and right midbrain, and in MD of the right midbrain. CONCLUSION: Our preliminary findings suggest that abnormalities of white matter microstructure, particularly in terms of myelin integrity, are primarily located within the fronto-striato-thalamo-cortical circuit of individuals with OCD. Some abnormalities may be partly reversed by SSRI treatment

Chem. Eng. Sci.

The unsteady motion of single bubbles rising freely in a quiescent liquid with high viscosity was measured using a CCD (charge coupled device) camera. Sequences of the recorded frames were digitized and analyzed using image analysis software and the measurements of the acceleration and steady motion of bubbles were obtained. The total drag coefficient was calculated from the accelerating motion to the steady motion with the added mass force and history force included. In virtue of dimensional analysis, the total drag coefficient of single bubbles is correlated as a function of the acceleration number, Archimedes number and Reynolds number based on the equivalent bubble diameter. The proposed correlation represents very well the experimental data of the total drag force in a wide range covering both unsteady accelerating motion and steady motion. The combined added mass and history force coefficient accounting for the accelerating effect on single bubbles was evaluated and correlated. (C) 2008 Elsevier Ltd. All rights reserved.The unsteady motion of single bubbles rising freely in a quiescent liquid with high viscosity was measured using a CCD (charge coupled device) camera. Sequences of the recorded frames were digitized and analyzed using image analysis software and the measurements of the acceleration and steady motion of bubbles were obtained. The total drag coefficient was calculated from the accelerating motion to the steady motion with the added mass force and history force included. In virtue of dimensional analysis, the total drag coefficient of single bubbles is correlated as a function of the acceleration number, Archimedes number and Reynolds number based on the equivalent bubble diameter. The proposed correlation represents very well the experimental data of the total drag force in a wide range covering both unsteady accelerating motion and steady motion. The combined added mass and history force coefficient accounting for the accelerating effect on single bubbles was evaluated and correlated. (C) 2008 Elsevier Ltd. All rights reserved

Ind. Eng. Chem. Res.

The motion of a single bubble rising unsteadily and steadily in a quiescent non-Newtonian liquid was investigated experimentally. By using a charged coupled device camera to follow the rising bubble, the sequences of the recorded frames were digitized and analyzed using image analysis software, and the measurements of the acceleration and steady motion of bubbles were obtained. Using the experimental data, we proposed an empirical correlation to predict the total drag coefficient calculated from the accelerating motion to the steady motion with the added rnass force and history force included. This correlation is an extension of our previous work with non-Newtonian fluids. This new correlation represents very well the experimental data of the total drag force in a wide range covering both unsteady accelerating motion and steady motion in non-Newtonian fluids.The motion of a single bubble rising unsteadily and steadily in a quiescent non-Newtonian liquid was investigated experimentally. By using a charged coupled device camera to follow the rising bubble, the sequences of the recorded frames were digitized and analyzed using image analysis software, and the measurements of the acceleration and steady motion of bubbles were obtained. Using the experimental data, we proposed an empirical correlation to predict the total drag coefficient calculated from the accelerating motion to the steady motion with the added rnass force and history force included. This correlation is an extension of our previous work with non-Newtonian fluids. This new correlation represents very well the experimental data of the total drag force in a wide range covering both unsteady accelerating motion and steady motion in non-Newtonian fluids

Aiche J.

Both the large eddy simulation (LES) technique and the k-epsilon turbulent model were used to simulate the gas-liquid turbulent flow in a stirred tank driven by a Rushton impeller. A Eulerian-Eulerian two-fluid model for gas-liquid two-phase flow, was developed using the large eddy,v simulation for both gas (aid liquid phases. The relative baffles was accounted for through the movement of the rotating impeller to the static baffles 'improved inner-outer iterative algorithm. The spatial discretization of the governing equations was performed on a cylindrical staggered grid. For the LES, a conventional Sniagorinsky,v sub-grid model was adapted to modeling the turbulence of the liquid phase. The momentum and continuity equations were discretized using the finite diffrence method, ",ij'h a third order QUICK (Quadratic Upwind Interpolation tor Convective Kinematics) scheme used for convective terms. The phase-resolved predictions of the LES were compared with the experimental data and the simulation results by the standard k-epsilon model, suggesting that the LES has much better accuracy than the k-epsilon model. (c) 2008 American Institute of Chemical Engineers.Both the large eddy simulation (LES) technique and the k-epsilon turbulent model were used to simulate the gas-liquid turbulent flow in a stirred tank driven by a Rushton impeller. A Eulerian-Eulerian two-fluid model for gas-liquid two-phase flow, was developed using the large eddy,v simulation for both gas (aid liquid phases. The relative baffles was accounted for through the movement of the rotating impeller to the static baffles 'improved inner-outer iterative algorithm. The spatial discretization of the governing equations was performed on a cylindrical staggered grid. For the LES, a conventional Sniagorinsky,v sub-grid model was adapted to modeling the turbulence of the liquid phase. The momentum and continuity equations were discretized using the finite diffrence method, ",ij'h a third order QUICK (Quadratic Upwind Interpolation tor Convective Kinematics) scheme used for convective terms. The phase-resolved predictions of the LES were compared with the experimental data and the simulation results by the standard k-epsilon model, suggesting that the LES has much better accuracy than the k-epsilon model. (c) 2008 American Institute of Chemical Engineers