bluuebunny/crossref_metadata_2025 huggingface dataset:
Strongly Absorbing π–π* States in Heteroleptic Dipyrrin/2,2′‐Bipyridine Ruthenium Complexes: Excited‐State Dynamics from Resonance Raman Spectroscopy
Authors: McLean Tracey M. , Cleland Deidre M. , Lind Samuel J. , Gordon Keith C. , Telfer Shane G. , Waterland Mark R.
Published: July 2010

A recently reported new class of ruthenium complexes containing 2,2′‐bipyridine and a dipyrrin ligand in the coordination sphere exhibit both strong metal‐to‐ligand charge‐transfer (MLCT) and π–π* transitions. Quantitative analysis of the resonance Raman scattering intensities and absorption spectra reveals only weak electronic interactions between these states despite direct coordination of the bipyridyl and dipyrrin ligands to the central ruthenium atom. On the basis of DFT calculations and time‐dependent DFT (TD‐DFT), we propose that the electronic excited states closely resemble “pure” MLCT and π–π* states. Resonance Raman intensity analysis demonstrates that a large amplitude transannular torsional motion provides a mechanism for relaxation on the π–π* excited‐state surface. We assert that this result is generally applicable to a range of dipyrrin complexes such as boron–dipyrrin and metallodipyrrin systems. Despite the large torsional distortion between the phenyl ring and the dipyrromethene plane, π–π* excitation extends out onto the phenyl ring which may have important consequences in solar‐energy‐conversion applications of ruthenium–dipyrrin complexes.
Catalytic effect of ReAu nanoalloy on the Te particle reaction and its application to resonance scattering spectral assay of CA125
Authors: Cai Wei , Liang Aihui , Liu Qingye , Liao Xianjiu , Jiang Zhiliang , Shang Guangyi
Published: July 2010

ReAu nanoparticles with a molar ratio of 2:8 Re and Te nanoparticles were prepared by NaBH4 reduction. In HCl medium at 65°C, ultratrace Re, Te and ReAu bimetallic nanoparticles strongly catalyzed the slow reaction between Sn(II) and Te(VI) to form Te particles, which exhibited the strongest resonance scattering (RS) peak at 782 nm. As the amount of nanocatalyst increased, the RS intensity at 782 nm (I782 nm) increased linearly, and the increase in intensity ΔI782 nm was linear to the ReAu, Re and Te concentrations in the ranges 0.07–9.0, 0.01–4.5 and 30–1200 nm, respectively. As a model, a ReAu immunonanoprobe catalytic Te–particle resonance scattering spectral (RSS) method was established for detection of CA125, using ReAu nanoparticle labeling CA125 antibody (CA125Ab) to obtain an immunonanoprobe (ReAuCA125Ab) for CA125. In pH 7.6 citric acid–Na2HPO4 buffer solution, ReAuCA125Ab aggregated nonspecifically. Upon addition of CA125, the immunonanoprobe reacted with it to form ReAuCA125Ab–CA125 dispersive immunocomplex in the solution. After the centrifugation, the supernatant containing the immunocomplex was used to catalyze the reaction of Te(VI)–Sn(II) to produce the Te particles that resulted in the I782 nm increasing. The ΔI782 nm was linear to CA125 concentration (CCA125) in the range 0.1–240 mU/mL. The regression equation, correlation coefficient and detection limit were ΔI782 nm = 1.61 CCA125 + 1.5, 0.9978 and 0.02 mU/mL, respectively. The proposed method was applied to detect CA125 in serum samples, with satisfactory results. Copyright © 2010 John Wiley & Sons, Ltd.
A phase 2 trial of single‐agent bevacizumab given in an every‐3‐week schedule for patients with recurrent high‐grade gliomas
Authors: Raizer Jeffrey J. , Grimm Sean , Chamberlain Marc C. , Nicholas M. Kelly , Chandler James P. , Muro Kenji , Dubner Steven , Rademaker Alfred W. , Renfrow Jaclyn , Bredel Markus
Published: July 2010

BACKGROUND:

The authors evaluated a 3‐week schedule of bevacizumab in patients with recurrent high‐grade glioma (HGG).

METHODS:

Patients received bevacizumab 15 mg/kg every 3 weeks and were evaluated every 6 weeks until tumor progression. Tissue correlates were used to quantify tumor content of vascular endothelial growth factor A (VEGFA) and vascular endothelial growth factor receptor‐2 (VEGFR2).

RESULTS:

Of 61 patients who were treated (35 men and 26 women; median age, 52 years; age range, 21‐78 years), 50 patients had glioblastoma multiforme (GBM), and 11 patients had anaplastic glioma (AG). The median number of previous chemotherapies was 2 (range, 1‐5 previous chemotherapies), and 16 patients had received ≥3 previous chemotherapies. The median number of bevacizumab doses was 4 (range, 1‐20 doses), and 45% of patients received >5 doses. The toxicities observed were primarily grade 1 and 2, and the most common were fatigue, hypertension, and headache. One grade 2 intratumoral bleed and 1 bowel perforation were reported. For patients with GBM, the 6‐month progression‐free survival rate was 25%, the median time to tumor progression was 10.8 weeks, and the median overall survival was 25.6 weeks. The best response included a partial response in 15 patients (24.5%) and stable disease in 31 patients (50.8%) patients; radiographic recurrence patterns included increased changes in fluid attenuation inversion recovery (24%) and multifocal recurrence (20%). The median survival after bevacizumab failure was 10 weeks. The ratio of tumor VEGFA/VEGFR2 was increased in patients aged >55 years; an increased VEGFA/VEGFR2 ratio was correlated nonsignificantly with decreased survival (P = .052).

CONCLUSIONS:

An every‐3‐week schedule of bevacizumab had antitumor activity and was relatively nontoxic for patients with recurrent HGG. The predictive value of VEGFA/VEGFR2 in tumor will require validation in a larger patient cohort. Cancer 2010. © 2010 American Cancer Society.
Phase 1 trial of bortezomib plus R‐CHOP in previously untreated patients with aggressive non‐Hodgkin lymphoma
Authors: Furman Richard R. , Martin Peter , Ruan Jia , Cheung Ying‐Kuen K. , Vose Julie M. , LaCasce Ann S. , Elstrom Rebecca , Coleman Morton , Leonard John P.
Published: July 2010

BACKGROUND:

Bortezomib has preclinical and clinical in B‐cell lymphomas, both alone and in combination with other agents. A phase 1 evaluation was conducted of bortezomib with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R‐CHOP) in patients with untreated diffuse large B‐cell lymphoma (DLBCL) or mantle cell lymphoma (MCL).

METHODS:

Twenty patients (16 with DLBCL and 4 with MCL) with a median age of 66 years (range, 29‐84 years) were enrolled. Eleven subjects (55%) had an elevated lactate dehydrogenase level, and 10 patients (50%) had International Prognostic Index scores of 3 to 5. Standard R‐CHOP was administered on a 21‐day cycle for 6 cycles, with 1 of 3 dose levels of bortezomib (0.7 mg/m2 [n = 4 patients], 1.0 mg/m2 [n = 9 patients], or 1.3 mg/m2 [n = 7 patients]) administered on Days 1 and 4 of each cycle.

RESULTS:

The maximum tolerated dose of bortezomib with R‐CHOP was not reached, and the 1.3‐mg/m2 dose level had acceptable tolerability. A dose‐limiting toxicity (pulmonary) was only observed in 1 patient receiving 1.0 mg/m2 of bortezomib. Neuropathy occurred in 13 patients (65%), but was mostly grade 1 (45%) and reached grade 3 in only 1 patient (all toxicities were graded using the Common Terminology Criteria for Adverse Events, version 3.0). Grade 4 hematologic toxicity occurred in 7 patients (35%). Of 19 evaluable patients, all responded, with 18 (95%) cases of complete response/complete response unconfirmed achieved and 1 (5%) partial response reported. At a median follow‐up of 56 months, overall survival at 4 years was 75% and progression‐free survival was 58%.

CONCLUSIONS:

Bortezomib at a dose of 1.3 mg/m2 twice per cycle can be added to R‐CHOP chemotherapy with acceptable toxicity. Multi‐institutional and cooperative group follow‐up studies of this regimen are currently ongoing. Cancer 2010. © 2010 American Cancer Society.
Investigation of Turbulent Transport and Shear Flows in the Edge of Toroidal Plasmas
Authors: Ramisch M. , Birkenmeier G. , Happel T. , Köhn A. , Mahdizadeh N. , Manz P. , Nold B. , Wilcox R. , Anderson D. T. , Stroth U.
Published: July 2010

Intense Langmuir‐probe measurements were carried out in the toroidal low‐temperature plasma of the torsatron TJ‐K in order to investigate the origin and dynamics of intermittent transport events, so‐called blobs, at the transition from closed to open field lines. The statistical properties of the fluctuations at the plasma boundary agree with observations made in fusion edge plasmas. Blobs were found to be generated locally through a change in turbulence drive across the separatrix. The non‐linear spectral energy transfer from small‐scale fluctuations into large‐scale flows was measured with a 128‐probe array. The results point to the transfer being a key loss channel for turbulence energy leading to a reduction in turbulent transport. Earlier observations [M.A. Pedrosa et al., Phys. Rev. Lett. 100, 215003 (2008)] of enhanced long‐range correlations in the plasma potential through externally induced shear flows in TJ‐II stellarator were verified. The newly measured correlation of zonal vorticity and Reynolds stress at induced flow shear indicates an enhancement of zonal‐flow drive (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Motional Stark Effect Spectra Simulations for Wendelstein 7‐X
Authors: Reimer R. , Dinklage A. , Geiger J. , Hobirk J. , Reich M. , Wolf R. , ASDEX Upgrade  , Wendelstein 7‐X Teams
Published: July 2010

Simulations of motional Stark effect (MSE) spectra for Wendelstein 7‐X (W7‐X) are reported. While contributing to experimental equilibrium reconstruction in general, the measurements aim at the detection of small deviations of vacuum fields, such as the diamagnetic effect. For the diagnostic beam on W7‐X, the expected plasma β implies a diamagnetic effect as low as 3%. A data model for the measurement has been developed for the application to W7‐X. The model includes polarisation effects and the beam attenuation to estimate the required signal dynamics. The model has been applied to ASDEX Upgrade data (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Overview of Experimental Results from the WEGA Stellarator
Authors: Otte M. , Laqua H.P. , Chlechowitz E. , Drewelow P. , Glaubitz M. , Marsen S. , Müller E. , Podoba Y. , Schacht J. , Stange T. , Steffen F. , Wagner F. , Wolf R. , Zhang D.
Published: July 2010

A progress report on recent experiments in the WEGA stellarator is given dedicated to diagnostic development – especially for the 0.5 T operation of 28 GHz ECR heated plasmas – and magnetic field line visualization experiments in the vacuum field. Furthermore, results from transport and turbulence studies in the plasma edge and first measurements inside magnetic islands are presented with the help of 1D and 2D Langmuir probe arrays. Additionally, the prototype installation of the Wendelstein 7‐X control system is under continuous tests and further development at WEGA (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Flow Velocity Measurements Using ChERS in the HSX Stellarator
Authors: Briesemeister A. , Zhai K. , Anderson D. T. , Anderson F.S. B. , Lore J. , Talmadge J. N.
Published: July 2010

A Charge Exchange Recombination Spectroscopy (ChERS) system has been used to measure the velocity, density, and temperature profiles of fully stripped carbon impurities in the Helically Symmetric eXperiment (HSX). Velocity measurements have been obtained by reversing the magnetic field between sets of shots in order to reverse the plasma flow velocity. This essentially doubles the Doppler shift of the measured photons. It also eliminates the need to accurately determine the exact wavelength of the unshifted emission line which can depend on plasma conditions. Because two viewing angles are used for each radial location, the velocity magnitude and direction can be determined. The intrinsic velocity is found to move primarily in the direction of quasihelical symmetry with a peak velocity ∼20 km/s. The velocity increases with increasing ECRH power (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Equilibrium and Stability of Current‐Carrying Discharges in the Non‐Axisymmetric CTH Experiment
Authors: Hanson J. D. , Knowlton S. F. , Stevenson B. A. , Hartwell G. J.
Published: July 2010

Detailed knowledge of the experimental plasma equilibrium is becoming as important for stellarators as it is for tokamaks, but reconstruction of magnetic flux surfaces from magnetic measurements is more difficult in the three‐dimensional geometry of stellarators than in axisymmetric configurations. We report the first reconstructions of experimental stellarator equilibria with the V3FIT [1] code. We also introduce the signal effectiveness, and describe initial studies of density‐driven disruption in current‐carrying stellarator plasmas. At low vacuum transform, disruptions can be triggered at a plasma density comparable to the Greenwald limit, but disruption signatures disappear as the vacuum rotational transform is raised above 0.1 (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energetic‐Particle‐Driven Instabilities in General Toroidal Configurations
Authors: Spong D.A. , Breizman B.N. , Brower D.L. , D'Azevedo E. , Deng C.B. , Konies A. , Todo Y. , Toi K.
Published: July 2010

Energetic‐particle driven instabilities have been extensively observed in both tokamaks and stellarators. In order for such devices to ultimately succeed as D‐T fusion reactors, the super‐Alfvénic 3.5 Mev fusion‐produced alpha particles must be sufficiently well confined. This requires the evaluation of losses from classical collisional transport processes as well as from energetic particle‐driven instabilities. An important group of instabilities in this context are the discrete shear Alfvén modes, which can readily be destabilized by energetic particles (with velocities of the order of vAlfvén) through wave‐particle resonances. While these modes in three‐dimensional systems have many similarities to those in tokamaks, the detailed implementation of modeling tools has required development of new methods. Recent efforts in this direction will be described here, with an emphasis on reduced models (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Drift Stabilisation of Ballooning Modes in an Inward‐Shifted LHD Configuration
Authors: Cooper W. A. , Brocher L. , Graves J. P. , Cooper G. A. , Narushima Y. , Watanabe K. Y.
Published: July 2010

A drift‐magnetohydrodynamic theory is applied to a background anisotropic pressure equilibrium state to generate a drift corrected ballooning mode equation. The ratio of the mode frequency to the hot particle drift frequency constitutes the critical expansion parameter. The fast particles thus contribute weakly to the instability driving mechanism and also to the diamagnetic drift stabilisation. This equation is used to model the inward‐shifted Large Helical Device (LHD) configuration. In the single‐fluid limit, a weakly ballooning unstable band that encompasses a third of the plasma volume develops in the core of the plasma at low 〈βdia 〉 that becomes displaced towards the edge of the plasma at the experimentally achieved 〈βdia 〉 ≃ 5%. Finite diamagnetic drifts (mainly due to the thermal ions) effectively stabilise these ballooning structures at all values of 〈βdia 〉. The validity of the large hot particle drift approximation is verified for hot to thermal ion density ratios that remain smaller than 2% (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mononuclear Copper(I) Complexes Containing Redox‐Active 1,2‐Bis(aryl‐imino)acenaphthene Acceptor Ligands: Synthesis, Crystal Structures and Tuneable Electronic Properties
Authors: Kern Thomas , Monkowius Uwe , Zabel Manfred , Knör Günther
Published: July 2010

A series of pseudo‐tetrahedral copper(I) complexes carrying bis(imino)acenaphthene (BIAN) ligands as acceptor subunits and various phosphane derivatives was prepared and characterized by elemental analysis, X‐ray crystallography and spectroscopic techniques. The electronic spectra of the compounds are dominated by low‐lying metal‐to‐ligand charge transfer (MLCT) transitions which could be systematically modified by different substituent patterns at the diimine acceptor subunit and by variations of the electron donating properties and bite angles of the phosphane moiety. A qualitative model based on frontier‐orbital overlap arguments is introduced to describe the observed variations in optical spectra, excited state energies, solvatochromic behaviour, charge transfer character, and extent of electronic coupling following moderate changes in orbital mixing. Due to their readily tuneable properties and the potential of the BIAN ligands to reversibly store up to four redox equivalents, these systems are of considerable interest for the development of novel multi‐electron transfer photosensitizers which are based on the abundant and environmentally benign transition metal copper.
Synthesis of Functionalized Triazatriangulenes for Application in Photo‐Switchable Self‐Assembled Monolayers
Authors: Kubitschke Jens , Näther Christian , Herges Rainer
Published: July 2010

Various triazatriangulenes are synthesized by nucleophilic attack at the central C atom of triazatriangulenium ions. The molecular functions, especially azobenzenes, are fixed via an ethynyl linker by in situ deprotection of trimethylsilylalkynes. The structure of two of these molecules is further investigated by X‐ray crystallography. The photo‐induced trans/cis‐isomerization of the azobenzene substituted derivatives is analyzed in solution and shows great promise for the preparation of switchable functionalized monolayers, as the triazatriangulenes are known for their self‐assembly on gold surfaces.1
Water‐Soluble Palladium Nanoparticles: Click Synthesis and Applications as a Recyclable Catalyst in Suzuki Cross‐Couplings in Aqueous Media
Authors: Mejías Nereida , Pleixats Roser , Shafir Alexandr , Medio‐Simón Mercedes , Asensio Gregorio
Published: July 2010

A new PEG‐tagged material, which was prepared by a threefold copper‐catalyzed [3+2] cycloaddition (click chemistry), was found to act as an efficient stabilizer for palladium nanoparticles. The newly formed material proved to be active as a recyclable catalyst in Suzuki coupling; the presence of polyether chains allowed for the catalytic runs to be conducted in aqueous media.
Covalent Bonds on Activated Carbon
Authors: López de la Torre M. Dolores , Melguizo Guijarro Manuel
Published: July 2010

This microreview presents a concise overview of the different synthetic approaches that have been applied to activated carbons over the years, with particular attention paid to the most recent contributions to achieving stable covalent linkage on their surfaces. The method of choice for covalent immobilization of molecules on carbon surfaces has been the creation of functional groups such as carboxylic acid, acyl halide, lactone and hydroxy groups on a surface through chemical reactions. The molecules or fragments of choice to be introduced are then tethered or covalently anchored to the reactive surface.
Abnormal regional spontaneous neural activity in treatment‐refractory depression revealed by resting‐state fMRI
Authors: Wu Qi‐Zhu , Li Dong‐Ming , Kuang Wei‐Hong , Zhang Ti‐Jiang , Lui Su , Huang Xiao‐Qi , Chan Raymond C.K. , Kemp Graham J. , Gong Qi‐Yong
Published: July 2010

Treatment‐refractory depression (TRD) represents a large proportion of the depressive population, yet has seldom been investigated using advanced imaging techniques. To characterize brain dysfunction in TRD, we performed resting‐state functional MRI (rs‐fMRI) on 22 TRD patients, along with 26 matched healthy subjects and 22 patients who were depressed but not treatment‐refractory (NDD) as comparison groups. Results were analyzed using a data‐driven approach known as Regional Homogeneity (ReHo) analysis which measures the synchronization of spontaneous fMRI signal oscillations within spatially neighboring voxels. Relative to healthy controls, both depressed groups showed high ReHo primarily within temporo‐limbic structures, and more widespread low ReHo in frontal, parietal, posterior fusiform cortices, and caudate. TRD patients showed more cerebral regions with altered ReHo than did NDD. Moderate but significant correlations between the altered regional ReHo and measures of clinical severity were observed in some identified clusters. These findings shed light on the pathophysiological mechanisms underlying TRD and demonstrate the feasibility of using ReHo as a research and clinical tool to monitor persistent cerebral dysfunction in depression, although further work is necessary to compare different measures of brain function to elucidate the neural substrates of these ReHo abnormalities. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
Pharyngoesophageal diverticulum resembling a thyroid nodule on ultrasound
Authors: Singaporewalla Reyaz M. , Mukherjee Jagat J. , Thamboo Thomas P. , Cheah Wei K.
Published: July 2010

Background

Ultrasound is routinely used in evaluating thyroid nodules and performing fine‐needle aspiration cytology (FNAC). Occasionally, nonthyroidal lesions can mimic thyroid nodules on imaging and get wrongly aspirated.

Methods

A 63‐year‐old woman was reported to have an incidental left thyroid “nodule” on neck ultrasound scan. It was isoechoic with a surrounding hypoechoic rim and contained tiny foci of echogenicity. Similar findings were noted in a second surgeon‐performed ultrasound scan.

Results

An ultrasound‐guided FNAC showed abundant squamous cells, bacteria, and vegetable cells with no evidence of thyroid cells or colloid. The suspicion of a pharyngoesophageal diverticulum was confirmed on barium swallow. She remained asymptomatic with no increase in size at 6 months follow‐up.

Conclusion

A pharyngoesophageal diverticulum can be mistaken for a posteriorly placed “thyroid nodule” on ultrasound scan if the subtle differentiating signs are missed. An awareness of this condition is important to avoid unnecessary needle biopsies. © 2010 Wiley Periodicals, Inc. Head Neck, 2010
A novel biomimetic composite scaffold hybridized with mesenchymal stem cells in repair of rat bone defects models
Authors: Xu Caixia , Su Peiqiang , Wang Yingjun , Chen Xiaofeng , Meng Yongchun , Liu Chang , Yu Xinbing , Yang Xuhui , Yu Weihua , Zhang Xiuming , Xiang Andy Peng
Published: July 2010

In this study, thein vivobone‐regenerative potential of a novel bioactive glass‐collagen‐hyaluronic acid‐Phosphatidylserine (BG‐COL‐HYA‐PS) composite scaffold hybridized with mesenchymal stem cells (MSCs) was investigated in a rat bone defect model. HrGFP‐labeled MSCs were cultured for 2 weeks on the BG‐COL‐HYA‐PS scaffold before implantation into the defect. A cell‐free scaffold and an untreated defect were used as controls. The regeneration process was evaluated by histology, X‐ray, and mechanical rigidity experiments at different time points post‐implantation. The results revealed that BG‐COL‐HYA‐PS scaffold exhibited a low inflammatory response and foreign body response within 3 weeks. At week 6, those responses disappeared following the resorption of scaffolds and the formation of new bone. Compared with the pure scaffold or empty group, the introduction of MSCs into the porous scaffold dramatically enhanced the efficiency of the new bone formation and biomechanical property of the femur. In addition, the transplanted MSCs could survive for up to 3 weeks or longer. The results demonstrated that the BG‐COL‐HYA‐PS scaffold was biocompatible and osteoconductive and the transplanted MSCs with the scaffold enhanced the healing of the bone defect. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
pH effect on the synthesis, shear properties, and homogeneity of iron‐crosslinked hyaluronic acid‐based gel/adhesion barrier
Authors: Isayeva Irada , Sarkar Das Srilekha , Chang Andrew , DeFoe Jacqueline , Luu Hoan‐My Do , Vorvolakos Katherine , Patwardhan Dinesh , Whang Joyce , Pollack Steven
Published: July 2010

Iron‐crosslinked hyaluronic acid hydrogel (FeHA) has been used to reduce postsurgical adhesions in patients undergoing open, gynecological surgery. The performance of FeHA gel as an adhesion barrier device is influenced by many factors, including the physicochemical gel properties, which, in turn, depend on the chemistry and conditions of the device manufacturing. In this work, we demonstrate the effect of reaction pH on rheology and homogeneity of FeHA gels formulated in house and also compare the viscoelastic properties of FeHA gels with that of uncrosslinked HA solution of similar HA concentration and ionic strength. Dynamic mechanical analyses provide evidence that the reaction of HA with Fe(III) ions leads to the formation of “weak” gels. The viscoelastic properties and homogeneity of FeHA gels vary depending on the pH at which crosslinking was initiated. When solution pH, at the start of crosslinking, varied between 1.5 and 3, the low‐shear rate viscosity of FeHA varied between 10,000 and 40,000 cPoise (10–40 Pa s). The highest steady‐state shear viscosity and viscoelasticity were measured when pH was around 2.6, which is similar to the pH‐dependent viscoelasticity of pure HA solution. Initiating HA crosslinking at pH ≤ 3 led to relatively homogenous solutions, while crosslinking higher pH > 3 caused instantaneous gel precipitation and inhomogeneities. Sensitivity of FeHA gel properties to small variations in reaction pH clearly supports the need for a tight manufacturing control during medical device fabrication. © 2010 Wiley Periodicals, Inc.* J Biomed Mater Res Part B: Appl Biomater, 2010.
Chondro/osteoblastic and cardiovascular gene modulation in human artery smooth muscle cells that calcify in the presence of phosphate and calcitriol or paricalcitol
Authors: Shalhoub V. , Shatzen E.M. , Ward S.C. , Young J‐I. , Boedigheimer M. , Twehues L. , McNinch J. , Scully S. , Twomey B. , Baker D. , Kiaei P. , Damore M.A. , Pan Z. , Haas K. , Martin D.
Published: July 2010

Vitamin D sterol administration, a traditional treatment for secondary hyperparathyroidism, may increase serum calcium and phosphorus, and has been associated with increased vascular calcification (VC). In vitro studies suggest that in the presence of uremic concentrations of phosphorus, vitamin D sterols regulate gene expression associated with trans‐differentiation of smooth muscle cells (SMCs) to a chondro/osteoblastic cell type. This study examined effects of vitamin D sterols on gene expression profiles associated with phosphate‐enhanced human coronary artery SMC (CASMC) calcification. Cultured CASMCs were exposed to phosphate‐containing differentiation medium (DM) with and without calcitriol, paricalcitol, or the calcimimetic R‐568 (10−11–10−7 M) for 7 days. Calcification of CASMCs, determined using colorimetry following acid extraction, was dose dependently increased (1.6‐ to 1.9‐fold) by vitamin D sterols + DM. In contrast, R‐568 did not increase calcification. Microarray analysis demonstrated that, compared with DM, calcitriol (10−8 M) + DM or paricalcitol (10−8 M) + DM similarly and significantly (P < 0.05) regulated genes of various pathways including: metabolism, CYP24A1; mineralization, ENPP1; apoptosis, GIP3; osteo/chondrogenesis, OPG, TGFB2, Dkk1, BMP4, BMP6; cardiovascular, HGF, DSP1, TNC; cell cycle, MAPK13; and ion channels, SLC22A3 KCNK3. R‐568 had no effect on CASMC gene expression. Thus, SMC calcification observed in response to vitamin D sterol + DM may be partially mediated through targeting mineralization, apoptotic, osteo/chondrocytic, and cardiovascular pathway genes, although some gene changes may protect against calcification. Further studies to determine precise roles of these genes in development of, or protection against VC and cardiovascular disease are required. J. Cell. Biochem. 111: 911–921, 2010. © 2010 Wiley‐Liss, Inc.
Oxidative stress enhances AP‐1 and NF‐κB‐mediated regulation of β2‐Glycoprotein I gene expression in hepatoma cells
Authors: Chiu Wen‐Chin , Chen Chun‐Jung , Lee Tzong‐Shyuan , Chen Zit‐Jie , Ke Pei‐Hsin , Chiang An‐Na
Published: July 2010

β2‐Glycoprotein I (β2‐GPI), also known as apolipoprotein H, is a plasma glycoprotein with poorly defined gene regulation. The aim of this study was to clarify the role of oxidative stress in β2‐GPI gene regulation and determine the essential transcription element regulating β2‐GPI expression. We demonstrate that expression of β2‐GPI at the protein and mRNA levels was significantly elevated in Huh7 and HepG2 cells treated with 100 µM hydrogen peroxide (H2O2). To address the transcriptional mechanism of H2O2‐mediated β2‐GPI gene regulation, several promoter constructs were cloned and characterized by deletion assays. A region spanning from −2141 to −1419 (relative to the transcription start site), which contains two activator protein‐1 (AP‐1) sites (AP1‐2 and AP1‐3) and one nuclear factor‐kappaB (NF‐κB) site was found to be the main target site for up‐regulation of β2‐GPI promoter activity by oxidative stress. In addition, we found that H2O2 stimulation enhanced the nuclear translocation of AP‐1 and NF‐κB subunits. Using an electrophoretic mobility shift assay, it was confirmed that nuclear protein binding to the AP1‐2, AP1‐3, and NF‐κB sites was increased in Huh7 cells treated with H2O2. Knockdown of the c‐Jun, c‐Fos, p65, and p50 genes using small interfering RNAs (siRNAs) further confirmed that AP‐1 and NF‐κB play an essential role in the H2O2‐induced β2‐GPI expression. Overall, these findings provide new insight suggesting that multiple cis‐elements in the β2‐GPI promoter work cooperatively to regulate β2‐GPI expression in cells under oxidative stress. J. Cell. Biochem. 111: 988–998, 2010. © 2010 Wiley‐Liss, Inc.
Mesenchymal stem cells inhibit both endogenous and exogenous MMPs via secreted TIMPs
Authors: Lozito Thomas P. , Tuan Rocky S.
Published: July 2010

Mesenchymal stem cells (MSCs) have been shown to be perivascular, occupying a prime location for regulating vessel stability. Here, we focused on the MSC‐contribution of key regulators of the perivascular niche, the matrix metalloproteinases (MMPs) and their inhibitors, the TIMPs. Despite secretion of active forms of MMPs by MSCs, MMP enzyme activity was not detected in MSC‐conditioned medium (MSC‐CM) due to TIMP‐mediated inhibition. By means of bifunctional‐crosslinking to probe endogenous MMP:TIMP interactions, we showed MMP‐2‐inhibition by TIMP‐2. MSCs also inhibited high levels of exogenous MMP‐2 and MMP‐9 through TIMP‐2 and TIMP‐1, respectively. Furthermore, MSC‐CM protected vascular matrix molecules and endothelial cell structures from MMP‐induced disruption. MSCs remained matrix‐protective when exposed to pro‐inflammatory cytokines and hypoxia, countering these stresses with increased TIMP‐1 expression and augmented MMP‐inhibition. Thus, MSCs are revealed as robust sources of TIMP‐mediated MMP‐inhibition, capable of protecting the perivascular niche from high levels of MMPs even under pathological conditions. J. Cell. Physiol. 226: 385–396, 2011. © 2010 Wiley‐Liss, Inc.
Effects of urbanization and climate change on surface runoff of the Brussels Capital Region: a case study using an urban soil–vegetation–atmosphere‐transfer model
Authors: Hamdi Rafiq , Termonia Piet , Baguis Pierre
Published: July 2010

This study describes the use of a state‐of‐the‐art urban parameterization (the Town Energy Balance scheme, TEB) to examine how the surface runoff of the Brussels Capital Region (BCR) responded to historical urbanization (1960–1999) and how it will respond in cases of climate changes and/or future urbanization. Key for this study is that both energy and water balances are resolved and interact through the evaporative term. Historical urbanization of BCR is estimated from changes in impervious surface area using remote sensing imagery and future climate is modelled using data from two members of the European project PRUDENCE. Results show that (1) a change could be detected in the annual series of cumulative surface runoff, high flow and the frequency of flood events when imperviousness exceeds 35%. (2) Climate change has a greater impact on low flows than urbanization. (3) In terms of high flow and annual cumulative runoff, historical urbanization and the precipitation increase scenario have approximately the same increasing trend. However, during summertime when floods happen frequently in the BCR, the average contribution of urbanization is four times greater than that due to the increase in precipitation in terms of the cumulative runoff ratio. (4) The assumed 10% increase in imperviousness in the BCR is able to counteract the increase in evapotranspiration due to warmer climate predictions. (5) When combining the effect of future urbanization (+20% of imperviousness) and precipitation scenario together, the increase in high flow is exacerbated. Copyright © 2010 Royal Meteorological Society
Structure–retention relationship study of arylpiperazines by linear multivariate modeling
Authors: Trifković Jelena , Andrić Filip , Ristivojević Petar , Andrić Deana , Tešić Živoslav Lj , Milojković‐Opsenica Dušanka M.
Published: July 2010

A quantitative structure–retention relationship study has been performed to correlate the retention of 33 newly synthesized arylpiperazines with their molecular characteristics, using thin‐layer chromatography. Principal component analysis followed by multiple linear regression (MLR), principal component regression (PCR) and partial least squares (PLS) was performed to identify the most important factors, to quantify their influences, and to select descriptors that best describe the behavior of the compounds investigated. The best statistical performance was achieved by applying PLS regression, leading to the lowest value of the standard error (root mean square errors of calibration of 0.159 and cross‐validated value RMSE cross‐validation=0.231 units), followed by the PCR (root mean square errors of calibration=0.195 and RMSE cross‐validation=0.305) and MLR ($R_{{\rm{adj}}}^2$=0.9499, F=102.017, mean square error=0.052 and predicted residual error sum of squares=2.23). Two factors of the highest influence: surface tension and hydrophilic–lipophilic balance appear as the part of obtained models. In addition, polar surface area and hydrophilic surface area are included by both PLS and PCR models. Moreover, logP has been added to the PLS model. Besides, PCR model includes following descriptors: hydrogen bond acceptor, hydrogen bond donor and LUMO energy, whereas topological descriptors: connectivity indices 0 and 2, and valence index 3 are included in the MLR model.
Synthesis and application of core‐shell complex‐imprinted polymer for the solid‐phase extraction of melamine from dairy products
Authors: Zhang Zhaohui , Zhang Minglei , Luo Lijuan , Yang Xiao , Hu Yufang , Zhang Huabin , Yao Shouzhuo
Published: July 2010

A core‐shell complex‐imprinted polymer (CIP) was synthesized and evaluated for selective extraction of melamine from dairy products. The CIP synthesis based on surface modification of home‐made silicon microspheres was conductedviaa metal complex as functional monomer, ethylene glycol dimethylacrylate as cross‐link and melamine as template. The resulting CIP was characterized by SEM and Fourier transform infrared spectroscopy. When the amount of silica microspheres was 100 mg and the molar ratio of copper(II) methacrylate to EDGMA was 1:10, well‐dispersed particles were obtained. The complex‐imprinted SPE condition was optimized and the maximum enrichment factor of melamine can be up to 40. The reliability of complex‐imprinted SPE for extraction and enrichment of melamine was investigated and proved by using spiked samples including milk and milk powder with the recoveries ranging from 87 to 92%.
Phonon dynamics simulation of TlH2PO4 crystal
Authors: Shchur Yaroslav
Published: July 2010

Lattice dynamics of TlH2PO4 crystal was simulated within the atomistic semi‐empirical approach in high‐temperature Pbcn and ferroelastic P21/b phases. Phonon dispersion relations, partial density of phonon states, dispersion of mean square displacements and isotropic temperature factors were calculated. Using both the lattice dynamics simulation and phenomenological Landau–Ginzburg analysis it was shown that the ferroelastic phase transition occurs due to the bilinear interaction between the soft B3g optical and transverse acoustic TAYZ phonon modes. The oxygen–hydrogen interactions within the shorter O1H1···O2 hydrogen bonds play the key role at the ferroelastic phase transition.
Nanopatch‐Targeted Skin Vaccination against West Nile Virus and Chikungunya Virus in Mice
Authors: Prow Tarl W. , Chen Xianfeng , Prow Natalie A. , Fernando Germain J. P. , Tan Cindy S. E. , Raphael Anthony P. , Chang David , Ruutu Merja P. , Jenkins Derek W. K. , Pyke Alyssa , Crichton Michael L. , Raphaelli Kristin , Goh Lucas Y. H. , Frazer Ian H. , Roberts Michael S. , Gardner Joy , Khromykh Alexander A. , Suhrbier Andreas , Hall Roy A. , Kendall Mark A. F.
Published: July 2010

The ‘Nanopatch’ (NP) comprises arrays of densely packed projections with a defined geometry and distribution designed to physically target vaccines directly to thousands of epidermal and dermal antigen presenting cells (APCs). These miniaturized arrays are two orders of magnitude smaller than standard needles—which deliver most vaccines—and are also much smaller than current microneedle arrays. The NP is dry‐coated with antigen, adjuvant, and/or DNA payloads. After the NP was pressed onto mouse skin, a protein payload co‐localized with 91.4 ± 4.1 APC mm−2 (or 2925 in total) representing 52% of the delivery sites within the NP contact area, agreeing well with a probability‐based model used to guide the device design; it then substantially increases as the antigen diffuses in the skin to many more cells. APC co‐localizing with protein payloads rapidly disappears from the application area, suggesting APC migration. The NP also delivers DNA payloads leading to cutaneous expression of encoded proteins within 24 h. The efficiency of NP immunization is demonstrated using an inactivated whole chikungunya virus vaccine and a DNA‐delivered attenuated West Nile virus vaccine. The NP thus offers a needle‐free, versatile, highly effective vaccine delivery system that is potentially inexpensive and simple to use.
Radiological research activity 1998–2007: relationship to gross domestic product, health expenditure and public expenditure on education
Authors: Spitzmueller David , Hodler Juerg , Seifert Burkhardt , Zanetti Marco
Published: July 2010

Objective

The purpose of this study was to evaluate the relationship of the radiological research activity from 1998 to 2007 to the gross domestic product (GDP), health expenditure and public expenditure on education.

Methods

The population-adjusted research activity determined by the number of articles published, the cumulative impact factor (IF) and the cumulative IF per capita were correlated with per capita values of the GDP, health expenditure and public education expenditure. Linear regression analysis and multiple regression analysis were used for statistical analysis.

Results

The cumulative IF per capita correlated with the GDP per capita (R = 0.94, P < 0.0001), health expenditure per capita (R = 0.93, P < 0.0001) and public expenditure on education per capita (R = 0.93, P < 0.0001). Multiple regression analysis demonstrated that public expenditure on education was an independent predictor of radiological research activity (P < 0.001), whereas the year, GDP and health expenditure did not reach statistical significance (P > 0.05).

Conclusion

Radiological research activity demonstrates a close relationship to the GDP, health expenditure and public expenditure on education. The last factor independently predicts research activity.
Non-spherical bubble dynamics in a compressible liquid. Part 1. Travelling acoustic wave
Authors: WANG Q. X. , BLAKE J. R.
Published: July 2010

Micro-cavitation bubbles generated by ultrasound have wide and important applications in medical ultrasonics and sonochemistry. An approximate theory is developed for nonlinear and non-spherical bubbles in a compressible liquid by using the method of matched asymptotic expansions. The perturbation is performed to the second order in terms of a small parameter, the bubble-wall Mach number. The inner flow near the bubble can be approximated as incompressible at the first and second orders, leading to the use of Laplace's equation, whereas the outer flow far away from the bubble can be described by the linear wave equation, also for the first and second orders. Matching between the two expansions provides the model for the non-spherical bubble behaviour in a compressible fluid. A numerical model using the mixed Eulerian–Lagrangian method and a modified boundary integral method is used to obtain the evolving bubble shapes. The primary advantage of this method is its computational efficiency over using the wave equation throughout the fluid domain. The numerical model is validated against the Keller–Herring equation for spherical bubbles in weakly compressible liquids with excellent agreement being obtained for the bubble radius evolution up to the fourth oscillation. Numerical analyses are further performed for non-spherical oscillating acoustic bubbles. Bubble evolution and jet formation are simulated. Outputs also include the bubble volume, bubble displacement, Kelvin impulse and liquid jet tip velocity. Bubble behaviour is studied in terms of the wave frequency and amplitude. Particular attention is paid to the conditions if/when the bubble jet is formed and when the bubble becomes multiply connected, often forming a toroidal bubble. When subjected to a weak acoustic wave, bubble jets may develop at the two poles of the bubble surface after several cycles of oscillations. A resonant phenomenon occurs when the wave frequency is equal to the natural oscillation frequency of the bubble. When subjected to a strong acoustic wave, a vigorous liquid jet develops along the direction of wave propagation in only a few cycles of the acoustic wave.
Sahara Slide: Age, initiation, and processes of a giant submarine slide
Authors: Georgiopoulou Aggeliki , Masson Douglas G. , Wynn Russell B. , Krastel Sebastian
Published: July 2010

The Sahara Slide is a giant submarine landslide on the northwest African continental margin. The landslide is located on the open continental slope offshore arid Western Sahara, with a headwall at a water depth of ∼2000 m. High primary productivity in surface waters drives accumulation of thick fine‐grained pelagic/hemipelagic sediment sequences in the slide source area. Rare but large‐scale slope failures, such as the Sahara Slide that remobilized approximately 600 km3 of sediment, are characteristic of this sedimentological setting. Seismic profiles collected from the slide scar reveal a stepped profile with two 100 m high headwalls, suggesting that the slide occurred retrogressively as a slab‐type failure. Sediment cores recovered from the slide deposit provide new insights into the process by which the slide eroded and entrained a volcaniclastic sand layer. When this layer was entrained at the base of the slide it became fluidized and resulted in low apparent friction, facilitating the exceptionally long runout of ∼900 km. The slide location appears to be controlled by the buried headwall of an older slope failure, and we suggest that the cause of the slide relates to differential sedimentation rates and compaction across these scarps, leading to local increases of pore pressure. Sediment cores yield a date of 50–60 ka for the main slide event, a period of global sea level rise which may have contributed to pore pressure buildup. The link with sea level rising is consistent with other submarine landslides on this margin, drawing attention to this potential hazard during global warming.
Homomeric protein complexes: evolution and assembly
Authors: Venkatakrishnan A.J. , Levy Emmanuel D. , Teichmann Sarah A.
Published: July 2010

Homo-oligomeric protein complexes are functionally vital and highly abundant in living cells. In the present article, we review our current understanding of their geometry and evolution, including aspects of the symmetry of these complexes and their interaction interfaces. Also, we briefly discuss the pathway of their assembly in solution.
Unravelling protein–protein interactions between complement factor H and C-reactive protein using a multidisciplinary strategy
Authors: Perkins Stephen J. , Okemefuna Azubuike I. , Nan Ruodan
Published: July 2010

Experimental studies of protein–protein interactions are very much affected by whether the complexes are fully formed (strong, with nanomolar dissociation constants) or partially dissociated (weak, with micromolar dissociation constants). The functions of the complement proteins of innate immunity are governed by the weak interactions between the activated proteins and their regulators. Complement is effective in attacking pathogens, but not the human host, and imbalances in this process can lead to disease conditions. The inherent complexity in analysing complement interactions is augmented by the multivalency of its main regulator, CFH (complement factor H), for its physiological or pathophysiological ligands. The unravelling of such weak protein–protein or protein–ligand interactions requires a multidisciplinary approach. Synchrotron X-ray solution scattering and constrained modelling resulted in the determination of the solution structure of CFH and its self-associative properties, whereas AUC (analytical ultracentrifugation) identified the formation of much larger CFH multimers through the addition of metals such as zinc. The ligands of CFH, such as CRP (C-reactive protein), also undergo self-association. The combination of X-rays and AUC with SPR (surface plasmon resonance) proved to be essential to identify CRP self-association and revealed how CFH interacts with CRP. We show that CRP unexpectedly binds to CFH at two non-contiguous sites and explain its relevance to age-related macular degeneration.
Selection of soluble protein expression constructs: the experimental determination of protein domain boundaries
Authors: Dyson Michael R.
Published: July 2010

Proteins can contain multiple domains each of which is capable of possessing a separate independent function and three-dimensional structure. It is often useful to clone and express individual protein domains to study their biochemical properties and for structure determination. However, the annotated domain boundaries in databases such as Pfam or SMART are not always accurate. The present review summarizes various strategies for the experimental determination of protein domain boundaries.
Proteomic Complex Detection using Sedimentation (ProCoDeS): screening for proteins in stable complexes and their candidate interaction partners
Authors: Segura Marcelo P. , Lilley Kathryn S. , Dupree Paul
Published: July 2010

Over the last few years, our view of cellular organization has changed from one in which enzymes and proteins usually act independently to the situation at present where we commonly accept that many, if not all, enzymes act in close association with others. Co-precipitation using an antibody against a test protein is the standard assay for the identification of members of protein complexes [Musso, Zhang and Emili (2007) Chem. Rev. 107, 3585–3600]. The introduction of TAP (tandem affinity purification) tagging enhanced original approaches in order to analyse protein complexes on a larger scale with reduced false discoveries of interacting partners due to more efficient purification of complexes. However, this technique has some limitations as a high-throughput tool for systems biology: the requirement for genetic manipulation to express the tagged protein excludes studies of non-transformable organisms and intact tissue. In those cases where TAP is applicable, a considerable amount of work is required to generate the baits and to optimize experimental conditions. A technique developed in our laboratories, ProCoDeS (Proteomic Complex Detection using Sedimentation), focuses on the detection of endogenous complexes. Protein samples are separated by centrifugation and then different fractions from the resulting gradient are analysed using quantitative MS. The identification of possible protein partners is based on statistical analysis of the co-fractionation of proteins, without any need for purification of individual complexes. The prospects of ProCoDeS and similar techniques based on quantitative MS for measurement of protein complex composition are reviewed in the present article.