bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metabolic adaptation of MDCK cells to different growth conditions: Effects on catalytic activities of central metabolic enzymes
Authors: Janke R. , Genzel Y. , Händel N. , Wahl A. , Reichl U. 
Published: May 2011

AbstractLactate and ammonia are the most important waste products of central carbon metabolism in mammalian cell cultures. In particular during batch and fed‐batch cultivations these toxic by‐products are excreted into the medium in large amounts, and not only affect cell viability and productivity but often also prevent growth to high cell densities. The most promising approach to overcome such a metabolic imbalance is the replacement of one or several components in the culture medium. It has been previously shown that pyruvate can be substituted for glutamine in cultures of adherent Madin–Darby canine kidney (MDCK) cells. As a consequence, the cells not only released no ammonia but glucose consumption and lactate production were also reduced significantly. In this work, the impact of media changes on glucose and glutamine metabolism was further elucidated by using a high‐throughput platform for enzyme activity measurements of mammalian cells. Adherent MDCK cells were grown to stationary and exponential phase in six‐well plates in serum‐containing GMEM supplemented with glutamine or pyruvate. A total number of 28 key metabolic enzyme activities of cell extracts were analyzed. The overall activity of the pentose phosphate pathway was up‐regulated during exponential cell growth in pyruvate‐containing medium suggesting that more glucose‐6‐phosphate was channeled into the oxidative branch. Furthermore, the anaplerotic enzymes pyruvate carboxylase and pyruvate dehydrogenase showed higher cell specific activities with pyruvate. An increase in cell specific activity was also found for NAD+‐dependent isocitrate dehydrogenase, glutamate dehydrogenase, and glutamine synthetase in MDCK cells grown with pyruvate. It can be assumed that the increase in enzyme activities was required to compensate for the energy demand and to replenish the glutamine pool. On the other hand, the activities of glutaminolytic enzymes (e.g., alanine and aspartate transaminase) were decreased in cells grown with pyruvate, which seems to be related to a decreased glutamine metabolism. Biotechnol. Bioeng. 2011;108: 2691–2704. © 2011 Wiley Periodicals, Inc.
Controlling glycation of recombinant antibody in fed‐batch cell cultures
Authors: Yuk Inn H. , Zhang Boyan , Yang Yi , Dutina George , Leach Kimberly D. , Vijayasankaran Natarajan , Shen Amy Y. , Andersen Dana C. , Snedecor Bradley R. , Joly John C. 
Published: May 2011

AbstractProtein glycation is a non‐enzymatic glycosylation that can occur to proteins in the human body, and it is implicated in the pathogenesis of multiple chronic diseases. Glycation can also occur to recombinant antibodies during cell culture, which generates structural heterogeneity in the product. In a previous study, we discovered unusually high levels of glycation (>50%) in a recombinant monoclonal antibody (rhuMAb) produced by CHO cells. Prior to that discovery, we had not encountered such high levels of glycation in other in‐house therapeutic antibodies. Our goal here is to develop cell culture strategies to decrease rhuMAb glycation in a reliable, reproducible, and scalable manner. Because glycation is a post‐translational chemical reaction between a reducing sugar and a protein amine group, we hypothesized that lowering the concentration of glucose—the only source of reducing sugar in our fed‐batch cultures—would lower the extent of rhuMAb glycation. When we decreased the supply of glucose to bioreactors from bolus nutrient and glucose feeds, rhuMAb glycation decreased to below 20% at both 2‐L and 400‐L scales. When we maintained glucose concentrations at lower levels in bioreactors with continuous feeds, we could further decrease rhuMAb glycation levels to below 10%. These results show that we can control glycation of secreted proteins by controlling the glucose concentration in the cell culture. In addition, our data suggest that rhuMAb glycation occurring during the cell culture process may be approximated as a second‐order chemical reaction that is first order with respect to both glucose and non‐glycated rhuMAb. The basic principles of this glycation model should apply to other recombinant proteins secreted during cell culture. Biotechnol. Bioeng. 2011;108: 2600–2610. © 2011 Wiley Periodicals, Inc.
Optimizing antiplatelet therapy in acute coronary syndrome and percutaneous coronary intervention
Authors: Faxon David P. 
Published: May 2011

AbstractDual antiplatelet therapy with aspirin and clopidogrel is the standard of care for patients with acute coronary syndrome (ACS) and those undergoing percutaneous coronary intervention (PCI). It is well established that inhibition of platelet aggregation reduces the risk of recurrent thrombotic events and stent thrombosis. However, some patients show a reduced antiplatelet response to standard clopidogrel loading (300 mg) and maintenance (75 mg day−1) doses, which has been associated with poorer patient outcomes. Pharmacodynamic and pharmacokinetic studies show that higher‐than‐standard clopidogrel dosing strategies facilitate more rapid platelet inhibition of a greater intensity as a result of greater plasma concentrations of the clopidogrel active metabolite. Recently completed studies suggest that in patients with ACS undergoing PCI, higher‐than‐standard clopidogrel dosing regimens provide greater inhibition of platelet function and improved clinical outcomes with a small but significant increase in major bleeding. Newer, more potent antiplatelet agents such as prasugrel and ticagrelor are other alternative strategies that result in more rapid, greater inhibition of platelet function and better outcomes than standard‐dose clopidogrel. Whether platelet reactivity‐guided therapy or genotyping for cytochrome P450 polymorphisms is useful in managing patients needs to be further defined. Most importantly, early and effective antiplatelet therapy results in the best short‐ and long‐term outcomes for patients with ACS or those undergoing PCI. © 2011 Wiley‐Liss, Inc.
High Fidelity Self‐Recognition of Isomeric Oligopyridines in Binary 2D Self‐Assembly and Its Application for Separation
Authors: Caterbow Daniel , Roos Matthias , Hoster Harry E. , Behm R. Jürgen , Landfester Katharina , Ziener Ulrich 
Published: May 2011

AbstractSelf‐assembly in two binary mixtures based on three isomeric oligopyridines at the liquid/HOPG (highly oriented pyrolytic graphite) interface is presented. Despite their structural similarity the molecules display exclusive phase separation, which is attributed to the highly specific intermolecular hydrogen bonding interactions. Variation of the mole fractions in solution reveal strongly preferred adsorption of the major compound, which underlines the importance of self‐recognition for self‐assembly. Those findings at the molecular level can be applied to separation issues on a macroscopic scale, leading to a completely new concept of separation, which could have a strong impact on various chromatographic processes.
Development of a Flexible Strategy towards FR900482 and the Mitomycins
Authors: Trost Barry M. , O'Boyle Brendan M. , Torres Wildeliz , Ameriks Michael K. 
Published: May 2011

AbstractFR900482 and the mitomycins are two intriguing classes of alkaloid natural products that have analogous biological mechanisms and obvious structural similarity. Both classes possess potent anticancer activity, a feature that has led to their investigation and implementation for the clinical treatment of human cancer. Given the structural similarity between these natural products, we envisioned a common synthetic strategy by which both classes could be targeted through assembling the mitomycin skeleton prior to further oxidative functionalization. Realization of this strategy with respect to FR900482 was accomplished through the synthesis of 7‐epi‐FR900482, which displayed equal potency relative to the natural product against two human cancer cell lines. With the challenging goal of a synthesis of either mitomycin or FR900482 in mind, several methodologies were explored. While not all of these methods ultimately proved useful for our synthetic goal, a number of them led to intriguing findings that provide a more complete understanding of several methodologies. In particular, amination via π‐allyl palladium complexes for the synthesis of tetrahydroquinolines, eight‐membered heterocycle formation via carbonylative lactamization, and amination through late‐stage CH insertion via rhodium catalysis all featured prominently in our synthetic studies.
Self‐Assembly Into Spheres of a Hybrid Diphenylalanine–Porphyrin: Increased Fluorescence Lifetime and Conserved Electronic Properties
Authors: Charalambidis Georgios , Kasotakis Emmanouil , Lazarides Theodore , Mitraki Anna , Coutsolelos Athanassios G. 
Published: May 2011

AbstractA series of protected phenylalanine and diphenylalanine derivatives have been coupled through a peptide bond to a monoaminoporphyrin to form new materials. A comparative study in solution and in the solid state has been performed and confirmed new and interesting properties for the self‐assembled hybrid materials while conserving the electronic properties of the chromophore. Thus, they are powerful candidates for use in dye‐sensitized solar cells.
Fibrous architectures and organogels of tris(phenylethynylphenyl)adamantane molecules with amino acid moieties: Their solvato‐controlled helicity induction
Authors: Tominaga Masahide , Azumaya Isao 
Published: May 2011

AbstractNon‐disk‐shaped molecules self‐assembled to form columnar‐type helical aggregates with gel ability through π‐stacking interactions among the central tris(phenylethynylphenyl)adamantane moieties, hydrogen‐bonding interactions among the alanine parts with amide groups, and van der Waals interactions among the alkyl groups in nonpolar n‐alkanes. The structural analyses of fibrous architectures with helicity were examined by FTIR, UV‐Vis, and circular dichroism (CD) spectroscopy and FE‐SEM measurements. In contrast, the formation of fibrous structures was observed from adamantane‐based tripodal molecules due to solvophobic interactions in polar EtOH, which showed no detectable Cotton effect in the CD measurement, indicating the induction of solvato‐controlled helicity in the self‐assembly process. Chirality 2011. © 2011 Wiley Periodicals, Inc.
Highly Dispersed MoO3/Al2O3 Shell‐Core Composites Synthesized by CVD of Mo(CO)6 under Atmospheric Pressure
Authors: Shi Guojun , Franzke Thomas , Xia Wei , Sanchez Miguel D. , Muhler Martin 
Published: May 2011

AbstractMoO3/γ‐Al2O3 composites are synthesized by CVD under atmospheric pressure using Mo(CO)6 as the precursor and porous γ‐Al2O3 particles in a horizontal, rotating, hot‐wall reactor, which is also used for calcination in air. The composites are characterized by N2 physisorption, atomic absorption spectroscopy, X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD), transmission electron microscopy (TEM), and laser Raman spectroscopy (LRS). The synthesized samples exhibit excellent porosity, even at high Mo loadings. A much higher Mo yield is achieved when applying sublimation‐adsorption in static air instead of using flowing N2. A high degree of Mo dispersion on alumina is confirmed by XRD, LRS, and TEM; with a Mo surface density as high as 5.2 atoms nm−2, the sample is X‐ray amorphous, there are no polymeric molybdate species detectable by LRS, and the island size of the molybdate species is about 1 nm according to TEM. The XPS analysis shows that exclusively MoVI species are present on all synthesized samples. Thus, the applied rotating, hot‐wall reactor achieves efficient mixing and homogeneous deposition.
Periductal mastitis in a male breast masquerading as lobular carcinoma on fine needle aspiration cytology
Authors: Gupta Nalini , Agrawal Pallavi , Saikia Uma Nahar , Das Ashim , Srinivasan Radhika , Rajwanshi Arvind , Singh Gurpreet 
Published: May 2011

AbstractFine needle aspiration cytology (FNAC) is quite successful in identifying specific benign and malignant breast lesions, but its role in the categorization of proliferative breast lesions has not been well defined. Mastitis/ breast abscess can lead to intense inflammatory response; however, its association with epithelial hyperplasia is rarely reported. At times, it may be difficult to differentiate dense lymphoplasmacytic infiltrate from non‐Hodgkin's lymphoma. We present a case of periductal mastitis associated with epithelial hyperplasia, presenting as a subaerolar swelling in a male breast, which was misinterpreted as lobular carcinoma on FNAC. Diagn. Cytopathol. 2011; © 2011 Wiley‐Liss, Inc.
Histomorphological study of palatal shelf elevation during murine secondary palate formation
Authors: Yu Kai , Ornitz David M. 
Published: May 2011

AbstractDuring mammalian secondary palate development, the palatal shelves undergo dramatic morphological changes to elevate from a vertical to a horizontal plane in the oral‐nasal cavity. We found that E14.5 mouse embryos displayed marked variations in shelf morphology that represent various intermediate states of the elevation process. With these variations, we reconstructed the sequence of shelf morphological changes that take place during the elevation process and discovered distinct patterns in different regions along the anterior‐posterior (AP) axis. Moreover, our study revealed that during the elevation process, shelf morphological changes are accompanied by tongue morphological changes, which also show distinct characteristics along the AP axis. We further discuss how to divide the palate along the AP axis based on morphological criteria. Our study provides a framework that recognizes variation in timing of palatal morphogenesis along the AP axis that will aid in the investigation of the mechanisms regulating palatal shelf elevation. Developmental Dynamics 240:1737–1744, 2011. © 2011 Wiley‐Liss, Inc.
Synthesis, Structure, and Thermoelectric Properties of Barium Copper Polychalcogenides with Chalcogen‐Centered Cu Clusters and Te22– Dumbbells
Authors: Mayasree Oottil , Sankar Cheriyedath Raj , Cui Yanjie , Assoud Abdeljalil , Kleinke Holger 
Published: May 2011

AbstractBaCu6–xSTe6 and BaCu6–xSe1–yTe6+y were synthesized from the elements at 663 K. These chalcogenides adopt a new structure type, cubic space group Pm$\bar {3}$, with a = 6.9680(2) Å in the case of BaCu5.93SeTe6. Therein, the Cu atoms form cubic clusters, centered by Se atoms, where statistically 2.07 corners are unoccupied. All Te atoms are part of Te22– dumbbells, leading to a charge‐balanced formula when x = 0: Ba2+(Cu+)6Se2–(Te22–)3. While Te atoms can be incorporated on the Se site, no evidence was found for the ability of Se atoms to replace Te in the Te22– pairs. Band structure calculations on different BaCu6SeTe6 models revealed a very small band gap at the Fermi level; all these chalcogenides with x > 0 should thus be p‐doped semiconductors, which we experimentally confirmed for BaCu5.7Se0.6Te6.4.
Versatile Zirconium Reductants and Carbon–Carbon Coupling Agents Selectively Accessible from the 2:1 Molar Aggregate of n‐Butyllithium and Zirconium(IV) Salts
Authors: Eisch John J. , Gitua John N. , Yu Kun 
Published: May 2011

AbstractIn previous studies of transition metal alkyls the 2:1 molar aggregate of n‐butyllithium and zirconium(IV) salts has been found to react both with benzylic hydrocarbons and aromatic carbonyl derivatives in diverse and useful ways. In the present study the reactions of the aggregates, 2nBuLi·ZrE4 (E = Cl, OEt), with benzaldehyde have involved carbometallation, hydrometallation and reductive dimerization (paths 1–3) in THF and were selectively achievable by temperature control alone. First, at –78 °C benzaldehyde underwent carbolithiation to give upon hydrolysis 1‐phenyl‐1‐pentanol. However, short‐term reaction times and prompt D2O quenching revealed that with Zr(OEt)4 both benzaldehyde and 1‐phenyl‐1‐pentanol were deuteriated, consistent with the presence of a phenyl(lithioxy)carbene intermediate. The observed dimerization of benzaldehyde to benzyl benzoate by lithium 2,2,6,6‐tetramethylpiperidide is also consistent with such a phenyl(lithioxy)carbene intermediate. Second, at 25 °C the 2nBuLi·ZrE4 aggregate reduced benzaldehyde exclusively to benzyl alcohol, which observation is consistent with the formation of the hydrozirconating agent, H2ZrE2. Third, heating the aggregate at reflux and subsequent reaction with benzaldehyde produced solely the reduced dimer, 1,2‐diphenyl‐1,2‐ethanediol with high stereoselectivity: E = Cl, rac/meso of 93:7 and E = OEt, rac/meso of 100:0. The proposed mechanism involves the formation of ZrE2, the epizirconation of benzaldehyde and the insertion of the second benzaldehyde into the zirconaoxacyclopropane under steric control. Finally, the high selectivity in hydrozirconation and reductive dimerization shown by 2nBuLi·ZrE4 appears at this time to be superior to that attainable with analogous titanium or hafnium aggregates.
Neural basis of the association between depressive symptoms and memory deficits in nondemented subjects: resting‐state fMRI study
Authors: Xie Chunming , Goveas Joseph , Wu Zhilin , Li Wenjun , Chen Guangyu , Franczak Malgorzata , Antuono Piero G. , Jones Jennifer L. , Zhang Zhijun , Li Shi‐Jiang 
Published: May 2011

AbstractDepressive symptoms often coexist with memory deficits in older adults and also are associated with incident cognitive decline in the elderly. However, little is known about the neural correlates of the association between depressive symptoms and memory deficits in nondemented elderly. Fifteen amnestic mild cognitive impairment (aMCI) and 20 cognitively normal (CN) subjects completed resting‐state functional magnetic resonance imaging (R‐fMRI) scans. Multiple linear regression analysis was performed to test the main effects of the Geriatric Depression Scale (GDS) and Rey Auditory Verbal Learning Test delayed recall (RAVLT‐DR) scores, and their interaction on the intrinsic amygdala functional connectivity (AFC) network activity. Severer depressive symptoms and memory deficits were found in the aMCI group than in the CN group. Partial correlation analysis identified that the RAVLT‐DR scores were significantly correlated with the AFC network in the bilateral dorsolateral prefrontal cortex (DLPFC), dorsomedial and anterior prefrontal cortex, posterior cingulate cortex (PCC), middle occipital gyrus, right inferior parietal cortex, and left middle temporal gyrus (MTG). The GDS scores were positively correlated with the AFC network in the bilateral PCC and MTG, and left DLPFC. The interactive effects of the GDS and RAVLT‐DR scores on the AFC network were seen in the bilateral PCC, MTG, and left DLPFC. These findings not only supported that there were interactive neural links between depressive symptoms and memory functions in nondemented elderly at the system level, but also demonstrated that R‐fMRI has advantages in investigating the interactive nature of different neural networks involved in complex functions, such as emotion and cognition. Hum Brain Mapp , 2011. © 2011 Wiley‐Liss, Inc.
fMRI investigation of speed–accuracy strategy switching
Authors: Vallesi Antonino , McIntosh Anthony R. , Crescentini Cristiano , Stuss Donald T. 
Published: May 2011

AbstractSwitching between rapid and accurate responses is an important aspect of decision‐making. However, the brain mechanisms important to smoothly change the speed–accuracy strategy remain mostly unclear. This issue was addressed here by using functional magnetic resonance imaging (fMRI). On each trial, right‐handed healthy participants had to stress speed or accuracy in performing a color discrimination task on a target stimulus according to the instructions given by an initial cue. Participants were capable of trading speed for accuracy and vice versa. Analyses of cue‐related fMRI activations revealed a significant recruitment of left middle frontal gyrus and right cerebellum when switching from speed to accuracy. The left superior parietal lobule was activated in the same switching condition but only after the target onset. The anterior cingulate cortex was more recruited, also after target presentation, when speed had to be maintained from one trial to the next. These results are interpreted within a theoretical framework that attributes a role in criterion‐setting to the left lateral prefrontal cortex, perceptual evidence accumulation to the superior parietal lobule, and action energization to the anterior cingulate cortex, extending previous findings to the domain of speed–accuracy tradeoff regulations. Hum Brain Mapp, 2011. © 2011 Wiley‐Liss, Inc.
Direct numerical simulation of multiphase flows involving dispersed components with deformable interfaces
Authors: Kajishima Takeo , Takeuchi Shintaro 
Published: May 2011

AbstractRecent developments in direct numerical simulation of dispersed multiphase flows are reviewed. A current trend is to use a fixed Cartesian grid, as it is suitable for dealing with multiple solids, bubbles, and/or droplets (dispersed components). The features of several typical methods for gas–liquid interfaces and fluid–solid boundaries are discussed. For gas–liquid interfaces, we categorize the existing techniques into fitting, tracking, capturing, and indicator‐transportation methods in order to clarify the characteristics of the methods. For solid objects moving in a fluid, on the other hand, methods on a fixed Cartesian grid are highlighted. Our primary interest is in the conservation properties of the algorithms. From this point of view, we show a combination of our conservative momentum exchange (CMX) algorithm for immersed solid objects and volume‐of‐fluid (VOF) method for gas–liquid interface. This combination enables simulation of interaction problems between particles and bubbles of comparable sizes (three‐phase flows). As for interaction problems of a deformable solid object with a fluid, we demonstrate the successful coupling of CMX and a finite element method. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.20345