bluuebunny/crossref_metadata_2025_split huggingface dataset:
White biotechnology for cellulose manufacturing—The HoLiR concept
Authors: Kralisch Dana , Hessler Nadine , Klemm Dieter , Erdmann Rainer , Schmidt Wolfgang 
Published: October 2009

AbstractA variety of approaches are available for generation of bacteria‐produced nanocellulose (BNC) in different forms. BNC production under static cultivation conditions usually results in fleeces or foils, characterized by a homogeneous, three‐dimensional network of nanofibers and a uniform surface. However, under static cultivation conditions in batch vessels, the widths and the lengths of the BNC sheets cultured are determined by the dimensions of the culture vessel. In this contribution, a novel, efficient process for a (semi‐)continuous cultivation of planar BNC fleeces and foils with a freely selectable length and an adjustable height is presented. By means of comprehensive investigations, the comparability of the BNC harvested to that gained from static cultivation under batch conditions is demonstrated. A first estimation of the production costs further shows that this type of processing allows for significant cost reductions compared to static cultivation of BNC in Erlenmeyer flasks. Biotechnol. Bioeng. 2010. 105: 740–747. © 2009 Wiley Periodicals, Inc.
Control of Lipase Enantioselectivity by Engineering the Substrate Binding Site and Access Channel
Authors: Lafaquière Vincent , Barbe Sophie , Puech‐Guenot Sophie , Guieysse David , Cortés Juan , Monsan Pierre , Siméon Thierry , André Isabelle , Remaud‐Siméon Magali 
Published: October 2009

AbstractLipase from Burkholderia cepacia (BCL) has proven to be a very useful biocatalyst for the resolution of 2‐substituted racemic acid derivatives, which are important chiral building blocks. Our previous work showed that enantioselectivity of the wild‐type BCL could be improved by chemical engineering of the substrate's molecular structure. From this earlier study, three amino acids (L17, V266 and L287) were proposed as targets for mutagenesis aimed at tailoring enzyme enantioselectivity. In the present work, a small library of 57 BCL single mutants targeted on these three residues was constructed and screened for enantioselectivity towards (R,S)‐2‐chloro ethyl 2‐bromophenylacetate. This led to the fast isolation of three single mutants with a remarkable tenfold enhanced or reversed enantioselectivity. Analysis of substrate docking and access trajectories in the active site was then performed. From this analysis, the construction of 13 double mutants was proposed. Among them, an outstanding improved mutant of BCL was isolated that showed an E value of 178 and a 15‐fold enhanced specific activity compared to the parental enzyme; thus, this study demonstrates the efficiency of the semirational engineering strategy.
CH Functionalizations by Means of Direct Borane–Hydrocarbon Dehydrogenations and Dehydrocarbonations
Authors: Goldfuss Bernd 
Published: October 2009

AbstractThe CH functionalization of methane by means of direct CH borations with BH3 or MeBH2 is compared computationally (using the B3LYP/6‐311++G** method) to CH lithiations with LiH or LiMe as well as to other analogue C–metal (Be, Na, Mg, Al) formations. For the borations only, this internal electrophilic substitution at carbon (SEi) relies more on the electrophilicity of boron than on the basicity of the internal base Y, that is, H or Me. Such direct borations of methane are more favored for dehydrogenations than for dehydrocarbonations. Due to decreased electrophilicity, substituents at boron disfavor such borations. Hence, the BH2 group appears to be most efficient for CH functionalizations by means of direct hydrocarbon borations.
Gewinnung eines partialglyceridhaltigen Biokraftstoffs durch enzymatische Teilethanolyse von Pflanzenöl
Authors: Stäbler A. , Menner M. , Eisner P. 
Published: October 2009

AbstractDie Bedeutung pflanzenölbasierter Kraftstoffe, insbesondere von Biodiesel, steigt ständig an. Allerdings weisen gängige Verfahren zur Biodieselherstellung gravierende Nachteile auf, wie ein aufwendiges Downstream Processing und eine geringe Kraftstoffausbeute. Der vorliegende Artikel beschreibt grundlegende Arbeiten zur Herstellung eines neuartigen, partialglyceridhaltigen Biokraftstoffes mittels sn‐1,3‐regiospezifischen Lipasen. Bei diesem nebenproduktfreien Verfahren wird eine nahezu vollständige Kraftstoffausbeute erreicht. Eine Aufreinigung des Produktes entfällt.
Persistent Troponin Elevation in a Patient with Cardiac Amyloidosis
Authors: Kraemer Bjoern F. , Seizer Peter , Geisler Tobias , Klingel Karin , Kandolf Reinhard , Lindemann Stephan , Gawaz Meinrad 
Published: October 2009

AbstractA 79‐year‐old patient repeatedly presented with chest discomfort and dyspnea on exertion. With echocardiography a prominent left ventricular and septal hypertrophy was detected with reduced left ventricular function. Despite successful revascularization and excellent results after stenting, the patient showed persistently elevated troponin levels. To investigate the abnormal findings of persistent troponin elevation, septal hypertrophy, and heart failure we performed endomyocardial biopsies which showed widespread myocardial amyloidosis. Amyloid subtyping revealed transthyretin amyloidosis. This is the first case showing persistent troponin elevation in a patient with tranthyretin amyloidosis. Very few other cases have been published on the topic of cardiac amyloidosis and troponin elevation so far. Our case serves as an illustrating example in the differential diagnosis of nonischemic causes of persistent troponin elevation. It is important to consider cardiac amyloidosis in patients with troponin elevation and heart failure since the clinical management differs significantly from other causes of heart failure. Copyright © 2009 Wiley Periodicals, Inc.
Traumatic Brachiocephalic Pseudoaneurysm Presenting as Stroke in a Seventeen‐Year‐Old
Authors: Kanwar Manreet , Desai Devang , Joumaa Mouhammed , Guduguntla Vamshidhar 
Published: October 2009

AbstractWe present a 17‐y‐old male who presented to the emergency room with left arm weakness along with slurred speech. On physical examination, he had stable vital signs with left facial weakness suggestive of lower motor neuron seventh nerve palsy. He was also noted to have a small pulsatile mass in the right infraclavicular region. Further questioning revealed that 3 mo earlier he had suffered blunt chest wall trauma during a football game with fracture–dislocation of the right clavicular head, which was managed conservatively. MRI of the brain showed right frontal cortical changes suggestive of infarct versus vasculitis or edema. Chest CT revealed a 2.5‐ to 3‐cm pseudoaneurysm arising from the brachiocephalic artery, with thrombus formation, along with a surrounding 3 × 4.5 cm hematoma. The patient underwent a successful repair of the pseudoaneurysm with no further neurological sequelae. Traumatic pseudoaneurysm with thrombus formation is an extremely rare cause of stroke. It has been reported in association with the carotid artery, but to our knowledge, this is the first reported case with isolated innominate artery pseudoaneurysm. This case highlights the need for a broad differential when evaluating young patients with neurological deficits. Copyright © 2009 Wiley Periodicals, Inc.
Anatomical Factors Triggering Platypnea‐Orthodeoxia in Adults
Authors: Sanikommu Vijaya , Lasorda David , Poornima Indu 
Published: October 2009

AbstractRight to left shunting through a patent foramen ovale (PFO) or atrial septal defect (ASD) can cause platypnea‐orthodeoxia even in a setting of normal pulmonary artery pressures. However, the late onset of symptoms despite the congenital origin of the anatomical defects is not well understood. We report a case series of patients presenting with dyspnea and orthodeoxia who developed right to left shunting as a result of associated anatomical changes that occur with aging such as tortuosity and elongation of the aorta. We propose that these acquired anatomical changes can favor right to left shunting in the setting of congenital abnormalities, therefore explaining the late onset of symptoms. Copyright © 2009 Wiley Periodicals, Inc.
Association of Cystatin C with Ischemia in Patients with Coronary Heart Disease
Authors: Deo Rajet , Shlipak Michael G. , Ix Joachim H. , Ali Sadia , Schiller Nelson B. , Whooley Mary A. 
Published: October 2009

AbstractBackgroundElevated concentrations of cystatin C are associated with greater cardiovascular morbidity and mortality. We sought to determine whether elevated concentrations of cystatin C were associated with inducible ischemia in patients with coronary heart disease (CHD).MethodsWe measured serum cystatin C and performed exercise treadmill testing with stress echocardiography in a cross‐sectional study of 899 outpatients with CHD.ResultsAmong the 241 participants in the highest quartile of cystatin C (>1.30 mg/L), 38% had inducible ischemia, compared with 13% of those in the lowest quartile of cystatin C < 0.92 mg/L; adjusted odds ratio [OR]: 2.1; 95% confidence interval [CI]: 1.2 to 3.8; p = 0.01). However, this association differed in participants with and without a history of coronary artery bypass graft (CABG), as well as in users and nonusers of beta‐blockers and statins (p values for interaction < 0.1). Among participants without a history of CABG, 35% of those in the highest quartile and 9% of those in the lowest quartile of cystatin C had inducible ischemia (adjusted OR: 3.05; 95% CI: 1.3–6.9; p = 0.008). Among participants who were not using beta‐blockers, 44% of those in the highest quartile and 7% in the lowest quartile of cystatin C had inducible ischemia (adjusted OR: 5.3; 95% CI: 1.8–15.5; p = 0.002). Among participants who were not using statins, 39% of participants in the highest quartile and 4% of those in the lowest quartile had inducible ischemia (adjusted OR: 10.3; 95% CI: 2.5–43.3; p = 0.001).ConclusionsElevated levels of cystatin C are independently associated with inducible ischemia among outpatients with stable coronary disease. Copyright © 2009 Wiley Periodicals, Inc.
Nonapical Tako‐tsubo Cardiomyopathy Associated with Coronary Slow Flow: A Case Report and Review of the Literature
Authors: Krishnan Unni , Zacharzewski Amanda , Schmitt Matthias 
Published: October 2009

AbstractThe exact pathophysiology of tako‐tsubo cardiomyopathy (TTC) is unclear. A nonapical form of TTC precipitated by emotional stress is presented. Findings on 12 lead ECG and coronary angiogram are discussed. The role of specialized investigations such as cardiac MRI and tissue Doppler imaging are reviewed. We then examine the probable molecular explanations for this condition and suggest a probable molecular mechanism based on animal studies. Future therapeutic options are also briefly discussed. Copyright © 2009 Wiley Periodicals, Inc.
ST Deviation Pattern and Infarct Related Artery in Acute Myocardial Infarction
Authors: Rott David , Nowatzky Johannes , Teddy Weiss A. , Chajek‐Shaul Tova , Leibowitz David 
Published: October 2009

AbstractBackgroundMyocardial infarction (MI) may be classified as ST‐elevation MI (STEMI) or non‐ST‐elevation MI (NSTEMI). There is little data regarding the relationship between the infarct related artery (IRA), clinical characteristics of the patients, and the ST deviation pattern (ie, STEMI or NSTEMI).HypothesisThere is a predilection of any coronary artery to a particular ST deviation pattern of acute MI.MethodsWe reviewed our institutional database and selected patients who presented with an acute MI and underwent coronary angiography within 7 days of admission. The analysis included 830 patients of whom 563 had STEMI and 267 had NSTEMI. The culprit lesion was defined by reviewing each patient's angiographic report, electrocardiogram, and echocardiogram. TIMI flow rate was determined.ResultsThe IRA in STEMI was most frequently the left anterior descending coronary artery (LAD) followed by the right coronary artery (RCA) and then the left circumflex coronary artery (LCX), a statistically significant difference. In patients with NSTEMI there were no significant differences in IRA. Patients with STEMI and LCX as the IRA were significantly younger and had a higher percentage of TIMI grade 3 flow then patients with STEMI and LAD or RCA as IRAs. These differences were not noted in patients with NSTEMI regardless of IRA.ConclusionsIn STEMI there were significant differences in age and TIMI flow depending on the IRA. These findings were not demonstrated in patients with NSTEMI. Copyright © 2009 Wiley Periodicals, Inc.
Appearance of Electrocardiographic Initial U‐Wave Inversion Dependent on Pressure‐Induced Early Diastolic Impairment in Patients with Hypertension
Authors: Miwa Kunihisa 
Published: October 2009

AbstractBackgroundECG U‐wave inversion can be classified as initial and terminal U inversion according to the phasic relationship to positive U‐wave deflection. Initial U inversion is occasionally observed in hypertensive patients while terminal U inversion frequently appears during severe myocardial ischemia.HypothesisThe genesis of initial U inversion may be related to pressure‐induced diastolic dysfunction.MethodsIn order to clarify the genesis of initial U‐wave inversion we studied 11 consecutive hypertensive patients with both initial U inversion and impaired left ventricular early relaxation who were evaluated using Doppler echocardiography.ResultsThe U inversion disappeared during acute pressure lowering by sublingual administration of nitroglycerin. The U inversion also disappeared and relaxation improved significantly after chronic blood pressure lowering. Initial U inversion reappeared during a cold pressor test.ConclusionThe appearance of initial U inversion was dependent on the pressure‐induced impaired left ventricular early relaxation in hypertensive patients. Copyright © 2009 Wiley Periodicals, Inc.
A Combined Experimental and Theoretical Study on the Magnetic Properties of a Family of Bis(μ‐phenoxido)dicopper(II) Complexes Bearing ω‐[Bis(2‐hydroxy‐3,5‐dimethylbenzyl)amino]alkan‐1‐ol Ligands
Authors: Wichmann Oula , Sopo Harri , Colacio Enrique , Mota Antonio J. , Sillanpää Reijo 
Published: October 2009

AbstractFive new neutral bis(μ‐phenoxido)dicopper(II) complexes, [Cu2(μ‐HL1)2]·3EtOH·H2O (1), [Cu2(μ‐HL2)2]·1.65H2O (2), [Cu2(μ‐HL3)2(μ‐H2O)] (3), [Cu2(μ‐HL4)2] (4) and [Cu2(μ‐HL5)2(μ‐H2O)] (5), were prepared from a family of ω‐[bis(2‐hydroxy‐3,5‐dimethylbenzyl)amino]alkan‐1‐ol ligands (H3L1–H3L5 derived from 2‐aminoethanol, 3‐aminopropanol, 4‐aminobutanol, 5‐aminopentanol and 6‐aminohexanol, respectively) bearing a [O,N,O,O′] donor set. In complexes 3 and 5, there is also a bridging water molecule between the metallic centres. The copper(II) coordination planes of all these complexes form a roof‐like structure (the bridging O atoms are located at the top of the roof). The structural differences found for the different complexes and their relation with the magnetic properties is discussed below. Magnetic studies of these dinuclear complexes showed that J values vary from –470.8 to –91.2 as the Cu–O–Cu angles (θ) vary from 100.66(9) to 92.76(7)°. DFT theoretical calculations produced the corresponding magnetic exchange coupling constants, finding that these values are quite near to the experimental ones. A linear relationship between the calculated J values and θ was observed, clearly supporting that the major factor controlling the magnetic exchange coupling in this series of complexes is, by far, the Cu–O–Cu bridging angle. The crossover point below which the magnetic behaviour changes from antiferromagnetic to ferromagnetic coupling is predicted at ≈ 89°. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Theoretical Analysis of the Possible Intermediates in the Formation of [W6O19]2–
Authors: Vilà‐Nadal Laia , Rodríguez‐Fortea Antonio , Poblet Josep M. 
Published: October 2009

AbstractThe structural features and the dynamic behaviour of different possible intermediates in the formation of the Lindqvist anion, [W6O19]2–, according to the stoichiometries observed in electrospray fragmentation experiments, were analyzed by DFT calculations. Two different and complementary techniques were used to take into account the effect of the solvent in the computations: (i) continuum solvation models and (ii) Car–Parrinello simulations with explicit solvent molecules. The interaction of the WVI ions with the nucleophilic water molecules expands their coordination sphere, reaching in many cases octahedral coordination. Furthermore, a common structural motif (“building block”) is observed in the most stable structures of the intermediates with higher nuclearities. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Aluminium Triflate Catalysed Cyclisation of Unsaturated Alcohols: Novel Synthesis of Rose Oxide and Analogues
Authors: Coulombel Lydie , Weïwer Michel , Duñach Elisabet 
Published: October 2009

AbstractAluminium trifluoromethanesulfonate was used as an efficient catalyst for the cycloisomerisation of several unsaturated alcohols into cyclic ethers such as rose oxide and some of its ether analogues. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Supramolecular Photochirogenesis with Carbenes Entrapped in Cyclodextrins
Authors: Mieusset Jean‐Luc , Wagner Gerald , Su Kuan‐Jen , Steurer Marianne , Pacar Mirjana , Abraham Michael , Brinker Udo H. 
Published: October 2009

AbstractTwo achiral diazirines 1a and 1b have been encapsulated in the inherently chiral cavity of α‐cyclodextrin (6‐Cy), β‐cyclodextrin (7‐Cy) and permethylated β‐cyclodextrin (TRIMEB) and photolyzed. Because of supramolecular photochirogenesis the generated carbenes afford intramolecular C–H insertion products not as a racemate but one enantiomer is slightly favored. With 1a@(6‐Cy)2 the ee of product 7a is doubled. To the best of our knowledge for the first time for carbene reactions, products are imprinted, though modestly, with handedness derived from Cys. The reaction of 1b is highly dependent on the molecular reactor used for inclusion. Whereas 7‐Cy is very efficient for favoring dimerization through azine formation, the use of TRIMEB permits exclusive formation of intramolecular insertion product 7b. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
The Comparison of Electrochemical Assay and Agarose Gel Electrophoresis for the Determination of DNA Damage Induced by Kainic Acid
Authors: Karadeniz Hakan , Armagan Guliz , Erdem Arzum , Turunc Ezgi , Caliskan Ayfer , Kanit Lutfiye , Yalcin Ayfer 
Published: October 2009

AbstractA possible DNA damage after interaction of kainic acid (KA) with calf thymus double stranded DNA and genomic DNA was herein determined in in vitro and in vivo conditions using; electrochemical assay and agarose gel electrophoresis. The changes in guanine signal were detected as an indicator of DNA damage in genomic DNA samples isolated from 1 or 10 mg/kg KA‐treated animals. The decreased levels of guanine signal were found as 29% and 33% by 1 and 10 mg/kg KA treatment when compared to controls, respectively. The results of gel electrophoresis confirmed DNA damage obtained in identical samples by electrochemical method.
Electrochemiluminescence of CdSe Quantum Dots Composited with Nitrogen‐Doped Carbon Nanotubes
Authors: Guo Liang , Liu Xuan , Hu Zheng , Deng Shengyuan , Ju Huangxian 
Published: October 2009

AbstractA nanocomposite of CdSe quantum dots with nitrogen‐doped carbon nanotubes was prepared for enhancing the electrochemiluminescent (ECL) emission of quantum dots. With hydrogen peroxide as co‐reactant, the nanocomposite modified electrode showed a cathodic ECL emission with a starting potential of −0.97 V (vs. Ag/AgCl) in phosphate buffer solution, which was five‐times stronger than that from pure CdSe quantum dots and three‐times stronger than that from CdSe quantum dots composited with carbon nanotubes. The latter showed a starting potential of −1.19 V. This result led to a sensitive ECL sensing of hydrogen peroxide with good stability, acceptable reproducibility and a detection limit down to 2.1×10−7 mol L−1. Nitrogen‐doped carbon nanotubes could be used as a good material for the construction of sensitive ECL biosensors for chemical and biochemical analysis.
Epinephrine Oxidation in the Presence of Interfering Molecules on Gold and Gold Electrodes modified with Gold Nanoparticles and Thiodipropionic Acid in Aqueous Solution. A Comparative Study
Authors: Łuczak Teresa 
Published: October 2009

AbstractThiodipropionoc acid (TDPA), cysteamine (CA) and gold nanoparticles (Au‐NPs) modified gold pure electrodes have been applied in voltammetric sensors for simultaneous detection of epinephrine (EP), ascorbic (AA) and uric (UA) acids. Modified electrodes with self assembled layers (SAMs) show high selectivity, sensitivity, reproducibility and stability. A linear relationship between the epinephrine concentration and the current response is obtained in the range of 0.1 μM to 0.65 μM with the detection limit ≤0.065 μM for the electrodes modified at 2D surface and in the range of 0.1 μM to 0.75 μM with the detection limit ≤0.082 μM for the electrodes modified at the 3D surface.
Effect of urea on analyte complexation by 2,6‐dimethyl‐β‐CD in peptide enantioseparations by CE
Authors: Hammitzsch‐Wiedemann Manuela , Scriba Gerhard K. E. 
Published: October 2009

AbstractThe aim of the present study was the investigation of the effect of urea on analyte complexation in CD‐mediated separations of peptide enantiomers by CE in the pH range of about 2–5. pH‐independent complexation and mobility parameters in the absence and presence of 2 M urea were obtained by three‐dimensional, non‐linear curve fitting of the effective analyte mobility as a function of pH and heptakis‐(2,6‐di‐O‐methyl)‐β‐CD concentration. Urea led to decreased binding strength of the CD towards the protonated and neutral analyte enantiomers as well as to decreased mobilities of the free analytes. In contrast, mobilities of the fully protonated enantiomer–CD complexes as well as the pKa values of the free and complexed analytes increased. The effect of urea on separation efficiency varied with pH and CD concentration. In the case of Ala‐Tyr and Ala‐Phe, separations improved in the presence of urea at pH 2.2. In contrast, separations were impaired by urea at pH 3.8 and low concentrations of the CD. Decreased separation efficiency was noted for Asp‐PheOMe and Glu‐PheNH2 at low CD concentrations when urea was added but separations improved at higher CD concentrations over the entire pH range studied. The effect of urea on analyte complexation appeared to be primarily non‐stereoselective. Furthermore, the pH‐dependent reversal of the enantiomer migration order observed for Ala‐Tyr and Ala‐Phe can be rationalized by the complexation and mobility parameters.
Design of UEP‐Raptor codes over BEC
Authors: Yuan Lei. , An Jianping 
Published: October 2009

AbstractIn this paper, we propose a new scheme to construct Raptor codes that can provide unequal error protection (UEP) and unequal recovery time (URT) properties. We use joint optimisation of UEP‐LDPC codes and UEP‐LT codes to improve the performance of more important bits (MIB), and derive unequal density evolution (UDE) formulas over binary erasure channels (BEC). Using the UDE formulas, we optimise the UEP‐Raptor codes. For the finite length case, we compare our UEP‐Raptor codes with the previous UEP‐Raptor code. Simulation results show that, compared with the previous UEP‐Raptor code, the proposed UEP‐Raptor codes can get better performances of both MIB and less important bits (LIB). Copyright © 2009 John Wiley & Sons, Ltd.