bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerische Simulation von Rammarbeiten im Erdwiderstandsbereich von Baugrubenwänden
Authors: Grabe Jürgen , Henke Sascha , Schümann Björn
Published: August 2007

Baubegleitende Messungen an Baugruben zeigen, dass während der Herstellung, z. B. bei der Rammung von Auftriebspfählen für die Baugrubensohle, erhebliche Verformungen des Baugrubenverbaus eintreten. Diese herstellungsbedingten Zusatzbeanspruchungen lassen sich derzeit kaum zutreffend erfassen und führen in der Ausführung oft zu Erstaunen. Ziel des Beitrags ist es, ein erstes Simulationsmodell der herstellungsbedingten Beanspruchung des Baugrunds und der Baugrube im Nahfeld von Rammarbeiten vorzustellen. Am Beispiel der am Potsdamer Platz gemessenen Zusatzverformung infolge der Rüttelinjektionspfahl‐Herstellung wird die Nützlichkeit der numerischen Untersuchungen erläutert. Allerdings sind zukünftig noch erhebliche Anstrengungen erforderlich, um daraus Empfehlungen für die Herstellung von Baugruben abzuleiten.
Bewertung bestehender Natursteinbogenbrücken
Authors: Purtak Frank , Geißler Karsten , Lieberwirth Peter
Published: August 2007

Bogenbrücken aus Natursteinmauerwerk zählen zu den ältesten noch in voller Funktion befindlichen Tragwerken innerhalb von Straßen‐ und Schienenwegen. Mit einem Bauwerksalter von teilweise weit über 100 Jahren stellen diese in großer Anzahl von mehreren tausend Bauwerken gleichzeitig eine historisch sehr wertvolle Bausubstanz dar.

Die ältesten bestehenden Brücken wurden auf Erfahrungswerten basierend entworfen, später standen grafische Verfahren für statische Nachweise zur Verfügung, man entwickelte Näherungsformeln auf Basis der Bogenstützlinie zum Entwurf wesentlicher Geometrieparameter wie Stützweite, Bogenform sowie Bogendicke an Scheitel und Kämpfer. Im Zuge der Nachrechnung dieser Bauwerke werden Bewertungen hinsichtlich Tragfähigkeit und Gebrauchstauglichkeit auf der Basis heute gültiger Lastansätze und Berechnungsvorschriften gefordert.

Im Beitrag werden neben einem kurzen Überblick zum Bogenbrückenbestand die Möglichkeiten der Tragwerksmodellierung erörtert. Ein Schwerpunkt bildet die Berechnung der Mauerwerkstragfähigkeit, die insbesondere unter Beachtung sicherheitstheoretischer Überlegungen erläutert wird. Die auf den Brückenbau bezogenen Verfahren sind prinzipiell auf Tragwerke des Hochbaus übertragbar.
New cases of thalidomide embryopathy in Brazil
Authors: Schuler‐Faccini Lavinia , Soares Rosa Castalia Franca , de Sousa Artur Custodio Moreira , Maximino Claudia , Luna Expedito , Schwartz Ida Vanessa Doderlein , Waldman Carolina , Castilla Eduardo Enrique
Published: August 2007

Thalidomide is the best known human teratogen. Although withdrawn from the market in 1961, thalidomide was remarketed after 1965 in several countries, for the treatment of erythema nodosum leprosum. Thalidomide has a potent immunomodulatory property and has now a number of approved and off‐label uses in dermatologic, oncologic, infectious and gastrointestinal conditions. In the U.S., FDA approved the use of thalidomide in 1998, but no cases of thalidomide embriophaty were registered after that. Since 1996 no new cases were reported in Latin America. However, the Teratogen Information Service (TIS) Porto Alegre, recorded three new cases of thalidomide embriophaty born in Brazil since 2005. Considering that these three cases were not registered through a systematic surveillance system, but that came to our attention through a series of coincidental random events, it can be assumed that the actual occurrence of affected babies by thalidomide continues being as frequent as denounced ten years ago. Birth Defects Research (Part A), 2007. © 2007 Wiley‐Liss, Inc.
Role of nitric oxide in chick embryonic organogenesis and dysmorphogenesis
Authors: Alexander Peter G. , Chau Lillian , Tuan Rocky S.
Published: August 2007

BACKGROUND: Nitric oxide (NO), produced by the nitric oxide synthase family of enzymes, mediates multiple signaling functions, and when unchecked, NO causes pathological damage. Exposure of embryos to a variety of teratogens, including carbon monoxide (CO), has been shown to increase reactive intermediates, such as NO, and recent work showed that either the excess or absence of NO caused morphological defects. While endogenous NO is known to regulate many adult tissues, its role during embryonic organogenesis and/or in mediating responses to teratogen exposure has not been explored. METHODS: We have examined here the presence of NO during normal chick embryonic organogenesis, and investigated the teratogenicity of NO through the application of sodium nitroprusside (SNP), which mimics NO overproduction, and NG‐monomethyl‐L‐arginine (L‐NMMA), which inhibits endogenous NOS activity. RESULTS: Topical treatment with SNP or L‐NMMA for 18 h resulted in morphological defects, specifically in the neural tube and somites, which corresponded to sites of altered apoptosis. The location of NO was histochemically correlated with the observed morphological defects. Coadministration of SNP or L‐NMMA with CO showed functional coregulation and interaction between NO and CO in chick embryonic development. CONCLUSIONS: Our results showed that regulation of NO is essential for normal axial development, that sites of altered NO expression correlate to those of altered apoptosis and dysmorphogenesis, and that CO coadministration resulted in a rectification of normal NO expression. Collectively, these results suggest that alteration in endogenous NO/CO signaling is responsible, at least in part, for the observed NO‐induced teratogenesis. © 2007 Wiley‐Liss, Inc.
Controlled Growth of SnO2 Hierarchical Nanostructures by a Multistep Thermal Vapor Deposition Process
Authors: Sun Shuhui , Meng Guowen , Zhang Gaixia , Masse Jean‐Philippe , Zhang Lide
Published: August 2007

Branched and sub‐branched SnO2 hierarchical architectures in which numerous aligned nanowires grew on the surface of nanobelt substrates have been obtained by a multistep thermal vapor deposition route. Branch size and morphology can be controlled by adjusting the temperature and duration of growth. The same approach was used to grow branched ZnO–SnO2 heterojunction nanostructures. In addition, the third level of SnO2 nanostructures was obtained by repeating the vapor deposition growth process. This technique provides a general, facile, and convenient approach for preparing even more complex nanoarchitectures, and should open up new opportunities for both fundamental research and applications, such as nanobelt‐based three‐dimensional nanodevices.
Photoinduced Electron Transfer on Aqueous Carbon Nanohorn–Pyrene–Tetrathiafulvalene Architectures
Authors: Pagona Georgia , Sandanayaka Atula S. D. , Maigné Alan , Fan Jing , Papavassiliou George C. , Petsalakis Ioannis D. , Steele Barry R. , Yudasaka Masako , Iijima Sumio , Tagmatarchis Nikos , Ito Osamu
Published: August 2007

Water‐soluble carbon‐nanohorn–tetrathiafulvalene (CNH‐TTF) nanoensembles were prepared by utilizing positively charged pyrene as an assembly medium and characterized by spectroscopy and electron microscopy. Electronic interactions within the nanoensemble were probed by optical spectroscopy, indicating electron transfer between the TTF units and CNHs after light illumination.
Controlled Synthesis, Growth Mechanism, and Properties of Monodisperse CdS Colloidal Spheres
Authors: Li Xin‐Hao , Li Ji‐Xue , Li Guo‐Dong , Liu Da‐Peng , Chen Jie‐Sheng
Published: August 2007

Highly monodisperse submicrometer CdS colloidal spheres (CSCS) with a controllable and tunable size (between 80 and 500 nm) have been synthesized through a facile solvothermal technique. Owing to the controllability of the reaction process, the growth mechanism of the colloidal spheres has been elucidated in detail. The whole growth process can be summarized as homogenous and slow nucleation of nanocrystals, formation of “cores” through 3D‐oriented attachment of nanocrystals, and further surface‐induced growth to monodisperse colloidal spheres through in situ formation and random attachment of additional nanocrystals. It has been demonstrated that the obtained CSCS colloidal particles are able to be assembled into films which show characteristic stop band gaps of photonic crystals. By using the CSCS as a template, Ag2S, Bi2S3, Cu2S, HgS, and Sb2S3 colloidal spheres, which are difficult to obtain directly, have also been prepared successfully through ion exchange.
Grafting Living Polymers onto Carbon Nanohorns
Authors: Mountrichas Grigoris , Pispas Stergios , Tagmatarchis Nikos
Published: August 2007

In the present paper we describe a new way for the covalent functionalization of carbon nanohorns by means of anionic polymerization with the “grafting to” approach. Polyisoprene homopolymers, as well as polyisoprene‐b‐polystyrene block copolymers have been attached on the surface of carbon nanohorns. The functionalized carbon nanostructures have been fully characterized by means of complementary spectroscopic techniques, electron microscopy, thermogravimetric analysis, and light scattering.
Parathyroid hormone‐related protein varies with sex and androgen status in nonsmall cell lung cancer
Authors: Montgrain Philippe R. , Quintana Rick , Rascon Yvette , Burton Douglas W. , Deftos Leonard J. , Casillas Andrea , Hastings Randolph H.
Published: August 2007

BACKGROUND.

In nonsmall cell lung cancer, tumor parathyroid hormone‐related protein (PTHrP) expression predicts longer survival in women but not in men. To explain the sex‐dependent survival effect, the authors proposed that hormonal influences decrease PTHrP in men versus women, that PTHrP inhibits tumor growth, and that the effect is greater in women than in men. The objectives of this study were to compare lung carcinoma PTHrP expression and carcinoma growth in male and female mice and to determine whether gonadal steroids regulate PTHrP in lung cancer cells.

METHODS.

Tumor PTHrP content was measured by immunoassay, and tumor burden was assessed with multiple measures in BEN squamous cell orthotopic lung carcinomas in athymic mice. In addition, lung adenocarcinoma PTHrP messenger RNA (mRNA) values determined by microarray analyses were compared between men and women. Cultured lung cancer cells were assayed for PTHrP after treatment with estradiol or R1881, a synthetic androgen.

RESULTS.

Lung carcinomas contained approximately 3 times more PTHrP in female mice than in male mice. Similarly, levels of PTHrP mRNA were significantly greater in adenocarcinomas from patients who were women than from patients who were men. Male mice had greater tumor burden than female mice. Androgen treatment reduced PTHrP in 3 lung cancer lines. Estradiol had no effect. Testosterone treatment also reduced lung carcinoma PTHrP in female mice.

CONCLUSIONS.

Lung carcinomas in females expressed more PTHrP than in males possibly because of negative regulation by androgens in males. Female mice with higher tumor PTHrP content had significantly less tumor burden than male mice, supporting the hypothesis that PTHrP inhibits tumor growth. Cancer 2007. © 2007 American Cancer Society.
Multifocal breast cancer in women ≤35 years old
Authors: Litton Jennifer K. , Eralp Yesim , Gonzalez‐Angulo Ana M. , Broglio Kristine , Uyei Anne , Hortobagyi Gabriel N. , Arun Banu
Published: August 2007

BACKGROUND.

The relation that multifocality at diagnosis had to survival in women < 35 years of age was evaluated.

METHODS.

Three hundred women seen at the M. D. Anderson Cancer Center between 1990 and 2002 were identified. Multifocality was defined as the presence of 2 or more foci of the same tumor clearly separated in the same breast. Patient characteristics and outcomes were tabulated and compared between uni‐ and multifocality. Survival outcomes were estimated with the Kaplan‐Meier product limit method and compared between groups with the log‐rank statistic. Cox proportional hazards models were fit to determine the association between multifocality and survival outcomes.

RESULTS.

The median age was 32 years (range, 17–35). There were 58 patients (19%) with multifocal disease. At a median follow‐up of 43.9 months there have been 101 deaths and 138 recurrences. Five‐year overall survival (OS) estimates were 69.7% (95% confidence interval [CI], 63.1%, 77.1%) for patients with unifocal disease and 67.3% (95% CI, 54.6%, 83.0%) for patients with multifocal disease (P = .70). Five‐year recurrence‐free survival (RFS) was 44.4% (95% CI, 37.1%, 53.2%) for patients with unifocal disease and 57.1% (5% CI, 43.3%, 75.4%) for patients with multifocal disease, (P = .36). Nuclear grade was found to be an independent predictor of OS and RFS (hazard ratio [HR], 2.92, 95% CI, 1.24–6.87; HR, 2.09, 95% CI, 1.13–3.83, respectively).

CONCLUSIONS.

Multifocality does not appear to influence prognosis in patients < 35 years of age. Nuclear grade continues to be an important prognostic factor for breast cancer in this age group. Cancer 2007. © 2007 American Cancer Society.
Expression of TGFβ type‐II receptor in association with markers of proliferation and apoptosis in premalignant lung lesions
Authors: Muñoz‐Antonia Teresita , Muro‐Cacho Carlos , Sharma Swati , Cantor Alan , Bepler Gerold
Published: August 2007

BACKGROUND.

Analysis of the early molecular abnormalities that play an oncogenic role in the progression of pulmonary neoplasia may lead to the identification of useful markers for early detection and prognosis. In normal squamous epithelium, transforming growth factor β (TGFβ) regulates cell growth and differentiation via specific membranous receptors and intracellular signaling molecules (Smads). The authors previously observed that, in head and neck squamous cell carcinoma, the expression of the TGFβ type II receptor (TβR‐II) decreases as tumors become less differentiated and more biologically aggressive.

METHODS.

In this pilot study of 48 premalignant bronchoepithelial lesions, the authors evaluated the expression of TβR‐II and 2 proliferation markers (Ki‐67 and MCM2), and the amount of early DNA fragmentation as evidence of apoptosis.

RESULTS.

The authors observed that the progression of premalignant lesions toward carcinoma in situ is accompanied by a decrease in TBR II expression and apoptosis and an increase in the expression of Ki‐67 and MCM2.

CONCLUSIONS.

These results suggested that the TGFβ pathway may be impaired early in the neoplastic process and that a combination of selected markers can provide a useful profile to detect preneoplastic changes in individuals at high risk for developing pulmonary carcinoma. Cancer 2007. © 2007 American Cancer Society.
Special Issue: Workshop on Grid Computing Portals (GCE 2005)
Authors: Thomas Mary
Published: August 2007

This article summarizes the outcome of a workshop held at Supercomputing 2005 that focused on grid computing portals and environments. This workshop is the first in a series of workshops planned in conjunction with the supercomputing meetings for the next few years. The intent of the workshop was to provide a venue for the community to share ideas, exchange experiences, and advance the field. Grid portals are faced with the challenge of providing simplified user interfaces to cyberinfrastructure, which results in the need for the portal developer to program to every layer in the cyberinfrastructure fabric and to develop unique solutions. This article summarizes the papers presented at this workshop. Copyright © 2007 John Wiley & Sons, Ltd.
Analysis of Classical and Quantum Paths for Deprotonation of Methylamine by Methylamine Dehydrogenase
Authors: Ranaghan Kara E. , Masgrau Laura , Scrutton Nigel S. , Sutcliffe Michael J. , Mulholland Adrian J.
Published: August 2007

The hydrogen‐transfer reaction catalysed by methylamine dehydrogenase (MADH) with methylamine (MA) as substrate is a good model system for studies of proton tunnelling in enzyme reactions—an area of great current interest—for which atomistic simulations will be vital. Here, we present a detailed analysis of the key deprotonation step of the MADH/MA reaction and compare the results with experimental observations. Moreover, we compare this reaction with the related aromatic amine dehydrogenase (AADH) reaction with tryptamine, recently studied by us, and identify possible causes for the differences observed in the measured kinetic isotope effects (KIEs) of the two systems. We have used combined quantum mechanics/molecular mechanics (QM/MM) techniques in molecular dynamics simulations and variational transition state theory with multidimensional tunnelling calculations averaged over an ensemble of paths. The results reveal important mechanistic complexity. We calculate activation barriers and KIEs for the two possible proton transfers identified—to either of the carboxylate oxygen atoms of the catalytic base (Asp428β)—and analyse the contributions of quantum effects. The activation barriers and tunnelling contributions for the two possible proton transfers are similar and lead to a phenomenological activation free energy of 16.5±0.9 kcal mol−1 for transfer to either oxygen (PM3‐CHARMM calculations applying PM3‐SRP specific reaction parameters), in good agreement with the experimental value of 14.4 kcal mol−1. In contrast, for the AADH system, transfer to the equivalent OD1 was found to be preferred. The structures of the enzyme complexes during reaction are analysed in detail. The hydrogen bond of Thr474β(MADH)/Thr172β(AADH) to the catalytic carboxylate group and the nonconserved active site residue Tyr471β(MADH)/Phe169β(AADH) are identified as important factors in determining the preferred oxygen acceptor. The protein environment has a significant effect on the reaction energetics and hence on tunnelling contributions and KIEs. These environmental effects, and the related clearly different preferences for the two carboxylate oxygen atoms (with different KIEs) in MADH/MA and AADH/tryptamine, are possible causes of the differences observed in the KIEs between these two important enzyme reactions.
Investigations on the growth, optical behaviour and factor group of an NLO crystal: L‐alanine alaninium nitrate
Authors: Aravindan A. , Srinivasan P. , Vijayan N. , Gopalakrishnan R. , Ramasamy P.
Published: August 2007

Amino acid family crystals exhibit excellent nonlinear and electro‐optical properties. L‐alanine alaninium nitrate (LAAN) single crystal belonging to the amino acid group was grown by slow cooling solution growth technique. The High resolution X‐ray diffraction (HRXRD), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, UV‐Vis., Photoluminescence (PL) and Factor group analyses were carried out. The factor group analysis reveals 183 internal vibrations for the title compound. The second harmonic generation property was tested by Kurtz‐Perry powder technique. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis and Reactivity of Alkenyl‐Substituted Zirconocene Complexes and Their Application as Olefin Polymerisation Catalysts
Authors: Gómez‐Ruiz Santiago , Polo‐Cerón Dorian , Prashar Sanjiv , Fajardo Mariano , Antiñolo Antonio , Otero Antonio
Published: August 2007

The zirconocene complexes [Zr(η5‐C5H5){η5‐C5H4(CMe2CH2CH2CH=CH2)}Cl2] (4) and [Zr{η5‐C5H4(CMe2CH2CH2CH=CH2)}2Cl2] (5) were synthesised from the reaction of the lithium derivative [Li{C5H4(CMe2CH2CH2CH=CH2)}] (1) with [Zr(η5‐C5H5)Cl3] or ZrCl4, respectively. The ansa‐zirconocene complex [Zr{Me2Si(η5‐C5Me4)(η5‐C5H3{CMe2CH2CH2CH=CH2})}Cl2] (6) was obtained from the reaction of the lithium precursor [Li2{Me2Si(η5‐C5Me4)(η5‐C5H3{CMe2CH2CH2CH=CH2})}] (3) with zirconium tetrachloride. Catalytic hydrogenation of 4–6 gave the zirconocene complexes [Zr(η5‐C5H5){η5‐C5H4(CMe2CH2CH2CH2CH3)}Cl2] (7), [Zr{η5‐C5H4(CMe2CH2CH2CH2CH3)}2Cl2] (8) and [Zr{Me2Si(η5‐C5Me4)(η5‐C5H3{CMe2CH2CH2CH2CH3})}Cl2] (9), respectively. Hydroboration of 4–6 with 9‐BBN (9‐borabicyclo[3.3.1]nonane) yielded [Zr(η5‐C5H5){η5‐C5H4(CMe2CH2CH2CH2CH2BC8H14)}Cl2] (10), [Zr{η5‐C5H4(CMe2CH2CH2CH2CH2BC8H14)}2Cl2] (11) and[Zr{Me2Si(η5‐C5Me4)(η5‐C5H3{CMe2CH2CH2CH2CH2BC8H14})}Cl2] (12), respectively, and the catalytic hydrosilylation of 4–6 with SiHMe2Cl gave [Zr(η5‐C5H5){η5‐C5H4(CMe2CH2CH2CH2CH2SiMe2Cl)}Cl2] (13), [Zr{η5‐C5H4(CMe2CH2CH2CH2CH2SiMe2Cl)}2Cl2] (14) and [Zr{Me2Si(η5‐C5Me4)(η5‐C5H3{CMe2CH2CH2CH2CH2SiMe2Cl})}Cl2] (15), respectively. The dinuclear complex [Cl2Zr{Me2Si(η5‐C5Me4)(η5‐C5H3{CMe2(CH2)4SiMe2OSiMe2(CH2)4Me2C}η5‐C5H3)(η5‐C5Me4)SiMe2}ZrCl2] (16) was obtained upon controlled hydrolysis of 15. The zirconocene compounds were tested as catalysts in the polymerisation of ethylene and propylene. Isotactic polypropylene with [mmmm] pentads of the order of 75 % were obtained with the ansa‐zirconocene catalysts, whereas the unbridged metallocene catalysts produced atactic polypropylene. The molecular structures of 4 and 5 were determined by single‐crystal X‐ray diffraction studies.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
In Vitro Formation of Nanocrystalline Carbonate Apatite – A Structural and Morphological Analogue of Atherosclerotic Plaques
Authors: Olsson Lars‐Fride , Sandin Karin , Odselius Rolf , Kloo Lars
Published: August 2007

The in vitro formation of carbonate apatite in solutions with ion concentrations comparable to those in human serum was studied. The composition and morphology of the resulting apatite precipitate displayed a hierarchical assembly of elongated plate‐shaped nanocrystals of carbonate apatite analogous to previously characterized bioapatites formed in vivo. The main conclusion is that so‐called bioapatites may form in vitro and that precipitation inhibitors most likely are essential for the prevention of spontaneous calcification at normal human serum ion concentrations. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Trans fatty acid content of foods and intake levels in France
Authors: Laloux Laurent , du Chaffaut Laure , Razanamahefa Landy , Lafay Lionel
Published: August 2007

As a preliminary for recommended trans fatty acid (TFA) consumption levels as regards health, it was essential to estimate the TFA intake level. Recent results of TFA content of foods were collected, and the total TFA, 18:1 TFA, 18:2 TFA and total conjugated linoleic acid (CLA) compositions were recorded for around 900 food items. These results were combined with the latest consumption data in France in order to update the TFA intake level in France. Average daily total TFA intake was about 3.0 and 3.4 g/day in boys and men, and about 2.7 and 2.8 g/day in girls and women, respectively. The same tendency was observed for TFA 18:1 intake (boys 2.1 g/day, men 2.4 g/day, girls 1.9 g/day, women 2.0 g/day) and for TFA 18:2 (boys 0.2 g/day, men 0.24 g/day, girls 0.18 g/day, women 0.18 g/day). For CLA, the mean daily intake was higher in males than in females for both adults (0.21 g/day vs. 0.18 g/day) and children (0.18 g/day vs. 0.17 g/day). Foods of animal origin (dairy products and meat from ruminants) were the main contributors of total TFA, accounting for 60% of the identified TFA. Dairy products were the main contributors of total CLA, accounting for 70% of the identified CLA. In other words, manufactured pastries, biscuits, ready meals and chocolate bars accounted for 40% of total TFA and 30% of CLA.
Organoborane Reagents in the C‐Alkylation of Aromatic Aldimines
Authors: Valpuesta María , Muñoz Carmen , Díaz Amelia , Suau Rafael , Torres Gregorio
Published: August 2007

The reaction of an aldimine with dicyclohexylboron chloride in the presence of hydrogen peroxide gives N‐[cyclohexyl(aryl)methyl]arylamines 2 in good yields via oxidized imine–borane complexes. The amines can also be obtained by a three‐component reaction involving an arenecarbaldehyde, an arylamine and a dialkylchloroborane reagent. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Synthesis of 1,1,3‐Trisubstituted Naphtho[2,3‐c]pyran‐5,10‐dione Derivatives as Potential Redox Switches
Authors: Shie Tien‐Lan , Lin Chi‐Hui , Lin Shih‐Lun , Yang Ding‐Yah
Published: August 2007

Five 1,1,3‐trisubstituted naphtho[2,3‐c]pyran‐5,10‐dione derivatives were designed and synthesized in five steps from 2‐acetyl‐1,3‐indandione. Prepared quinones 6a–e instantly changed from either red or blue to yellow or orange red, when treated with sodium borohydride in methanol. The resulting reduced hydroquinones 9a–e reverted to their original colors within a few minutes after the reducing agent was consumed or removed. Whereas no fluorescence of blue quinone 6e was detected prior to reduction, reduced hydroquinone 9e emitted red fluorescence with a quantum yield of 0.07.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Synthesis of Homo‐ and Heteroditopic 8‐Hydroxyquinoline Ligands
Authors: Albrecht Markus , Osetska Olga , Fröhlich Roland
Published: August 2007

The Claisen rearrangement is a versatile reaction for the preparation of either isobutenylidene‐ or n‐butenylidene‐bridged bis(8‐hydroxyquinoline) ligands for supramolecular chemistry. The Hiratani–double‐Claisen rearrangement of the appropriate isobutenylidene bis(aryl) ethers enables the formation of either symmetrical or unsymmetrical ligand systems with two tridentate or one bi‐ and one tridentate quinoline‐based chelating units. Claisen rearrangement of quinoline allyl ether followed by Grubbs metathesis affords the symmetric ligand with an elongated spacer between the chelates. The described ligands are of interest for the self‐assembly of homo‐ and heterodinuclear near‐IR‐emitting lanthanide complexes.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Iron‐Catalyzed Four‐Component Reaction for the Synthesis of Protected Primary Amines
Authors: Yang Bai‐Ling , Tian Shi‐Kai
Published: August 2007

The first catalytic four‐component reaction (4CR) of carbonyl compounds with alkyl chloroformate, HMDS and Et3SiH has been developed to produce protected primary amines by a novel tandem nitrogen protection/direct reductive amination of carbonyl compounds. In the presence of 5 mol‐% of an iron(II) salt, a wide variety of aldehydes and ketones were transformed into their corresponding protected primary amines in good to excellent yields under “pure” multicomponent reaction (MCR) conditions. This chemistry was further extended to masked carbonyl compounds such as acetals, ketals, and vinyl ethers. When compared with previous methods to prepare protected primary amines from a large excess of ammonia or ammonium salts, this 4CR not only saved at least one step of synthetic manipulation, but also utilized nearly stoichiometric nitrogen and hydrogen sources and avoided the formation of (protected) secondary amines. Additional advantages of this protocol include broader substrate scope, the use of an inexpensive and environmentally friendly catalyst, and mild reaction conditions.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
CE with electrochemical detection for investigation of label‐free recognition of amino acid amides by guanine‐rich DNA aptamers
Authors: Li Tao , Du Yan , Li Bingling , Dong Shaojun
Published: August 2007

In this work, we report a simple and effective investigation into adaptive interactions between guanine‐rich DNA aptamers and amino acid amides by CE with electrochemical (EC) detection. Argininamide (Arm) and tyrosinamide (Tym) were chosen as model molecules. On a copper electrode, Arm generated a good EC signal in 60 mM NaOH at 0.7 V (vs Ag/AgCl), while Tym was detected well on a platinum electrode at 1.3 V in 20 mM phosphate of pH 7.0. Based on their EC properties, the ligands themselves were used as indicators for the adaptive interactions investigated by CE‐EC, making any step of labeling and/or modification of aptamers with indicators exempted. Hydrophilic ionic liquid was used as an additive in running buffer of CE to improve the sensitivity of Arm detection, whereas the additive was not used for Tym detection due to its negative effect. Two guanine‐rich DNA aptamers were used for molecular recognition of Arm and Tym. When the aptamers were incubated with ligands, they bound the model molecules with high affinity and specificity, reflected by obvious decreases in the signals of ligands but no changes in those of the control molecules. However, the ligands were hardly affected by the control ssDNAs after incubation. The results revealed the specific recognition of Arm and Tym by the aptamers. The mechanisms for binding model molecules by aptamers were discussed. Not as expected, these aptamers were not to form the G‐quartets, which were generally responsible for binding the ligands when the guanine‐rich aptamers were used.
Comprehensive profiling of the complex dendrimeric contrast agent Gadomer using a combined approach of CE, MS, and CE‐MS
Authors: Vetterlein Kai , Bergmann Ulf , Büche Karlo , Walker Martina , Lehmann Jochen , Linscheid Michael W. , Scriba Gerhard K. E. , Hildebrand Michael
Published: August 2007

The complex dendrimeric contrast agent Gadomer has been comprehensively characterized using various mass spectrometric techniques in combination with capillary electrophoresis. The analytical challenges arising from the structure of this analyte, e.g., the presence of a complex isotopic pattern originating from multiple gadolinium chelates could be overcome using this combined approach. Results obtained from initial MALDI‐TOF‐MS measurements could subsequently be complemented and confirmed by CE‐ESI‐TOF‐MS measurements. Furthermore, high resolution Fourier transform‐ion cyclotron resonance‐MS (FT‐ICR‐MS) as a stand alone technique and in combination with CE was performed to obtain mass spectra of high mass accuracy and resolution of various impurities and related dendrimers present in low concentrations in several Gadomer batches. The profile of related dendrimers and impurities of lower molecular weight present in Gadomer could be elucidated and variances in the pattern of related dendrimers present in batches obtained via different synthetic routes could be detected. The qualitative analysis of Gadomer using MS techniques in combination with CE provides the fundamental basis for a framework of analytical methodologies for the characterization of Gadomer. By designing such a framework of methodologies the challenges associated with the introduction of dendrimers into the clinical stage may be overcome and the reproducible quality and safety of these innovative products can be ensured.
Prenatal diagnosis of atrial septal aneurysm
Authors: Hung Jeng‐Hsiu , Lu Jen‐Her , Hung Chia‐Yi Selena
Published: August 2007

We report the prenatal diagnosis of fetal atrial septal aneurysm based on the observation of a fluttering flap in the left atrium. The aneurysm was associated with an interatrial communication. In a 4‐chamber view, separate arms of the aneurysm could be seen contracting in and extending out in response to the fetal cardiac cycle, giving the fluttering appearance of a jellyfish. The aneurysm disappeared 1 month after birth with no complications. The findings in this case indicate that isolated atrial septal aneurysm is a natural transient phase of spontaneous closure of the foramen ovale during normal fetal development. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
Doppler sonography in the diagnosis of round ligament varicosities during pregnancy
Authors: Nguyen Quyen H. , Gruenewald Simon M.
Published: August 2007

Round ligament varicosities during pregnancy are an important differential diagnosis of complicated inguinal hernias and have been reported only rarely. Diagnosis is reassuring and may prevent unnecessary surgical exploration. We describe a case of round ligament varicosities presenting during pregnancy that was readily diagnosed with Doppler sonography. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
Ductus venosus blood flow resistance and congenital heart defects in the second trimester
Authors: Hung Jeng Hsiu , Fu Chong Yau , Lu Jen‐Her , Hung Chia‐Yi Selena
Published: August 2007

Purpose

To study the association between fetal cardiac defects and the presence of abnormal blood flow resistance of the ductus venosus during the second trimester of pregnancy.

Methods

This retrospective case–control study included 72 pregnancies with fetal cardiac anomalies and 267 normal pregnancies. In fetuses with cardiac anomalies, Doppler velocimetry resistances of the ductus venosus were serially determined prior to birth. The Doppler velocimetry resistances obtained from fetuses with cardiac anomalies were in turn compared with median values derived from 267 normal pregnancies to compensate for biometric bias due to gestational age.

Results

Among the 72 pregnancies with fetal cardiac anomalies, 26 fetuses showed isolated congenital heart disease (CHD) without nonimmune fetal hydrops (NIFH) (group A), 10 fetuses showed isolated CHD with severe heart defects, including atrioventricular valve insufficiency and consecutive cardiogenic NIHF (group B), and 36 fetuses showed chromosomal abnormalities, nonchromosomal extracardiac malformations, noncardiogenic NIHF, and fetal growth restriction summarized as nonisolated CHD (group C). Based on the pulsatility index for the vein of the ductus venosus, the area under the receiver operating characteristic (ROC) curves was 0.71, 0.73, and 0.86 for groups A, B, and C, respectively.

Conclusion

In the 36 fetuses from group C, increased pulsatility index for vein of the ductus venosus (DVPIV) yielded a significant area under the ROC curve (0.86) with a sensitivity of 0.78 and a specificity of 0.78. Increased DVPIVs during the second trimester of pregnancy are highly correlated with fetal cardiac anomalies associated with chromosomal and extracardiac anomalies. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
Geopolitics and the effect of foreign aid on economic growth: 1970–2001
Authors: Headey Derek
Published: August 2007

Previous aid effectiveness research often claims that foreign aid has been unsuccessful in increasing growth rates. This result could be due either to methodological weaknesses, or to genuine aid efficiency losses. Empirically, the author finds that once the best available techniques are employed, aid has a significant but moderate average effect on growth over the period 1970–2001. A promising explanation of why the estimated returns to aid are not larger is that bilateral aid had no significant effect on growth during the Cold War (pre‐1990), but had a significant and sizeable effect thereafter. In contrast, multilateral aid seems to have had sizeable and significant effects throughout. These results imply that the negative conclusions drawn by earlier research should be interpreted in their proper historical context, rather than as a necessary condemnation of current aid effectiveness. Copyright © 2007 John Wiley & Sons, Ltd.
Quantitative mouse model of implant‐associated osteomyelitis and the kinetics of microbial growth, osteolysis, and humoral immunity
Authors: Li Dan , Gromov Kirill , Søballe Kjeld , Puzas J. Edward , O'Keefe Regis J. , Awad Hani , Drissi Hicham , Schwarz Edward M.
Published: August 2007

Although osteomyelitis (OM) remains a serious problem in orthopedics, progress has been limited by the absence of an in vivo model that can quantify the bacterial load, metabolic activity of the bacteria over time, immunity, and osteolysis. To overcome these obstacles, we developed a murine model of implant‐associated OM in which a stainless steel pin is coated with Staphylococcus aureus and implanted transcortically through the tibial metaphysis. X‐ray and micro‐CT demonstrated concomitant osteolysis and reactive bone formation, which was evident by day 7. Histology confirmed all the hallmarks of implant‐associated OM, namely: osteolysis, sequestrum formation, and involucrum of Gram‐positive bacteria inside a biofilm within necrotic bone. Serology revealed that mice mount a protective humoral response that commences with an IgM response after 1 week, and converts to a specific IgG2b response against specific S. aureus proteins by day 11 postinfection. Real‐time quantitative PCR (RTQ‐PCR) for the S. aureus specific nuc gene determined that the peak bacterial load occurs 11 days postinfection. This coincidence of decreasing bacterial load with the generation of specific antibodies is suggestive of protective humoral immunity. Longitudinal in vivo bioluminescent imaging (BLI) of luxA‐E transformed S. aureus (Xen29) combined with nuc RTQ‐PCR demonstrated the exponential growth phase of the bacteria immediately following infection that peaks on day 4, and is followed by the biofilm growth phase at a significantly lower metabolic rate (p < 0.05). Collectively, these studies demonstrate the first quantitative model of implant‐associated OM that defines the kinetics of microbial growth, osteolysis, and humoral immunity following infection. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J. Orthop Res 26:96–105, 2008
In vivo mechanical condition plays an important role for appearance of cartilage tissue in ES cell transplanted joint
Authors: Nakajima Masaaki , Wakitani Shigeyuki , Harada Yasuji , Tanigami Akira , Tomita Naohide
Published: August 2007

The objective of this study was to evaluate the effects of the mechanical environment on the formation of cartilage tissue in transplanted embryonic stem (ES) cells. Full‐thickness osteochondral defects were created on the patella groove of SD rats, and ES cells (CCE ES cells obtained from 129/Sv/Ev mice and Green ES FM260 ES cells obtained from 129SV [D3] ‐ Tg [NCAG‐EGFP] CZ—001–FM260Osb mice) were transplanted into the defects embedded in collagen gel. The animals were randomly divided into either the joint‐free group (JF group) or the joint‐immobilized group (JI group) for 3 weeks after a week postoperatively. The results showed that cartilage‐like tissue formed in the defects of the JF group whereas large teratomatous masses developed in the defects of the JI group. Some parts of the cartilage‐like tissue and the teratomatous masses were positively stained with immunostain for GFP when the Green ES FM260 ES cells were transplanted. It is suggested that the environment plays an important role for ES cells in the process of repairing cartilage tissue in vivo. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:10–17, 2008
Multilineage differentiation of porcine bone marrow stromal cells associated with specific gene expression pattern
Authors: Zou Lijin , Zou Xuenong , Chen Li , Li Haisheng , Mygind Tina , Kassem Moustapha , Bünger Cody
Published: August 2007

There are increasing reports regarding differentiation of bone marrow stromal cells (BMSC) from human and various species of animals including pigs. The phenotype and function of BMSC along a mesenchymal lineage differentiation are well characterized by specific transcription factors and marker genes. However, it is not fully clear whether multilineage differentiation (osteogenesis, chondrogenesis, and adipogenesis) of BMSC is associated with a specific gene expression pattern. In the present study, we investigated the gene expression pattern of representative transcription factors and marker genes along those three mesenchymal lineages during a particular lineage differentiation of porcine BMSC by means of real‐time PCR measurement. In an osteogenic medium, the mRNA levels of cbfa1, osterix, alkaline phosphatase, type 1 collagen, osteonectin, bone sialoprotein, and osteocalcin were induced stepwise. Meanwhile, sox9, specific to chondrogenic differentiation, was inhibited but not PPARγ2 specific to adipogenic differentiation. In an adipogenic medium, adipogenic differentiation was confirmed by upregulation of PPARγ2 and aP2 and downregulation of osteogenic genes and sox9. Chondrogenic differentiation was induced in cell pellet culture by expression of sox9, type 2 collagen, and aggrecan. Cbfa1 and PPARγ2 were inhibited in chondrogenic medium. These results indicate that the differentiation potential of BMSC to a particular mesenchymal lineage relies upon specific gene expression pattern, namely upregulation of genes specific for this lineage and suppression of other lineage differentiation. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:56–64, 2008
Neuromuscular adaptations and correlates of knee functionality following ACL reconstruction
Authors: Bryant Adam L. , Kelly Jason , Hohmann Erik
Published: August 2007

The objective of this research was to examine the dynamic restraint mechanism by establishing the neuromuscular characteristics of lower extremity muscles in anterior cruciate ligament reconstruction (ACLR) subjects. This study also investigated neuromuscular variables that relate to post‐ACLR functional outcome. Thirteen patients having undergone ACLR using the bone patella tendon bone graft at least 6 months prior participated in this study. Knee functionality (0‐ to 100‐point scale) was rated using the Cincinnati Knee Rating System. The median frequency of the electromyographic (EMG) recordings from the vastus medialis (VM) and vastus lateralis (VL) muscles together with the isokinetic quadriceps torque generated in 10° intervals between 80° and 10° knee flexion was determined for the noninvolved and involved limbs. Lower limb musculotendinous stiffness was also assessed for the noninvolved and involved limbs. Limb symmetry indexes were calculated for each of the physiological measures. Compared to the noninvolved limb, the median frequency of the EMG from the involved limb VM and VL muscles was significantly lower as was the quadriceps torque generated at the seven knee flexion intervals. In contrast, musculotendinous stiffness was significantly higher in the involved lower limb compared to the noninvolved limb. Significant, moderate correlations were identified between knee functionality and symmetry indexes for all variables except for the isokinetic quadriceps torque produced between 80°–70° and 20°–10° knee flexion. More functional ACLR subjects demonstrated enhanced motor unit recruitment reflective of less quadriceps muscle fiber atrophy together with increased quadriceps strength and musculotendinous stiffness of the lower limb musculature. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:126–135, 2008
Effect of osteogenic protein‐1 on the matrix metabolism of bovine tendon cells
Authors: Yamada Michiaki , Akeda Koji , Asanuma Kunihiro , Thonar Eugene J.‐M.A. , An Howard S. , Uchida Atsumasa , Masuda Koichi
Published: August 2007

Tendon rupture is a common sports injury in adults. However, the mechanical properties of repair tissue are inferior to those of normal tissue. To accelerate tendon healing, an in vivo approach using growth factors has been applied and has shown evidence for the efficacy of biological stimulation of the repair process. Recombinant human osteogenic protein‐1 (rhOP‐1) has been shown to be effective in stimulating matrix production by various connective tissues. To test the effect of rhOP‐1 on the matrix metabolism of tendon cells in vitro, bovine tendon cells were cultured in monolayer with various doses of rhOP‐1 for 7 days. The addition of rhOP‐1 to cell culture media resulted in significant increases in cell proliferation, DNA content, and the synthesis of proteoglycans (PGs) and collagen, compared to control cultures. The relative percentage of large PGs in the OP‐1 culture was higher than that in the control culture. In conclusion, we show for the first time that rhOP‐1 stimulates the proliferation of tendon cells and their ability to synthesize and accumulate PGs and collagen in their extracellular matrix. These biological properties may be used in the tissue‐engineering of tendon tissues. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:42–48, 2008
Locomotor skills and balance strategies in children with internal rotations of the lower limbs
Authors: Mallau Sophie , Mesure Serge , Viehweger Elke , Jacquemier Michel , Bollini Gérard , Assaiante Christine
Published: August 2007

The purpose of this study was to investigate the functional effects of a structural deformation, internal rotations (IR) of the lower limbs, on upper body balance strategies used during locomotion in 5–6 year‐old and 7–10 year‐old children. Balance control was examined in terms of rotation around the longitudinal axis in horizontal plane (yaw) and around the sagittal axis in a frontal plane (roll). Kinematics of foot, pelvis, shoulder, and head rotations were measured with an automatic optical TV image processor and used to calculate angular dispersions and segmental stabilizations. Older children with IR showed a lower gait velocity, particularly in difficult balance conditions than typically developing (TD) children. In younger children, the effect of the local biomechanical deficit remained limited to the lower limbs and did not affect upper body coordination. By contrast, in older children with IR, the development of head stabilization in space was affected. This was demonstrated by an “en bloc” instead of an articulated mode of head‐trunk unit systematically adopted by the control group. As pelvic stabilization remains the main reference frame to organize balance control in older children with IR, we conclude that the structural deformity of the legs affect and possibly delay the acquisition of the head stabilization in space strategy. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:117–125, 2008
Clinical outcome and genotype in patients with hereditary multiple exostoses
Authors: Jäger Marcus , Westhoff Bettina , Portier Sebastian , Leube Barbara , Hardt Karin , Royer‐Pokora Brigitte , Goßheger Georg , Krauspe Rüdiger
Published: August 2007

Hereditary multiple exostoses (HME) is an autosomal dominant skeletal disorder with a wide spectrum of clinical manifestations. In 52 out of 60 individuals from HME+ families, exostoses became clinically apparent. In this study, the clinical and radiological outcome of these 52 HME patients (19 families) was investigated by medical history, clinical examination, and radiographs. In addition to correlating phenotype with genotype, a linkage/exclusion analysis was performed in 35 HME patients. We found several correlations between HME genes (EXT1, EXT2) and phenotype. Compared to EXT2‐linkage, female individuals with EXT1‐linkage were smaller in stature. Patients with EXT1‐linkage and patients with undetermined linkage (EXT?) were more severely affected, underwent more surgeries, and showed a higher number of exostoses at follow‐up. Moreover, we found an increased phenotype risk for limb shortening for EXT1‐ and EXT?‐linkage. This study corresponds to data of other investigators who showed that EXT1 mutations are associated with a more severe phenotype than other EXT forms. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1541–1551, 2007