bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

AbstractBACKGROUND.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

AbstractThis 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

AbstractThe 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

AbstractAmino 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

AbstractThe 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

AbstractThe 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

AbstractAs 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

AbstractThe 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

AbstractFive 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

AbstractThe 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

AbstractThe 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

AbstractIn 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

AbstractThe 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

AbstractWe 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

AbstractRound 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

AbstractPurposeTo 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.MethodsThis 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.ResultsAmong 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.ConclusionIn 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

AbstractPrevious 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

AbstractAlthough 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