bluuebunny/crossref_metadata_2025 huggingface dataset:
Sodium‐dependent vitamin C transporter 2 (SVCT2) is necessary for the uptake of L‐ascorbic acid into Schwann cells
Authors: Gess Burkhard , Lohmann Christina , Halfter Hartmut , Young Peter
Published: August 2009

Ascorbic acid has been shown to be an essential component for in vitro myelination and to improve the clinical and pathological phenotype of a mouse model of Charcot–Marie‐tooth disease 1A. The mechanism of ascorbic acid uptake into peripheral nerves, however, has not been addressed so far. Hence, we studied the expression and activity of sodium‐dependent vitamin C transporters 1 and 2 (SVCT1 and 2) in the peripheral nervous system. Using immunohistochemistry, immunoblotting, and reverse transcription PCR, we could show that SVCT1 and 2 were differentially expressed in myelinated peripheral nerve fibers and Schwann cell (SC) cultures. SVCT1 was expressed at very low levels confined to the axons, whereas SVCT2 was highly expressed both in the axons and in the SCs. SVCT2 was localized particularly in SC compartments of uncompacted myelin. Uptake assays using 14C‐labeled ascorbic acid showed transport of ascorbic acid into SC cultures. Ascorbic acid transport was dependent on the concentration of sodium, magnesium, and calcium in the extracellular medium. Treatment with the flavonoid phloretin, a known inhibitor of SVCT1 and 2, and specific RNA interference with SVCT2 caused significant reductions in ascorbic acid uptake into SCs. Phloretin‐inhibited uptake of ascorbic acid was further shown in freshly dissected, cell‐culture‐naïve rat sciatic nerves. These results provide evidence for the first time that uptake of ascorbic acid in the peripheral nervous system is crucially dependent on the expression and activity of SVCT2. © 2009 Wiley‐Liss, Inc.
Head and neck cancer radiosensitization by the novel poly(ADP‐ribose) polymerase inhibitor GPI‐15427
Authors: Khan Khurram , Araki Koji , Wang Daiyou , Li Guayan , Li Xin , Zhang Jie , Xu Weizheng , Hoover Randall K. , Lauter Susan , O'Malley Bert , Lapidus Rena G. , Li Daqing
Published: August 2009

Background

In this study, we tested the ability of a novel poly(adenosine diphosphate ribose) polymerase (PARP) inhibitor, 10‐(4‐methyl‐piperazin‐1‐ylmethyl)‐2H‐7‐oxa‐1,2‐diaza‐benzo[de]‐anthracen‐3‐one (GPI‐15427), to enhance the effect of radiotherapy in a xenograft model of human head and neck squamous cell carcinoma (HNSCC).

Methods

Human xenograft HNSCC tumors were established in female nude mice: animals were treated with orally administered GPI‐15427 at varied doses prior to tumor irradiation. In vitro and in vivo apoptosis analyses and neutral single‐cell gel electrophoresis (comet) assay were performed, with the “tail moment” calculated to evaluate DNA double‐strand break damage.

Results

Orally administered GPI‐15427 given before radiation therapy significantly reduced tumor volume, and cells demonstrated significantly elevated mean tail moments (indicative of DNA damage) and enhanced apoptosis both in vitro and in vivo, compared with radiation‐alone and control groups.

Conclusions

Use of the PARP‐1 inhibitor GPI‐15427 induced significant sensitization to radiotherapy, representing a promising new treatment in the management of HNSCC. © 2009 Wiley Periodicals, Inc. Head Neck, 2010
Dual priming oligonucleotide–based multiplex PCR analysis for detection of BRAFV600E mutation in FNAB samples of thyroid nodules in BRAFV600E mutation–prevalent area
Authors: Kwak Jin Young , Kim Eun‐Kyung , Kim Jong‐Kee , Han Jeong‐Hyun , Hong Soon Won , Park Tae Sung , Choi Jong Rak
Published: August 2009

Background.

To evaluate the diagnostic value of dual priming oligonucleotide (DPO)–based multiplex polymerase chain reaction (PCR) for the detection of BRAFV600E mutations in ultrasound‐guided fine‐needle aspiration biopsy (US‐FNAB) of thyroid nodules.

Methods.

Our institutional review board approved this retrospective study, and informed consent was not required from patients. The 130 patients underwent US‐FNAB to evaluate BRAF status in thyroid nodules. In FNAB washouts, DPO‐based multiplex PCR, direct DNA sequencing, and PCR–restriction fragment length polymorphism (RFLP) were used to detect BRAFV600E. The diagnostic performance of these methods was calculated. We compared cytologic results by BRAF status.

Results.

Diagnostic accuracy and sensitivity were highest when screening with DPO‐based multiplex PCR. BRAFV600E positivity was a useful marker at thyroid nodules with “suspicious for papillary thyroid carcinoma” or “inadequate” cytological result.

Conclusions.

DPO‐based multiplex PCR may be an alternative to direct DNA sequencing because of its high sensitivity, high accuracy, and simplicity. BRAFV600E may be a useful additional diagnostic marker in BRAFV600E‐prevalent areas. © 2009 Wiley Periodicals, Inc. Head Neck, 2010
In vivo and in vitro models of ionizing radiation to the vocal folds
Authors: Saltman Benjamin , Kraus Dennis H. , Szeto Hazel , Parashar Bhupesh , Ghossein Ronald , Felsen Diane , Branski Ryan C.
Published: August 2009

Background

Radiation therapy (RT) to the head and neck often results in damage to the vocal folds (VF) and surrounding structures. Characterization and treatment of these sequelae is limited, likely due to the lack of experimental models.

Methods

Larynges from rats exposed to 2 fractionation schedules (40 Gy total) were analyzed histologically. In vitro, reactive oxygen species (ROS) synthesis, and transcription of select genes associated with ROS, inflammation, and fibrosis were examined in VF fibroblasts after single‐dose radiation.

Results

Although radiation‐induced histologic alterations are made to VF architecture, 1 fractionation schedule was accompanied by significant morbidity and mortality. In vitro, radiation increased ROS synthesis and inflammatory and profibrotic gene expression.

Conclusion

Our data suggest that hyperfractionated RT is more tolerable. Utilizing this model, RT‐induced histologic aberrations are made to the VF mucosa. In addition, a relationship between radiation, ROS, and inflammatory and fibrotic gene expression was observed in vitro. © 2009 Wiley Periodicals, Inc. Head Neck, 2010
Land of addicts? an empirical investigation of habit‐based asset pricing models
Authors: Chen Xiaohong , Ludvigson Sydney C.
Published: August 2009

This paper studies the ability of a general class of habit‐based asset pricing models to match the conditional moment restrictions implied by asset pricing theory. We treat the functional form of the habit as unknown, and estimate it along with the rest of the model's finite dimensional parameters. Using quarterly data on consumption growth, assets returns and instruments, our empirical results indicate that the estimated habit function is nonlinear, that habit formation is better described as internal rather than external, and the estimated time‐preference parameter and the power utility parameter are sensible. In addition, the estimated habit function generates a positive stochastic discount factor (SDF) proxy and performs well in explaining cross‐sectional stock return data. We find that an internal habit SDF proxy can explain a cross‐section of size and book‐market sorted portfolio equity returns better than (i) the Fama and French (1993) three‐factor model, (ii) the Lettau and Ludvigson (2001b) scaled consumption CAPM model, (iii) an external habit SDF proxy, (iv) the classic CAPM, and (v) the classic consumption CAPM. Copyright © 2009 John Wiley & Sons, Ltd.
Hox genes of the Japanese eel Anguilla japonica and Hox cluster evolution in teleosts
Authors: Guo Baocheng , Gan Xiaoni , He Shunping
Published: August 2009

Compared with other diploid teleosts (2n=48), anguilloid fish have a specialized karyotype (2n=38) and remarkable morphological variation, and represent one basal group species of teleosts. To investigate the Hox gene/cluster inventory in basal teleosts, a PCR‐based survey of Hox genes in the Japanese eel (Anguilla japonica) was conducted with both gene‐specific and homeobox‐targeted degenerate primers. Our data provide evidence that at least 34 distinct Hox genes exist in the Japanese eel genome and that they represent eight Hox clusters. Duplication of Hox genes in the Japanese eel appears to be the result of the fish‐specific genome duplication (FSGD) event. The Japanese eel shared the FSGD event with other teleosts such as zebrafish and pufferfish. A member of Hox paralog group one (HoxA1b) was preserved in the Japanese eel but was lost in other teleosts. Available Hox data revealed that the Hox cluster evolved distinctly in different teleost lineages. All duplicated Hox clusters were retained after the FSGD event in basal teleosts like in the Japanese eel, whereas crown teleosts lost one cluster (HoxCb or HoxDb). Based on current teleostean phylogeny, the HoxDb cluster was lost independently in the teleost lineages Otocephala and Euteleostei. J. Exp. Zool. (Mol. Dev. Evol.) 314B:135–147, 2010. © 2009 Wiley‐Liss, Inc.
Radiosynthesis of [3H]‐ABP688 using [3H]‐methyl nosylate: a non‐volatile alternative methylating agent
Authors: Li Pixu , Olszewski John D.
Published: August 2009

Tritiated ABP688 was synthesized from desmethyl ABP688 with [3H]‐methyl nosylate in high radiochemical yield. The results demonstrate that [3H]‐methyl nosylate is a good alternative methylating agent for radiosynthesis. Copyright © 2009 John Wiley & Sons, Ltd.
[14C]Dimethyltitanocene and [14C]Methyl(methyltrimethylsilyl) titanocene–Reagents for the [14C]olefination of carbonyl compounds: synthesis of [14C]Aprepitant
Authors: Wallace M. A. , Dean D. C. , Melillo D. G.
Published: August 2009

A neurokinin (NK‐1) receptor antagonist, [14C]Aprepitant, was synthesized using two labeled olefination reagents: [14C]dimethyltitanocene 1 and [14C]methyl (methyltrimethylsilyl)titanocene 7. Both reagents can be readily prepared from [14C]methyllithium and have been shown to convert a variety of carbonyls to [14C]methylenes in good radiochemical yields. Copyright © 2009 John Wiley & Sons, Ltd.
Factors affecting the next generation of women leaders: Mapping the challenges, antecedents, and consequences of effective leadership
Authors: McEldowney Rene P. , Bobrowski Paula , Gramberg Anna
Published: August 2009

This article introduces a conceptual model for understanding how young women perceive the current challenges of leadership. Numerous studies and articles claim that women are better educated, more experienced, and better suited for leadership positions than ever before. This news is encouraging, but the number of women in leadership roles in American politics gained less than one percentage point this year, hovering around 22%, while in the private sector many organizations have yet to place a single woman on their board. The proportion of women on corporate boards is 16%, with no evidence that this is likely to grow in the near future. What is even more discouraging is that these low numbers are not significantly higher than those in many developing nations. It is evident that women are underrepresented in top leadership positions and must intensely challenge the status quo. This article presents results of a study based on in‐depth interviews with college women who are seeking paths to leadership. The researchers employ qualitative analytical research tools to explore the complexities of the phenomena. The findings bring a greater understanding of the antecedents and consequences that lie beneath the challenges affecting the next generation of women leaders.
An empirical study of other‐oriented and rational self‐interest leadership approaches
Authors: Barrow Lisa M. S. , Mirabella Jim
Published: August 2009

Other orientation is defined as “the extent to which individuals are concerned with the welfare of others” (Meglino & Korsgaard, 2007, p. 59). Other‐oriented leaders focus their attention on organizational objectives coupled with a human resource emphasis, whereas rational self‐interested leaders concern themselves with organizational objectives coupled with self‐emphasis. This quantitative study examines philanthropian and servant leadership, which are other‐oriented leadership approaches, and transactional leadership, which is a rational self‐interested leadership approach, to determine the effectiveness of the approaches in the 21st century. This study further examines the results of a hermeneutic phenomenological study of philanthropian leadership that introduced a new other‐oriented leadership model. This study focuses on leadership preferences of leaders, employees, and third‐year undergraduate business students to determine if there is a significant difference between preferences among groups for other‐oriented and rational self‐interest‐oriented leadership approaches.
Experience matters in principal preparation
Authors: Nelson Sarah W.
Published: August 2009

An act of leadership is always an act of practical theory. We lead because we hold visions of the world as it ought to be, because of the not yet, because of the potential that we see in ideas and people. Yet, there still exists a perceived binary between leadership theory (in the strong sense) and leadership practice, a binary that divides organizations, classrooms, and the differing bodies of leadership literature. In this Symposium, Duncan Waite and his colleagues discuss the barriers they have faced in bringing theory to the educational leadership classroom, as well as the promise they feel theory holds for more productive, equitable, and humane schooling organizations.
A response to LDR 2 LDR: Theory and practice working together
Authors: Henry Genise
Published: August 2009

An act of leadership is always an act of practical theory. We lead because we hold visions of the world as it ought to be, because of the not yet, because of the potential that we see in ideas and people. Yet, there still exists a perceived binary between leadership theory (in the strong sense) and leadership practice, a binary that divides organizations, classrooms, and the differing bodies of leadership literature. In this Symposium, Duncan Waite and his colleagues discuss the barriers they have faced in bringing theory to the educational leadership classroom, as well as the promise they feel theory holds for more productive, equitable, and humane schooling organizations.
A response to LDR 2 LDR: KNEX 2 U
Authors: Holcomb Michelle R.
Published: August 2009

An act of leadership is always an act of practical theory. We lead because we hold visions of the world as it ought to be, because of the not yet, because of the potential that we see in ideas and people. Yet, there still exists a perceived binary between leadership theory (in the strong sense) and leadership practice, a binary that divides organizations, classrooms, and the differing bodies of leadership literature. In this Symposium, Duncan Waite and his colleagues discuss the barriers they have faced in bringing theory to the educational leadership classroom, as well as the promise they feel theory holds for more productive, equitable, and humane schooling organizations.
The memory of practice and the mirror of theory
Authors: Jenlink Patrick M.
Published: August 2009

An act of leadership is always an act of practical theory. We lead because we hold visions of the world as it ought to be, because of the not yet, because of the potential that we see in ideas and people. Yet, there still exists a perceived binary between leadership theory (in the strong sense) and leadership practice, a binary that divides organizations, classrooms, and the differing bodies of leadership literature. In this Symposium, Duncan Waite and his colleagues discuss the barriers they have faced in bringing theory to the educational leadership classroom, as well as the promise they feel theory holds for more productive, equitable, and humane schooling organizations.
Palaeoglaciation of Bayan Har Shan, northeastern Tibetan Plateau: glacial geology indicates maximum extents limited to ice cap and ice field scales
Authors: Heyman Jakob , Stroeven Arjen P. , Alexanderson Helena , Hättestrand Clas , Harbor Jon , Li Yingkui , Caffee Marc W. , Zhou Liping , Veres Daniel , Liu Feng , Machiedo Martin
Published: August 2009

Key locations within an extensive area of the northeastern Tibetan Plateau, centred on Bayan Har Shan, have been mapped to distinguish glacial from non‐glacial deposits. Prior work suggests palaeo‐glaciers ranging from valley glaciers and local ice caps in the highest mountains to a regional or even plateau‐scale ice sheet. New field data show that glacial deposits are abundant in high mountain areas in association with large‐scale glacial landforms. In addition, glacial deposits are present in several locations outside areas with distinct glacial erosional landforms, indicating that the most extensive palaeo‐glaciers had little geomorphological impact on the landscape towards their margins. The glacial geological record does indicate extensive maximum glaciation, with local ice caps covering entire elevated mountain areas. However, absence of glacial traces in intervening lower‐lying plateau areas suggests that local ice caps did not merge to form a regional ice sheet on the northeastern Tibetan Plateau around Bayan Har Shan. No evidence exists for past ice sheet glaciation. Copyright © 2009 John Wiley & Sons, Ltd.
Vibrational spectroscopic studies, conformations and ab initio calculations of 1,2‐bis(trifluorosilyl)ethane (SiF3CH2CH2SiF3)
Authors: Klaeboe Peter , Nielsen Claus J. , Horn Anne , Guirgis Gamil A. , Kilway Kathleen V.
Published: August 2009

Infrared spectra of 1,2‐bis(trifluorosilyl)ethane (SiF3CH2CH2SiF3) were obtained in the vapour and liquid phases, in argon matrices and in the solid phase. Raman spectra of the compound as a liquid were recorded at various temperatures between 293 and 270 K and spectra of an apparently crystalline solid were observed. The spectra revealed the existence of two conformers (anti and gauche) in the vapour, liquid and in the matrix. When the vapour was chock‐frozen on a cold finger at 78 K and annealed to 150 K, certain weak Raman bands vanished in the crystal. The vibrational spectra of the crystal demonstrated mutual exclusion between IR and Raman bands in accordance with C2h symmetry. Intensity variations between 293 and 270 K of pairs of various Raman bands gave ΔH(gauche—anti) = 5.6 ± 0.5 kJ mol−1 in the liquid, suggesting 85% anti and 15% gauche in equilibrium at room temperature. Annealing experiments indicate that the anti conformer also has a lower energy in the argon matrices, is the low‐energy conformer in the liquid and is also present in the crystal. The spectra of both conformers have been interpreted, and 34 anti and 17 gauche bands were tentatively identified. Ab initio and density functional theory (DFT) calculations were performed giving optimized geometries, infrared and Raman intensities and anharmonic vibrational frequencies for both conformers. The conformational energy difference derived in CBS‐QB3 and in G3 calculations was 5 kJ mol−1. Copyright © 2009 John Wiley & Sons, Ltd.
A comparative LSER study of the reactivity of 2‐substituted cyclohex‐1‐eneacetic and 2‐substituted phenylacetic acids with diazodiphenylmethane in various solvents
Authors: Nikolić J. B. , Ušćumlić G. S. , Juranić Ivan O.
Published: August 2009

The rate constants for the reaction of 2‐substituted cyclohex‐1‐eneacetic and 2‐substituted phenylacetic acids with diazodiphenylmethane were determined in various aprotic solvents at 30°C. To explain the kinetic results through solvent effects, the second‐order rate constants of the examined acids were correlated using the Kamlet–Taft solvatochromic equation. The correlations of the kinetic data were carried out by means of multiple linear regression analysis, and the solvent effects on the reaction rates were analyzed in terms of initial and transition state contributions. The opposite signs of the electrophilic and the nucleophilic parameters are in agreement with the well‐known mechanism of the reaction of carboxylic acids with diazodiphenylmethane. The quantitative relationship between the molecular structure and the chemical reactivity is discussed, as well as the effect of the molecular geometry on the reactivity of the examined compounds. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 613–622, 2009
β‐Ionone reactions with the nitrate radical: Rate constant and gas‐phase products
Authors: Harrison Joel C. , Ham Jason E.
Published: August 2009

The bimolecular rate constant of k (9.4 ± 2.4 × 10−12 cm3 molecule−1 s−1 was measured using the relative rate technique for the reaction of the nitrate radical (NO3•) with 4‐(2,6,6‐trimethyl‐1‐cyclohexen‐1‐yl)‐3‐buten‐2‐one (β‐ionone) at (297 ± 3) K and 1 atmosphere total pressure. In addition, the products of β‐ionone + NO3• reaction were also investigated. The identified reaction products were glyoxal (HC(O)C(O)H), and methylglyoxal (CH3C(O)C(O)H). Derivatizing agents O‐(2,3,4,5,6‐pentafluorobenzyl)hydroxylamine and N,O‐bis(trimethylsilyl)trifluoroacetamide were used to propose the other major reaction products: 3‐oxobutane‐1,2‐diyl nitrate, 2,6,6‐trimethylcyclohex‐1‐ene‐carbaldehyde, 2‐oxo‐1‐(2,6,6‐trimethylcyclohex‐1‐en‐1‐yl)ethyl nitrate, pentane‐2,4‐dione, 3‐oxo‐1‐(2,6,6‐trimethylcyclohex‐1‐en‐1‐yl)butane‐1,2‐diyl dinitrate, 3,3‐dimethylcyclohexane‐1,2‐dione, and 4‐oxopent‐2‐enal. The elucidation of these products was facilitated by mass spectrometry of the derivatized reaction products coupled with plausible β‐ionone + NO3• reaction mechanisms based on previously published volatile organic compound + NO3• gas‐phase mechanisms. The additional gas‐phase products 5‐acetyl‐2‐ethylidene‐3‐methylcyclopentyl nitrate, 1‐(1‐hydroxy‐7,7‐dimethyl‐2,3,4,5,6,7‐hexahydro‐1 H‐inden‐2‐yl)ethanone, 1‐(1‐hydroxy‐3a,7‐dimethyl‐2,3,3a,4,5,6,‐hexahydro‐1 H‐inden‐2‐yl)ethanone, and 5‐acetyl‐2‐ethylidene‐3‐methylcyclopentanone are proposed to be the result of cyclization through a reaction intermediate. © 2009 Wiley Periodicals, Inc.*

This article is a U.S. Government work and, as such, is in the public domain of the United States of America.

Int J Chem Kinet 41: 629–641, 2009
effect of initial reagent concentrations on the oscillatory behavior of the BZ reaction in a batch reactor
Authors: Ganaie Nadeem B. , Peerzada G. M.
Published: August 2009

A detailed investigation on resorcinol as the Belousov–Zhabotinsky (BZ) oscillator in manganese(II) ion catalyzed reaction system with inorganic bromate (oxidant) and acetone (cosubstrate) was carried out in aqueous sulfuric acid medium (1.3 M). The aforesaid reagents were mixed with various concentrations to evolve the effective concentrations at which the reaction system exhibited better oscillations. The various oscillatory parameters such as time period (tp), induction period (tin), frequency (v), amplitude (A), and number of oscillations (n) were derived, and the dependence of concentration of the reacting species on these oscillatory parameters was interpreted on the basis of the Field–Koros–Noyes mechanism. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 650–657, 2009
Study of the electron transfer reaction between [Co(EDTA)]− and [Ru(NH3)5py]2+ in methanol–water mixtures
Authors: Villa I. , Sanchez F. , Perez‐Tejeda P.
Published: August 2009

The title reaction was studied in different water–cosolvent (methanol) mixtures. The results have been rationalized employing the Marcus–Hush treatment. To apply this treatment, the true, unimolecular, electron‐transfer rate constants (ket) were obtained from the experimentally measured rate constants after calculation of the equilibrium constant for the processes of formation of the encounter complex. This calculation was carried out using Eigen–Fuoss (EF) and exponential mean spherical (EMSA) approaches employing effective values of the solvent dielectric constant. These effective values were obtained from the measured association constants corresponding to other ion pairs. The results reveal that in these media there is an additional component of reorganization energy, absent in neat solvents. An explanation of the origin of this component is given. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 658–666, 2009
Corrosion behavior of Mg‐10Gd‐2Y‐0.4Zr alloy under thin electrolyte layers
Authors: Chen C. , Zhang T. , Meng G. , Shao Y. , Wang F. , Li X. , Dong C.
Published: August 2009

The corrosion behavior of Mg‐10Gd‐2Y‐0.4Zr (GW102K) alloy under thin electrolyte layer (TEL) with various thicknesses was investigated by means of cathodic polarization curve, electrochemical impedance spectroscopy (EIS), and electrochemical noise (EN). Based on shot noise theory and stochastic theory, the EN results were quantitatively analyzed by using the Weibull and Gumbel distribution function, respectively. The experimental results showed that the anodic and cathodic processes of the corrosion of GW102K alloy were both retained under thin electrolyte layers. Whether under TEL or not, the cathodic process was dominated by hydrogen evolution reaction. The corrosion was more localized under thin electrolyte layer than that in bulk solution. The results also demonstrated that there were two kinds of effects for thin electrolyte layer on the corrosion behavior of GW102K alloy: (i) the rate of pit initiation was evidently retarded compared to that in bulk solution; (ii) the probability of pit growth decreased, which should be the real reason why the corrosion rate of GW102K alloy decreased with the decrease in layer thickness.
Influence of ball‐milling on the oxidation behavior of Ag–Zn alloy powders
Authors: Yi D. Q. , Wu C. P. , Goto S. , Xu C. H. , Li J. , Wang B. , Xiao L. R. , Zheng F.
Published: August 2009

The gas atomized Ag–15.2 at% Zn alloy powders were treated using ball‐milling. The effect of ball‐milling on surface morphology, microstructure, and oxidation behavior of the alloy powders was investigated. The results showed that ball‐milling treatment enhanced the oxidation rate of Ag–Zn alloy powders due to the increase of dislocation density and the decrease of the diffusion distance of oxygen during internal oxidation. The fully oxidized time of Ag–Zn alloy powders decreases with the ball‐milling time. In addition, the ball‐milling treatment not only changes the oxidation mechanism but also improves microstructure and properties of the Ag–ZnO materials fabricated by internal oxidation.
Electrochemical and SEM studies of a new implant bioalloy in physiological electrolytes
Authors: Popa M. V. , Vasilescu E. , Drob P. , Mareci D. , Moreno J. M. Calderon , Ivanescu S. , Vasilescu C. , Rosca J. C. Mirza
Published: August 2009

A new implant Ti–7Al–3V–2Mo–2Fe alloy was elaborated and its behaviour in Ringer–Brown and Ringer solutions (of different pH values) was studied using cyclic potentiodynamic and linear polarisation, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) with its link energy dispersive X‐ray system (EDX). Cyclic potentiodynamic polarisation curves revealed that the Ti–7Al–3V–2Mo–2Fe alloy is self‐passivated in Ringer solutions. Pitting corrosion appeared in alkaline Ringer solution but at very electropositive values of the breakdown and pitting protection potentials and it is not possible to develop local corrosion on this alloy, even in extreme functional conditions. EIS spectra at open circuit potential exhibited two phase angles characterising a resistant passive film and some charge transfer reactions. SEM–EDX analysis shows the presence of some aggregates containing complex compounds of calcium, magnesium, phosphor, silicon deposited on the alloy surface.
On the applicability of high strength self‐tapping aluminium bolts in magnesium nut materials for automotive applications
Authors: Gerstmayr G. , Mori G. , Leitner H. , Eichlseder W.
Published: August 2009

High strength aluminium bolts made of AW 6056 T6, AW 7075 T6 and T79 have been investigated regarding the applicability in magnesium nut materials for automotive applications. With respect to galvanic corrosion all combinations of aluminium bolts with magnesium parts show superior corrosion properties when compared to galvanised steel bolts connected to magnesium. With respect to stress corrosion cracking (SCC) no aluminium bolt in contact with magnesium failed due to SCC. This is because of cathodic protection of aluminium alloy through magnesium. Even peak‐tempered highest strengthened T6 7xxx aluminium bolts can be used for automotive applications when compressive residual stresses are present in the thread root of the bolts.
Atom Transfer Radical Polymerization (ATRP) of Methyl Methacrylate using a Functional Initiator Bearing an Amino‐Adamantane
Authors: Kavitha Amalin A. , Singha Nikhil K.
Published: August 2009

This investigation reports the preparation of poly(methyl methacrylate)s bearing amino adamantyl functionality as the end‐group via atom transfer radical polymerization (ATRP) using amino‐adamantyl isobutyryl bromide (Am‐AdiBr) as initiator. The rate of polymerization was slow compared to that of ATRP of methyl methacrylate (MMA) using conventional ATRP initiator. This may be due to the coordination between amine group and copper catalyst. All the polymers had well‐defined end group. The presence of end group was confirmed by 1H NMR, MALDI‐TOF‐MS analysis, and block copolymerization experiments using PMMA bearing –Br end group as the macroinitiator. The thermal properties of the polymer were investigated by TGA and DSC analysis.

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The analysis of dioxins and related compounds
Authors: Reiner Eric J.
Published: August 2009

The analysis of polychlorinated dibenzo‐p‐dioxins, polychlorinated dibenzofurans, polychlorinated biphenyls, and other related compounds requires complex sample preparation and analytical procedures using highly sensitive and selective state‐of‐the‐art instrumentation to meet very stringent data quality objectives. The analytical procedures (extraction, sample preparation), instrumentation (chromatographic separation and detection by mass spectrometry) and screening techniques for the determination of dioxins, furans, dioxin‐like polychlorinated biphenyls and related compounds with a focus on new approaches and alternate techniques to standard regulatory methods are reviewed. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:526–559, 2010
Clinical and genetic characteristics of Mexican Huntington's disease patients
Authors: Alonso María Elisa , Ochoa Adriana , Boll Marie‐Catherine , Sosa Ana Luisa , Yescas Petra , López Marisol , Macias Rosario , Familiar Itziar , Rasmussen Astrid
Published: August 2009

We report the characteristics of 691 Mexican patients with Huntington's disease (HD). These patients, representing 401 families, constitute the largest series of Mexican HD cases as yet described in the literature. We found the clinical characteristics of these patients to be similar to those of other populations, but we observed a higher frequency of infantile cases, a shorter disease duration and a lower suicide rate. In 626 cases, for which molecular analyses were available, CAG‐trinucleotide expansion size ranged from 37–106 repeats. The large number of CAG repeats (19.04 ± 3.02) in normal alleles and the presence of new mutations suggest that the overall prevalence of HD in the Mexican population could be expected to be within range of, or higher than, that reported for Europeans. © 2009 Movement Disorder Society
Quantitative lateralized measures of bradykinesia at different stages of Parkinson's disease: The role of the less affected side
Authors: Louie Stephanie , Koop Mandy Miller , Frenklach Anna , Bronte‐Stewart Helen
Published: August 2009

The onset of motor abnormalities in Parkinson's disease (PD) is usually unilateral. However, current therapeutic trials do not analyze separately the performance of the more affected (MA) and less affected (LA) limbs. From a cohort of 85 subjects at different stages of PD, we asked whether the relationship between bradykinesia and disease severity was similar on both limbs and if the MA side remained more bradykinetic than the LA side in advanced PD. MA and LA limb determination was made from the history of the side first affected. Twenty‐one age‐matched subjects were used as controls. The velocities of finger and arm movements on both sides were inversely correlated with disease severity (P < 0.03). The slope of the decline in wrist movement velocity was steeper on the LA side (P = 0.029). When the regression lines were extrapolated to the y‐axis (UPDRS III = 0) the performance of the LA side was not different from that of controls (P = 0.954 and P = 0.829 for finger and arm movements, respectively), whereas that of the MA side was slower (P = 0.019 and P = 0.016), suggesting that at the theoretical state of no disease the LA side would reflect less or no contralateral nigral pathology. With increasing disease severity, there was less difference between MA and LA sides in both finger and arm bradykinesia (P < 0.004). These findings highlight the value of analyzing separately the MA and LA sides in subjects with PD, especially for clinical trials of potential disease modifying agents in early stages of disease. © 2009 Movement Disorder Society
A necessary and sufficient condition for a Bedrosian identity
Authors: Cerejeiras P. , Chen Q. , Kähler U.
Published: August 2009

We present a sufficient and necessary condition for the Bedrosian identity to hold for a large class of mono‐components based on a generalized Sinc‐function. Copyright © 2009 John Wiley & Sons, Ltd.
Quantifying oxygen diffusion in paraffin oil used in oocyte and embryo culture
Authors: Stokes Yvonne M.
Published: August 2009

Oxygen diffusion through oil is important in the culture of oocytes and embryos. A diffusion coefficient two orders of magnitude smaller than that of oxygen in water has been thought possible, and this has led to concerns of anoxia in cultures. Using an assay for determining the oxygen consumption rate of embryos and oocytes, along with a mathematical model, it is here shown that the oxygen diffusion rate in paraffin oil at 37°C is about two‐thirds of that in water at the same temperature. Although not previously recognised for the assay in question, the geometry is such that anoxia does occur for a period of time in excess of 1 hr and, by the completion of the assay, 30–40% of the medium is anoxic. Hence the quantity of oxygen consumed is less than would be consumed in conditions of plentiful oxygen supply. Nevertheless, using a model with a concentration dependent oxygen consumption rate, the oxygen consumption rate can be estimated. Mol. Reprod. Dev. 76: 1178–1187, 2009. © 2009 Wiley‐Liss, Inc.
Four‐dimensional (4D) flow of the whole heart and great vessels using real‐time respiratory self‐gating
Authors: Uribe Sergio , Beerbaum Philipp , Sørensen Thomas Sangild , Rasmusson Allan , Razavi Reza , Schaeffter Tobias
Published: August 2009

Four‐dimensional (4D) flow imaging has been used to study flow patterns and pathophysiology, usually focused on specific thoracic vessels and cardiac chambers. Whole‐heart 4D flow at high measurement accuracy covering the entire thoracic cardiovascular system would be desirable to simplify and improve hemodynamic assessment. This has been a challenge because compensation of respiratory motion is difficult to achieve, but it is paramount to limit artifacts and improve accuracy. In this work we propose a self‐gating technique for respiratory motion‐compensation integrated into a whole‐heart 4D flow acquisition that overcomes these challenges. Flow components are measured in all three directions for each pixel over the complete cardiac cycle, and 1D volume projections are obtained at certain time intervals for respiratory gating in real time during the acquisition. The technique was tested in 15 volunteers, in which stroke volumes (SVs) in the great arteries showed excellent agreement with standard 2D phase‐contrast (PC) scans. In contrast, nongated 4D flow with two averages had substantial disagreement with 2D flow. Applied to patients with congenital cardiac left‐to‐right shunting, the precision of flux data was highly beneficial. The methodology presented here has the potential to allow a complete study of flow pathophysiology of the thoracic cardiovascular system from a single free‐breathing scan. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Increased expression and cellular localization of lipocalin‐type prostaglandin D synthase in Helicobacter pylori‐induced gastritis
Authors: Hokari Ryota , Nagata Nanae , Kurihara Chie , Watanabe Chikako , Komoto Shunsuke , Okada Yoshikiyo , Kawaguchi Atsushi , Nagao Shigeaki , Hibi Toshifumi , Nagata Kinya , Urade Yoshihiro , Miura Soichiro
Published: August 2009

Immunological responses in the host can result in different disease outcomes of Helicobacter pylori‐induced gastritis. Prostaglandin E2 derived from cyclooxygenase (COX) and prostaglandin E synthase contribute to gastric protection. Recently, prostaglandin D2 was shown to be involved in host immunity by chemotactic activity through chemoattractant receptor‐homologous molecule expressed on Th2 cells (CRTH2), but its role in H. pylori‐induced gastritis has not been clarified. We determined the expression levels of mRNAs for haematopoietic PGD synthase (H‐PGDS) and lipocalin‐type PGDS (L‐PGDS), MIP‐1 alpha, IFN‐gamma, IL‐4, and CDX2 in H. pylori‐induced gastritis mucosa by quantitative RT‐PCR. We found that L‐PGDS was constitutively expressed in the epithelium of the glandular base. L‐PGDS, but not H‐PGDS, was induced on fibroblasts close to infiltrating cells in the H. pylori‐infected gastric mucosa. These fibroblasts co‐expressed COX‐2. The level of L‐PGDS mRNA expression decreased as gastritis became more severe. In most of the H. pylori‐infected gastric mucosa, CCR5(+) cells had more actively infiltrated than had CRTH2(+) cells. However, the expression level of IFN‐gamma was lower in the mucosa of the CRTH2(+) cells‐dominantly infiltrating group than that of the less CRTH2‐infiltrating group. Exogenously added PGD2 decreased the H. pylori‐induced expression of IFN‐gamma in peripheral blood mononuclear cells in vitro. The data suggest that PGD2 derived from the gastric mucosa and fibroblasts plays protective roles against inflammatory changes in H. pylori‐induced gastritis. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Cytogenetic characterization of childhood acute lymphoblastic leukemia in Nicaragua
Authors: Ceppi Francesco , Brown Angela , Betts David R. , Niggli Felix , Popovic Maja Beck
Published: August 2009

Background

Within the frame of a twinning programme with Nicaragua, The La Mascota project, we evaluated in our study the contribution of cytogenetic characterization of acute lymphoblastic leukemia (ALL) as prognostic factor compared to clinical, morphological, and immunohistochemical parameters.

Methods

All patients with ALL treated at the only cancer pediatric hospital in Nicaragua during 2006 were studied prospectively. Diagnostic immunophenotyping was performed locally and bone marrow or blood samples were sent to the cytogenetic laboratory of Zurich for fluorescence in situ hybridization (FISH) analysis and G‐banding.

Results

Sixty‐six patients with ALL were evaluated. Their mean age at diagnosis was 7.3 years, 31.8% were ≥10 years. Thirty‐four patients (51.5%) presented with hyperleucocytosis ≥50 × 109/L, 45 (68.2%) had hepatosplenomegaly. Immunophenotypically 63/66 patients (95%) had a B‐precursor, 2 (3%) a T‐ and 1 (1.5%) a B‐mature ALL. FISH analysis demonstrated a TEL/AML1 fusion in 9/66 (14%), BCR/ABL fusion in 1 (1.5%), MLL rearrangement in 2 (3.1%), iAMP21 in 2 (3.1%), MYC rearrangement in 1 (1.5%), and high‐hyperdiploidy in 16 (24%). All patients but two with TEL/AML1 fusion and high‐hyperdiploidy were clinically and hematologically in the standard risk group whereas those with poor cytogenetic factors had clinical high‐risk features and were treated intensively.

Conclusions

Compared to Europe, the ALL population in Nicaragua is older, has a higher proportion of poor prognostic clinical and hematological features and receives more intensive treatment, while patients with TEL/AML1 translocations and high‐hyperdiploidy are clinically in the standard risk group. Cytogenetics did not contribute as an additional prognostic factor in this setting. Pediatr Blood Cancer 2009; 53:1238–1241. © 2009 Wiley‐Liss, Inc.
Erwinia asparaginase after allergy to E. coli asparaginase in children with acute lymphoblastic leukemia
Authors: Vrooman Lynda M. , Supko Jeffrey G. , Neuberg Donna S. , Asselin Barbara L. , Athale Uma H. , Clavell Luis , Kelly Kara M. , Laverdière Caroline , Michon Bruno , Schorin Marshall , Cohen Harvey J. , Sallan Stephen E. , Silverman Lewis B.
Published: August 2009

Background

Escherichia coli asparaginase is an important component of treatment for childhood acute lymphoblastic leukemia (ALL); however, hypersensitivity develops in up to 30% of patients. We assessed the nadir enzyme activity and tolerability of Erwinia asparaginase, an alternative preparation, in E. coli asparaginase‐allergic patients.

Patients and Methods

Between 2000 and 2002, 215 children with newly diagnosed ALL were enrolled on Dana‐Farber Cancer Institute ALL Consortium Protocol 00‐01 and were to receive 30 weekly doses of intramuscular E. coli asparaginase. If E. coli asparaginase allergy developed, patients were switched to twice‐weekly intramuscular Erwinia asparaginase (25,000 IU/m2). Nadir serum asparaginase activity (NSAA) was measured every 3 weeks.

Results

Forty‐two patients (20%) developed E. coli asparaginase allergy and switched to Erwinia. Of 38 patients with evaluable samples, 34 (89%) Erwinia‐treated patients had at least one therapeutic NSAA (≥0.1 IU/ml). The median NSAA was 0.247 IU/ml 3 days and 0.077 IU/ml 4 days after an Erwinia dose. Associated toxicities included allergy in 14 (33%) and pancreatitis in 3 patients (7%). At a median follow‐up of 5.4 years, event‐free survival (±standard error) of the 42 patients who switched to Erwinia was 86 ± 5% compared with 81 ± 3% for the 170 patients without E. coli asparaginase allergy (P = 0.55).

Conclusions

Twice‐weekly Erwinia asparaginase was well tolerated and achieved a therapeutically effective NSAA in most E. coli asparaginase‐allergic patients. Development of E. coli allergy and subsequent treatment with twice‐weekly Erwinia did not adversely impact event‐free survival. Erwinia asparaginase should be considered for E. coli asparaginase‐allergic patients. Pediatr Blood Cancer 2010;54:199–205. © 2009 Wiley‐Liss, Inc.
Tensile properties and reinforcement mechanisms of natural rubber/vapor‐grown carbon nanofiber composite
Authors: Jiang Hong‐Xia , Ni Qing‐Qing , Natsuki Toshiaki
Published: August 2009

Natural rubber (NR) composites with different contents of 1, 3, 10, and 20 wt% vapor‐grown carbon nanofibers (VGCFs) were synthesized using a solvent casting method. The initial modulus of composites was improved by 26.5 %/wt% as the VGCFs were added, and the NR/3 wt%VGCF composite had the largest tensile strength. The experiment values of initial moduli agreed well with the values predicted by the Halpin‐Tsai theory. The reinforcement mechanisms of the composites were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and wide‐angle X‐ray diffraction (WAXD). It was found that an efficient stress transfer occurred from NR to VGCFs under the uniaxial stretching. The addition of 10 wt% VGCFs could promote the nucleation process of NR, which resulted in the characteristic of the strain‐induced crystallization (SIC) in NR/10 wt%VGCF composite even for low strain. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Feasibility and usefulness of the ‘Distress Screening Program in Ambulatory Care’ in clinical oncology practice
Authors: Shimizu Ken , Ishibashi Yuki , Umezawa Shino , Izumi Hideko , Akizuki Nobuya , Ogawa Asao , Fujiwara Yasuhiro , Ando Masashi , Katsumata Noriyuki , Tamura Kenji , Kouno Tsutomu , Shimizu Chikako , Yonemori Kan , Yunokawa Mayu , Uchitomi Yosuke
Published: August 2009

Objective: Although the implementation of routine screening for distress is desirable, doing so is difficult in today's busy clinical oncology practice. We developed the ‘Distress Screening Program in Ambulatory Care’ (DISPAC program) as a practical means of screening for and facilitating the treatment of major depression and adjustment disorders in cancer patients. This study assessed the feasibility and usefulness of the DISPAC program in actual clinical situations.

Methods: As part of the DISPAC program, nurses administered a psychological screening measure, the Distress and Impact Thermometer (DIT), to consecutive cancer patients visiting an outpatient clinic in the waiting room. The attending physician then recommended psycho‐oncology service referral to all positively screened patients. We compared the proportion of patients referred to a psycho‐oncology service during the DISPAC period with the usual care period.

Results: Of the targeted 491 patients treated during the DISPAC period, 91.9% (451/491) completed the DIT; the results were positive in 37.0% (167/451), recommendations for referrals were given to 93.4% (156/167), and 25.0% (39/156) accepted the referral. Ultimately 5.3% (26/491) of the targeted patients were treated by psycho‐oncology service as having major depression or adjustment disorders, a significantly higher proportion than during the usual care period (0.3%; p<0.001). The nurses required 132±58 s per person to administer the DIT.

Conclusions: The DISPAC program is useful for facilitating the care of cancer patients with psychological distress. Nevertheless, the acceptance of referrals by patients and the reduction of the burden placed on nurses are areas requiring improvement. Copyright © 2009 John Wiley & Sons, Ltd.
Nocturnal cough in children with stable cystic fibrosis
Authors: van der Giessen Lianne , Loeve Martine , de Jongste Johan , Hop Wim , Tiddens Harm
Published: August 2009

Introduction

To date no studies have been published on nocturnal cough frequency in children with stable CF. Aim of the study was to assess nocturnal cough frequency in children with CF. In addition nocturnal cough frequency was correlated with parameters of disease severity.

Methods

During two nights cough was recorded with a digital audio recorder in 25 patients (mean age 13 years; range 6–19) with clinically stable CF. In addition oxygen saturation was measured. The day following the recording spirometry was carried out. CT scores were obtained from the most recent routine CT scan. Cough was expressed in cough seconds (csec) and in cough seconds per hour (csec/hr).

Results

Data shown are median values and interquartile range (IQR). First night: 8 csec (IQR 3–52); 0.9 csec/hr (IQR 0.3–6.1) Second night: 6 csec (IQR 2–32); 0.6 csec/hr (IQR 0.1–3.4). Csec in the 1st night did not correlate significantly with csec in the 2nd night. Only for the 2nd night a strong correlation was found between csec/hr and the FEV1%pred (rs = −0.75, P < 0.001) and FEF75 %pred (rs = −0.71, P < 0.001). Bronchiectasis score correlated borderline with the mean csec/hr of both nights (rs = 0.39, P = 0.08). During both nights cough was significantly higher in the first hour of sleep (P ≤ 0.04).

Conclusion

Frequency of nocturnal coughing in children with CF was higher than that described for normal children. Nocturnal cough tended to be more severe in children with more advanced CF lung disease. Nocturnal cough was more severe in the first hour of sleep and varied from night‐to‐night. Pediatr Pulmonol. 2009; 44:859–865. © 2009 Wiley‐Liss, Inc.