bluuebunny/crossref_metadata_2025 huggingface dataset:
Septal rupture: Effect of oxygen administration
Authors: Hollander G. , Horowitz J. , Greengart A. , Shani J. , Lichstein E.
Published: February 2009

A patient with interventricular septal rupture as a complication of myocardial infarction was studied to determine whether varying the concentration of inspired oxygen would alter the magnitude of intracardiac shunt. A significant correlation was found showing that high concentration of inspired oxygen results in increased left to right shunting probably due to systemic vasoconstriction and pulmonary vasodilatation.
Unusual electrocardiogram in hypertrophic cardiomyopathy
Authors: Teplitsky I. , Wurzel M. , Aygen M.
Published: February 2009

Electrocardiographic criteria of right ventricular hypertrophy were found in a 17‐year‐old male with nonobstructive hypertrophic cardiomyopathy involving the left ventricle. Right ventricular hypertrophy pattern is a rare electrocardiographic abnormality in patients with hypertrophic cardiomyopathy and the presence of Q waves in leads V5‐V6 could be helpful in differentiating this syndrome from true right ventricular hypertrophy.
The 4G/5G promotor polymorphism of the plasminogen activator inhibitor‐1 gene and late lumen loss after coronary stent placement in smoking and nonsmoking patients
Authors: Ortlepp Jan R. , Hoffmann Rainer , Killian Astrid , Lauscher Johannes , Merkelbach‐Bruse Sabine , Hanrath Peter
Published: February 2009

Background: Instent restenosis remains a significant clinical problem. Identification of patients at risk for instent restenosis may allow selection of individualized appropriate therapeutic approaches. Genetic polymorphisms have been suggested to be associated with the risk of instent restenosis. Smoking is known to influence hemostatic parameters.

Hypothesis: This study investigated the influence of the 4G/5G promotor polymorphism of the plasminogen activator inhibitor type 1 (PAI‐1) gene on instent restenosis in smoking and nonsmoking patients.

Methods: in all, 300 consecutive patients (133 nonsmoking; 167 smoking) with elective coronary stent placement and 6‐month angiographic follow‐up were studied. Quantitative coronary angiography and genotyping with polymerase chain reaction analysis were performed in all patients.

Results: Nonsmoking PAI‐1 4G/4G carriers showed a significantly greater late lumen loss (n = 38; 0.54 ± 0.53 mm) compared with nonsmoking PAI‐14G/5G (n = 68; 0.38 ± 0.45 mm) or 5G/5G (n = 27; 0.19 ± 0.23 mm) carriers, analysis of variance (ANOVA) p<0.001. Smoking patients with the genotypes 4G/4G (n = 46; 0.53 ± 0.54 mm) and 4G/5G (n = 79; 0.37 ± 0.41 mm) had a late loss similar to that of nonsmoking patients. Smoking 5G/5G carriers had the highest late loss of all smoking patients (n = 42; 0.63 ± 0.50); ANOVA p < 0.05; nonsmoking 5G/5G vs. smoking 5G/5G p < 0.001.

Conclusion: The promotor polymorphism of the PAI‐1 gene has a significant influence on instent restenosis after coronary stent implantation. The 5G/5G genotype predisposes nonsmoking gene carriers to less late lumen loss, whereas in smoking gene carriers this genotype is associated with the greatest late lumen loss. This might be explained by an altered expression pattern of hemostatic parameters.
Cover Picture: Structure–Activity Relationship Analysis of the Peptide Deformylase Inhibitor 5‐Bromo‐1H‐indole‐3‐acetohydroxamic Acid (ChemMedChem 2/2009)
Authors: Petit Sylvain , Duroc Yann , Larue Valéry , Giglione Carmela , Léon Carole , Soulama Coralie , Denis Alexis , Dardel Frédéric , Meinnel Thierry , Artaud Isabelle
Published: February 2009

The cover picture shows a “reverse” indole derivative in complex with Bacillus stearothermophilus peptide deformylase (PDF). This compound was selected from a structure–activity relationship study as a potent inhibitor of bacterial PDFs and shows antibacterial activity toward Bacillus subtilis as well as other pathogens such as Streptococcus pneumoniae and Staphylococcus aureus. For more details, see the Full Paper by I. Artaud et al. on p. 261 ff.

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Osteosarcoma incidence and survival rates from 1973 to 2004
Authors: Mirabello Lisa , Troisi Rebecca J. , Savage Sharon A.
Published: February 2009

BACKGROUND:

Osteosarcoma, which is the most common primary bone tumor, occurs most frequently in adolescents, but there is a second incidence peak among individuals aged >60 years. Most osteosarcoma epidemiology studies have been embedded in large analyses of all bone tumors or focused on cases occurring in adolescence. Detailed descriptions of osteosarcoma incidence and survival with direct comparisons among patients of all ages and ethnicities are not available.

METHODS:

Frequency, incidence, and survival rates for 3482 patients with osteosarcoma from the National Cancer Institute's population‐based Surveillance, Epidemiology, and End Results (SEER) Program between 1973 and 2004 were investigated by age (ages 0‐24 years, 25‐59 years, and 60 to ≥85 years), race, sex, pathology subtype, stage, and anatomic site.

RESULTS:

There were large differences in incidence and survival rates by age. There was a high percentage of osteosarcoma with Paget disease and osteosarcoma as a second or later cancer among the elderly. There was a high percentage of osteosarcoma among patients with Paget disease and osteosarcoma as a second or later cancer among the elderly. Tumor site differences among age groups were noted. Survival rates varied by anatomic site and disease stage and did not improve significantly from 1984 to 2004.

CONCLUSIONS:

This comprehensive, population‐based description of osteosarcoma, identified important differences in incidence, survival, pathologic subtype, and anatomic site among age groups, and quantified the impact of osteosarcoma in patients with Paget disease or as a second cancer on incidence and mortality rates. These findings may have implications in understanding osteosarcoma biology and epidemiology. Cancer 2009. © 2009 American Cancer Society.
Color, arousal, and performance—A comparison of three experiments
Authors: Küller Rikard , Mikellides Byron , Janssens Jan
Published: February 2009

Three studies of the psychological and physiological effects on people of colored room interiors are described. Experiment 1 compared a colorful and a gray room, whereas in experiments 2 and 3 red and blue rooms were compared. The results indicate that the color of an interior space will have effects on many different levels. The perception of the room itself was affected, and the colors also had an impact on the emotions and physiology of those who stayed in the rooms. Strong, especially red, colors and patterns put the brain into a more excited state, sometimes to such an extent as to cause a paradoxical slowing of the heart rate. Introvert persons, as well as those already in a negative mood, became more affected than others, which caused severe changes in their performance. The series of experiments described here were among the first to be carried out in full‐scale rooms painted or otherwise decorated in various colors. One practical implication is that a moderate use of good color design will serve to improve the overall mood and well‐being of people. In future research more emphasis should be placed on color, as just one component in the highly complex real‐life situations. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 141–152, 2009
Notes toward a verifiable vector algebraic basis for colorimetric modeling
Authors: Oulton David P.
Published: February 2009

The presented notes aim toward improved models of the scalar visual response to flat‐field stimuli, and are prompted by unease over the complexity of existing colour difference models. Some of the basic assumptions of colorimetry are examined in detail, and analytical methods whereby these assumptions can be investigated experimentally are presented. A key finding is that the standard CIE colorimetric model is verifiably correct as a predictor of point colour identity and metameric visual equivalence. It is however demonstrated to be a misleading basis for modeling colour difference, and an alternative scalar reference basis and experimental analysis method are presented. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 163–169, 2009
Proposal for selecting two‐color combinations with various affections. Part I: Introduction of the method
Authors: Nayatani Yoshinobu , Sakai Hideki
Published: February 2009

A method is proposed for selecting two‐color combinations with various feelings. Feelings used are pleasantness, contrast, floridness, warmth, and their combinations. The proposed method is given by its flow chart for selecting the candidates of two‐color combinations adapting to target feeling(s). The effectiveness of the proposed method is shown by the correlation coefficients between observed and predicted values for four kinds of feelings. Munsell H V/Cs of each component color are necessary for prediction; the prediction formulas are given for estimating the degree of each feeling for any two‐color combinations. The proposed method can be expanded to three‐color combinations. This proposal is expected to assist color designers, who can choose their usable color combinations from the candidates selected by the proposed method. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 128–134, 2009
An Ester‐Substituted Iridium Complex for Efficient Vacuum‐Processed Organic Light‐Emitting Diodes
Authors: Baranoff Etienne , Suarez Stéphane , Bugnon Philippe , Bolink Henk J. , Klein Cédric , Scopelliti Rosario , Zuppiroli Libero , Grätzel Michael , Nazeeruddin Mohammad K.
Published: February 2009

Red OLED: An orange–red‐emitting iridium complex (N958) was prepared, and its photophysical and device‐based characteristics were investigated. Despite N958 displaying quite poor photophysical properties in solution (acetonitrile), organic light‐emitting diode (OLED) devices based on the complex exhibit an efficiency close to 10 %.

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Subtyping dietary restraint and negative affect in a longitudinal community sample of girls
Authors: Chen Eunice Y. , McCloskey Michael S. , Keenan Kathryn E.
Published: February 2009

Objective:

This study tests the validity of the “dietary‐depressive” subtype (typified by greater negative affect) and a “dietary” subtype (typified by dietary restraint only) using a diverse longitudinal community sample.

Method:

Girls at ages 10, 12, and 14 completed the Child Eating Attitudes Test, the Child Symptom Inventory‐4, and Body Image Measure. Body Mass Index was assessed at each age.

Results:

Unlike previous studies, cluster analysis revealed an at‐risk “dietary‐depressive” (R+) subtype (18.7%,100/534) and a not at‐risk (R−) subtype, distinguished by few depressive symptoms and little dietary restraint (81.3%,434/534), but no “dietary” subtype. When compared with the R− subtype, the R+ subtype had significantly greater eating disordered behavior and attitudes. The R+ subtype at age 10 was a risk factor for binge‐eating but not obesity at ages 12 and 14.

Discussion:

Dietary restraint and depressive symptoms combined predict binge‐eating longitudinally in a diverse community sample of girls. Int J Eat Disord 2009. © 2009 by Wiley Periodicals, Inc.
Reproduction and offspring status 18 years after teenage‐onset anorexia nervosa—A controlled community‐based study
Authors: Wentz Elisabet , Gillberg I. Carina , Anckarsäter Henrik , Gillberg Christopher , Råstam Maria
Published: February 2009

Objective:

To study reproduction in a representative group of anorexia nervosa (AN) cases.

Method:

Fifty‐one adolescent‐onset AN cases (48 women; three men), originally recruited after community screening, and 51 matched comparison cases (COMP) were interviewed 18 years after AN onset at a mean age of 32 years, regarding pregnancies and early development of the children.

Results:

The results of the 48 AN and 48 COMP group women are reported in the present study. Six women still had an eating disorder (ED), none of whom had become a mother. Twenty‐seven women in the AN group and 31 women in the COMP group had children. Three women had an ED during pregnancy. Mean age at birth of the first child was lower in the AN group. Five AN women reported postpartum depression. Children in the AN group had significantly lower birth weight than the children in the COMP group. No other complications during pregnancy and the neonatal period differed across groups. Feeding difficulties were not overrepresented among the children of the AN group.

Discussion:

Adults who had recovered from teenage‐onset AN did not differ in most aspects from matched controls with respect to pregnancies and development of their offspring. © 2009 by Wiley Periodicals, Inc. Int J Eat Disord 2009
Biogeography of woody encroachment: why is mesquite excluded from shallow soils?
Authors: Eggemeyer Kathleen D. , Schwinning Susanne
Published: February 2009

While some studies aim to generalise the attributes of woody encroachers, examining their functional differences across biogeographic regions may also be instructive. Most of Texas is encroached byProsopis glandulosa, but on the eastern Edwards Plateau, a limestone plateau with thin soils,P. glandulosais rare andJuniperus asheiis dominant. We hypothesised thatP. glandulosais excluded from sites where bedrock at a depth of 1 m or less restricts the development of taproots, thus rendering this normally deep‐rooted species too vulnerable to drought. To test this idea, we monitored the physiological status of the two species on a site where both species were encroaching and the soil was 1·5–2·5 m deep, thus relatively deep for the Edwards Plateau region but not for regions whereP. glandulosadominates. Data were collected across three tree size classes from May to November 2006. Stem water potentials were similar across species and water potentials and photosynthetic rates decreased with tree size. Based on isotopic evidence, the effective rooting depth ofP. glandulosaincreased with tree size, but not inJ. ashei. P. glandulosahad a higher rate of leaf gas exchange overall as expected for a drought‐avoider; except for large trees during a summer drought, when species differences in photosynthesis rates diminished and the stomatal conductance forJ.asheiexceeded that ofP. glandulosa. We speculate that restrictions of soil depth may limit the invasiveness ofP. glandulosain part through negative effects on large trees, which may lower fecundity. Copyright © 2009 John Wiley & Sons, Ltd.
Signaling events leading to the curative effect of cystatin on experimental visceral leishmaniasis: Involvement of ERK1/2, NF‐κB and JAK/STAT pathways
Authors: Kar Susanta , Ukil Anindita , Das Pijush K.
Published: February 2009

Curative effect of cystatin, a natural cystein protease inhibitor, on experimental visceral leishmaniasis was associated with strong upregulation of iNOS. The transductional mechanisms underlying this cellular response was investigated in the murine macrophage cell line RAW 264.7 and in the BALB/c mouse model of visceral leishmaniasis. Cystatin synergizes with IFN‐γ in inducing ERK1/2 phosphorylation and NF‐κB DNA‐binding activity. Pretreatment of cells with specific inhibitors of NF‐κB or ERK1/2 pathway blocked the cystatin plus IFN‐γ‐inducible NF‐κB activity and markedly reduced the expression of iNOS at both mRNA and protein levels. Silencing of mitogen‐ and stress‐activated protein kinase 1 significantly reduced cystatin‐mediated NF‐κB‐dependent iNOS gene transcription suggesting the involvement of mitogen‐ and stress‐activated protein kinase 1 activation in ERK1/2 signaling. DNA binding as well as silencing experiments revealed the requirement of IFN‐γ‐mediated JAK‐STAT activation even though cystatin did not modulate this signaling cascade by itself. In the in vivo situation, key steps in the activation cascade of NF‐κB, including nuclear translocation of NF‐κB subunits, IκB phosphorylation and IκB kinase, are all remarkably enhanced in Leishmania‐infected mice by cystatin. Understanding the molecular mechanisms through which cystatin modulates macrophage effector responses will contribute to better define its potential for macrophage‐associated diseases, in general.
Severe functional impairment and elevated PD‐1 expression in CD1d‐restricted NKT cells retained during chronic HIV‐1 infection
Authors: Moll Markus , Kuylenstierna Carlotta , Gonzalez Veronica D. , Andersson Sofia K. , Bosnjak Lidija , Sönnerborg Anders , Quigley Máire F. , Sandberg Johan K.
Published: February 2009

Invariant CD1d‐restricted NKT cells play important roles in regulating both innate and adaptive immunity. They are targeted by HIV‐1 infection and severely reduced in number or even lost in many infected subjects. Here, we have investigated the characteristics of NKT cells retained by some patients despite chronic HIV‐1 infection. NKT cells preserved under these circumstances displayed an impaired ability to proliferate and produce IFN‐γ in response to CD1d‐restricted lipid antigen as compared with cells from uninfected control subjects. HIV‐1 infection was associated with an elevated expression of the inhibitory programmed death‐1 (PD‐1) receptor (CD279) on the CD4− subset of NKT cells. However, blocking experiments indicated that the functional defects in NKT cells were largely PD‐1‐independent. Furthermore, the elevated PD‐1 expression and the functional defects were not restored by anti‐retroviral treatment, and the NKT cell numbers in blood did not recover significantly in response to treatment. The functional phenotype of NKT cells in these patients suggests an irreversible immune exhaustion due to chronic activation in vivo. The data demonstrate a severe functional impairment in the remaining NKT‐cell compartment in HIV‐1‐infected patients, which limits the prospects to mobilize these cells in immunotherapy approaches in patients.
A regulatory cross‐talk between Vγ9Vδ2 T lymphocytes and mesenchymal stem cells
Authors: Martinet Ludovic , Fleury‐Cappellesso Sandrine , Gadelorge Mélanie , Dietrich Gilles , Bourin Philippe , Fournié Jean‐Jacques , Poupot Rémy
Published: February 2009

The physiological functions of human TCRVγ9Vδ2+ γδ lymphocytes reactive to non‐peptide phosphoantigens contribute to cancer immunosurveillance and immunotherapy. However, their regulation by mesenchymal stem cells (MSC), multipotent and immunomodulatory progenitor cells able to infiltrate tumors, has not been investigated so far. By analyzing freshly isolated TCRVγ9Vδ2+ lymphocytes and primary cell lines stimulated with synthetic phosphoantigen or B‐cell lymphoma cell lines in the presence of MSC, we demonstrated that MSC were potent suppressors of γδ‐cell proliferation, cytokine production and cytolytic responses in vitro. This inhibition was mediated by the COX‐2‐dependent production of prostaglandin E2 (PGE2) and by MSC through EP2 and EP4 inhibitory receptors expressed by Vγ9Vδ2 T lymphocytes. COX‐2 expression and PGE2 production by MSC were not constitutive, but were induced by IFN‐γ and TNF‐α secreted by activated Vγ9Vδ2 T cells. This regulatory cross‐talk between MSC and Vγ9Vδ2 T lymphocytes involving PGE2 could be of importance for the antitumor and antimicrobial activities of γδ T cells.
Late Transition‐Metal Complexes of 2‐Ph2PC6H4NHC(O)CH2NHCO2Bz: Observation of Three Distinct Ligation Modes (κ1‐P,κ2‐P/N and κ3‐P/N/N′)
Authors: Elsegood Mark R. J. , Lake Andrew J. , Smith Martin B.
Published: February 2009

The one‐step synthesis of the amide‐functionalised tertiary phosphane 2‐Ph2PC6H4NHC(O)CH2NHCO2Bz (Bz = CH2Ph), 2·HH, by condensation of the known aminophosphane, 2‐Ph2PC6H4(NH2) (1), with N‐(benzyloxycarbonyl)glycine and dicyclohexylcarbodiimide (DCC) in THF at room temperature is reported. The new ligand 2·HH displays various coordination modes when complexed to a range of late transition‐metal precursors. Hence κ1‐P‐coordination for 2·HH is observed in the complexes ClAu(2·HH) (3), MCl2(η5‐Cp*)(2·HH) (M = Rh 4; Ir 5), RuCl2(η6‐p‐cymene)(2·HH) (6), Pd(κ2‐CN‐C12H12N)Cl(2·HH) (7) and MCl2(2·HH)2 (M = Pd 8; Pt 9). Treatment of 8 or 9 with tBuOK in CH3OH gave the bis‐κ2‐P/N‐chelate complexes cis‐M{2‐Ph2PC6H4NC(O)CH2NHCO2Bz}2 (M = Pt 10; Pd 11) in which both monoanionic ligands 2·H– are disposed in a cis geometry. The relatednickel(II) complex cis‐Ni{2‐Ph2PC6H4NC(O)CH2NHCO2Bz}2 (12) was prepared from NiCl2·6H2O, 2 equiv. of 2·HH and tBuOK in refluxing CH3OH. Reaction of the piano‐stool complex 5 with tBuOK in CH3OH gave the chiral‐at‐metal complex Ir(η5‐Cp*){2‐Ph2PC6H4NC(O)CH2NCO2Bz} (14), present in solution as two diastereomers. A single‐crystal X‐ray diffraction study of 14 confirmed the κ3‐P/N/N′‐tridentate coordination mode. Under similar conditions the chiral‐at‐metal ruthenium(II) complex Ru(η6‐p‐cymene){2‐Ph2PC6H4NC(O)CH2NCO2Bz} (15) was prepared in which 22– functions efficiently as a dianionic tridentate ligand. All new compounds have been characterised by multinuclear NMR [31P{1H}, 1H], FT‐IR, EI‐MS, ES‐MS and microanalysis. Furthermore, the X‐ray structures of ten compounds have been determined and reveal, in the majority of cases, a strong propensity for the –NHC(O)CH2NHCO2Bz group to engage in N–H···N, N–H···O and N–H···Cl hydrogen bonding.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Synthesis and Study of 5,5′‐Bibenzimidazolylidenes and Their Bimetallic Complexes
Authors: Er Joyce A. V. , Tennyson Andrew G. , Kamplain Justin W. , Lynch Vincent M. , Bielawski Christopher W.
Published: February 2009

A new, high‐yielding synthesis of 3,3′,4,4′‐tetrachlorobiphenyl was developed, facilitating access to a new family of fluorescent 5,5′‐bibenzimidazolium salts bearing phenyl or bulky tertiary alkyl N‐substituents. Deprotonation of these salts afforded the respective 5,5′‐bibenzimidazolylidenes in excellent isolated yields (≥86 %), which were characterized in the solid state and solution. Treatment of these ditopic ligands with [Rh(COD)Cl]2 (COD = 1,5‐cyclooctadiene) afforded bimetallic complexes composed of two Rh atoms connected through a bis(carbene) linker. Electrochemical analyses of these complexes revealed single, quasi‐reversible oxidations at E1/2 = +0.54 to +0.59 V (vs. SCE) arising from the RhI/II redox couples. A bimetallic Rh carbonyl complex bearing a 5,5′‐bibenzimidazolylidene was also synthesized and found to exhibit νCO signals similar to a monotopic analogue. Collectively, these results suggested that the two metal centers in the aforementioned bimetallic complexes were electronically decoupled. These observations were supported by the crystal structures of one of the 5,5′‐bibenzimidazolium salts and its bis(carbene) derivative, which revealed relatively large dihedral angles of 51.2° and 47.8°, respectively, between the two aryl systems. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
The Smallest Vicinal Tricarbonyl Compound as a Monohydrate and Tetracarbonyl Compound as a Thiane Derivative – First Effective Synthesis, Characterization and Chemistry
Authors: Goswami Shyamaprosad , Maity Annada C. , Fun Hoong‐Kun , Chantrapromma Suchada
Published: February 2009

An effective synthesis of 2‐oxo‐1,3‐propanedial monohydrate or mesoxaldehyde (6a) and the first synthesis of 2,3‐dioxo‐1,4‐butanedial (18) as a thiane derivative are reported. These first members of the smallest vicinal tri‐ and tetracarbonyl compounds are stabilized by conversion to thiane derivatives 8, 9, 10, 11, 12, 15 and 19, which can be isolated as long‐lived compounds at room temperature. The structures of these novel thianes 8, 10, 12 and 15 were confirmed by their X‐ray crystal structures. The synthesis of a series of protected as well as free heterocyclic aldehydes (pterins and quinoxalines) by the use of the appropriate tricarbonyl compounds is also reported. Additionally, a one‐step synthetic strategy to prepare a series of different biheterocycles with the smallest vicinal tetracarbonyl compound is demonstrated.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
A Simple Organocatalytic Enantioselective Synthesis of Pregabalin
Authors: Bassas Oriol , Huuskonen Juhani , Rissanen Kari , Koskinen Ari M. P.
Published: February 2009

This paper describes a new procedure for the enantioselective synthesis of the important anticonvulsant drug Pregabalin, which shows biological properties as the (S) enantiomer only. The key step of the synthetic sequence is the Michael addition reaction of Meldrum's acid to a nitroalkene mediated by a quinidine derived thiourea. A variety of novel catalysts bearing different groups at the thiourea moiety were synthesized and tested. The most successful catalyst that incorporates a trityl substituent provided up to 75 %eeof (S)‐4. The conjugate addition reaction was carried out on a multigram scale with low loadings of catalyst (10 mol‐%). Moreover, the catalyst can be recycled showing the same capability in chemical yield and asymmetric induction. Then, hydrogenation of nitroalkane4followed by decarboxylation of diacid5provides Pregabalin hydrochloride in 59 % overall yield. Enantioenrichment by crystallization of the free amino acid1improves the (S)/(R) enantiomeric ratio to 9:1.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Perceived political self‐efficacy: Theory, assessment, and applications
Authors: Caprara Gian Vittorio , Vecchione Michele , Capanna Cristina , Mebane Minou
Published: February 2009

Political efficacy is addressed within the framework of social cognitive theory and a new measure to assess perceived political self‐efficacy is presented. Three studies document the validity of the new scale of measurement. The first study (N = 1673) examined the psychometric properties of the scale in accordance with classical test theory. This led to the identification of a unidimensional factor structure, including perceived political self‐efficacy in promoting one's own political opinion, in sustaining the political programs of the party to which one belongs, and in monitoring one's own political representatives' commitment. The second study (N = 632) further confirmed the internal and construct validity of the scale; criterion validity was also investigated using several indicators of political interest and participation. The third study (N = 1176) showed that politicians holding offices have higher levels of perceived political self‐efficacy than partisans and voters, further corroborating the criterion validity of the scale. Copyright © 2009 John Wiley & Sons, Ltd.
Theoretical and Experimental Study of the Homogeneous Catalytic Oxidation of Nicotinamide Adenine Dinucleotide (NADH) at Spherical Gold Electrodes Using Linear Sweep Voltammetry and Chronopotentiometry
Authors: Molina Ángela , González Joaquín , López‐Tenés Manuela , Soto Carmen M.
Published: February 2009

The homogeneous catalytic oxidation of coenzyme nicotinamide adenine dinucleotide (NADH) with dopamine at a thiolactic acid modified gold spherical electrode of radius 0.0128 cm has been studied in aqueous phosphate media (pH 7.0) using linear sweep voltammetry and chronopotentiometry with power time and exponential time currents. We have proved that, under the conditions of this study, the steady state is reached, in such a way that the expressions for the I−E and dI/dE−E responses are simplified and become independent of time and the electrochemical technique employed. Therefore, the experimental I−E and dI/dE−E curves obtained in chronopotentiometry and linear sweep voltammetry are practically superimposable and, from easy expressions for the peak parameters of the dI/dE−E curves deduced in this paper, values of the chemical and electrochemical rate constants have been obtained.
Fabrication of a Highly Sensitive Glucose Biosensor Based on Immobilization of Osmium Complex and Glucose Oxidase onto Carbon Nanotubes Modified Electrode
Authors: Salimi Abdollah , Kavosi Begard , Hallaj Rahman , Babaei Ali
Published: February 2009

In this research a novel osmium complex was used as electrocatalyst for electroreduction of oxygen and H2O2 in physiological pH solutions. Electroless deposition at a short period of time (60 s), was used for strong and irreversible adsorption of 1,4,8,12‐tetraazacyclotetradecane osmium(III) chloride (Os(III)LCl2) ClO4 onto single‐walled carbon nanotubes (SWCNTs) modified GC electrode. The modified electrode shows a pair of well defined and reversible redox couple, Os(IV)/Os(III) at wide pH range (1–8). The glucose biosensor was fabricated by covering a thin film of glucose oxidase onto CNTs/Os‐complex modified electrode. The biosensor can be used successfully for selective detection of glucose based on the decreasing of cathodic peak current of oxygen. The fabricated biosensor shows high sensitivity, 826.3 nA μM−1cm−2, low detection limit, 56 nM, fast response time <3 s and wide calibration range 1.0 μM–1.0 mM. The biosensor has been successfully applied to determination of glucose in human plasma. Because of relative low applied potential, the interference from electroactive existing species was minimized, which improved the selectivity of the biosensor. The apparent Michaelis‐Menten constant of GOx on the nanocomposite, 0.91 mM, exhibits excellent bioelectrocatalytic activity of immobilized enzyme toward glucose oxidation. Excellent electrochemical reversibility, high stability, technically simple and possibility of preparation at short period of time are of great advantages of this glucose biosensor.
Electrochemical Detection of Asymmetric PCR Products by Labeling with Osmium Tetroxide
Authors: Mix Maren , Reske Thomas , Duwensee Heiko , Flechsig Gerd‐Uwe
Published: February 2009

Single stranded DNA‐targets from asymmetric polymerase chain reaction (PCR) of a sequence of the gram positive, spore forming bacterium Clostridium acetobutylicum were detected by square‐wave voltammetry after labeling with osmium tetroxide bipyridine and hybridization with DNA capture probes immobilized on gold electrodes. The asymmetric PCR, performed with a 10‐fold excess of the forward‐primer, was used without any further purification for hybridization with protective strands and covalent labeling with osmium tetroxide bipyridine. Square‐wave voltammetric signals of 20 nmol/L targets were significantly higher at 50 °C compared with 23 °C hybridization temperature. A fully noncomplementary protective strand yielded thoroughly modified targets unable for further hybridization. Coupling this with thermal discrimination opens new opportunities for sequence specific DNA detection.
The EOF of polymer solutions
Authors: Olivares María L. , Vera‐Candioti Luciana , Berli Claudio L. A.
Published: February 2009

The EOF of polymer solutions is analysed in the framework of continuum fluid mechanics and the standard electrokinetic model. Two key aspects are taken into consideration: the non‐Newtonian character of the fluid and the polymer concentration near the interface, which greatly modify the fluid viscosity in the region where electroosmosis takes place. A satisfactory mathematical model is derived for the electroosmotic mobility of solutions that present polymer depletion at the wall. The case of solutions containing polymers that adsorb onto the wall is briefly reviewed, and a preliminary approach is discussed for the limit of strong polymer adsorption. In order to illustrate the theoretical discussions, experimental data obtained from aqueous solutions of carboxymethyl cellulose in fused‐silica capillaries are presented. Relevant results are observed, which are appropriately captured by the modelling proposed. The fundamental phenomena discussed in this work are of interest in microfluidics and electrophoresis.
Bioanalytical separations using electric field gradient techniques
Authors: Meighan Michelle M. , Staton Sarah J. R. , Hayes Mark A.
Published: February 2009

The field of separations science will be strongly impacted by new electric‐field‐gradient‐based strategies. Many new capabilities are being developed with analytical targets ranging from particles to small molecules, and soot to living cells. Here we review the emerging area of electric field gradient techniques, dividing the large variety of techniques by the target of separation. In doing so, we have contributions using dielectrophoresis, electric field gradient focusing (including dynamic, true moving bed, and pulsed field), electrocapture and electrophoretic focusing, temperature gradient focusing, and focusing with centrifugal force. We cover the literature from the start of 2007 to June 2008, along with some introductory discussions. Even with the relatively short time frame, this young and dynamic field of inquiry produced some 100 contributions describing new and unique techniques and several new applications.
Analysis of charge heterogeneities in mAbs using imaged CE
Authors: He Xiaoping Z. , Que Amy H. , Mo Jim J.
Published: February 2009

An analytical method using the imaged CE (iCE) technology has been developed and validated for measuring contents of charge variants for mAb molecules. The method could generate similar information that require both conventional IEF electrophoresis and ion exchange liquid chromatography to generate as an iCE analysis would produce both the pI of the molecules and quantitative contents of charge variants. Thus, it offers unique advantages over the IEF and ion exchange methods in terms of identification, separation and quantitation of charge variants. The data presented in this study demonstrated that the iCE method is suitable not only for research purposes but also for quality control purpose of mAb clinical or commercial manufacture as the technique can be validated and possesses sufficient robustness. The developed generic iCE method has been tested for a wide range of therapeutic mAbs and proved its suitability for multiple mAb molecules. The tested mAbs are a group of molecules with a wide range of charge compositions (acidic species ranging from 10 to 70%) and a diverse range of pI of 6.9–9.6. Developing platform analytical technologies is an efficient way to meet the demand of rapid growth of therapeutic mAb candidates under clinical and preclinical development. The iCE technology is a good candidate to become a platform method as it could cover a broad range of pH gradient. The experiences learned during the developmental process would provide important and valuable information to the biotech industry for the evaluation of charge heterogeneity of mAbs in terms of release testing, characterization, stability study, process development support and comparability study.
Determination of the surface heat‐transfer coefficient in CE
Authors: Hruska Vlastimil , Evenhuis Christopher J. , Guijt Rosanne M. , Macka Miroslav , Gas Bohuslav , Marriott Philip J. , Haddad Paul R.
Published: February 2009

A knowledge of the heat‐transfer coefficient, hs, for the external surface of the capillary or the overall heat coefficient, hOA, is of great value in predicting the mean increase in temperature of the electrolyte, ΔTMean, during electrokinetic separations. For CE, traditional indirect methods of determining hs were time‐consuming and tended to overestimate cooling efficiency; a novel method is introduced, which is based on curve‐fitting of plots of conductance versus voltage to calculate several important parameters including ΔTMean, hs, the conductance free of Joule heating effects (G0) and the voltage that causes autothermal runaway, Vlim. The new method is superior to previously published methods in that it can be performed more quickly and that it corrects for systematic errors in the measurement of electric current for voltages <5 kV. These errors tended to exaggerate the cooling efficiency of commercial instruments so that the calculated increases in electrolyte temperature were smaller than their actual values. Axially averaged values for hs were determined for three different commercial CE instruments ranging from 164 W m−2 K−1 for a passively cooled instrument in a drafty environment to 460 W m−2 K−1 for a liquid‐cooled instrument.
Two variable semi‐empirical and artificial neural‐network‐based modeling of peptide mobilities in CZE: The effect of temperature and organic modifier concentration
Authors: Mittermayr Stefan , Chovan Tibor , Guttman András
Published: February 2009

This work was focused on investigating the effects of two separation influencing parameters in CZE, namely temperature and organic additive concentration upon the electrophoretic migration properties of model tripeptides. Two variable semi‐empirical (TVSE) models and back‐propagation artificial neural networks (ANN) were applied to predict the electrophoretic mobilities of the tripeptides with non‐polar, polar, positively charged, negatively charged and aromatic R group characteristics. Previously published work on the subject did not account for the effect of temperature and buffer organic modifier concentration on peptide mobility, in spite of the fact that both were considered to be influential factors in peptide analysis. In this work, a substantial data set was generated consisting of actual electrophoretic mobilities of the model tripeptides in 30 mM phosphate buffer at pH 7.5, at 20, 25, 30, 35 and 40°C and at four different organic additive containing running buffers (0, 5, 10 and 15% MeOH) applying two electric field strengths (12 and 16 kV) to assess our mobility predicting models. Based on the Arrhenius plots of natural logarithm of mobility versus reciprocal absolute temperature of the various experimental setups, the corresponding activation energy values were derived and evaluated. Calculated mobilities by TVSE and back‐propagation ANN models were compared with each other and to the experimental data, respectively. Neural network approaches were able to model the complex impact of both temperature and organic additive concentrations and resulted in considerably higher predictive power over the TVSE models, justifying that the effect of these two factors should not be neglected.
Requirement of the Saccharomyces cerevisiae APN1 gene for the repair of mitochondrial DNA alkylation damage
Authors: Acevedo‐Torres Karina , Fonseca‐Williams Sharon , Ayala‐Torres Sylvette , Torres‐Ramos Carlos A.
Published: February 2009

The Saccharomyces cerevisiae APN1 gene that participates in base excision repair has been localized both in the nucleus and the mitochondria. APN1 deficient cells (apn1Δ) show increased mutation frequencies in mitochondrial DNA (mtDNA) suggesting that APN1 is also important for mtDNA stability. To understand APN1‐dependent mtDNA repair processes we studied the formation and repair of mtDNA lesions in cells exposed to methyl methanesulfonate (MMS). We show that MMS induces mtDNA damage in a dose‐dependent fashion and that deletion of the APN1 gene enhances the susceptibility of mtDNA to MMS. Repair kinetic experiments demonstrate that in wild‐type cells (WT) it takes 4 hr to repair the damage induced by 0.1% MMS, whereas in the apn1Δ strain there is a lag in mtDNA repair that results in significant differences in the repair capacity between the two yeast strains. Analysis of lesions in nuclear DNA (nDNA) after treatment with 0.1% MMS shows a significant difference in the amount of nDNA lesions between WT and apn1Δ cells. Interestingly, comparisons between nDNA and mtDNA damage show that nDNA is more sensitive to the effects of MMS treatment. However, both strains are able to repair the nDNA lesions, contrary to mtDNA repair, which is compromised in the apn1Δ mutant strain. Therefore, although nDNA is more sensitive than mtDNA to the effects of MMS, deletion of APN1 has a stronger phenotype in mtDNA repair than in nDNA. These results highlight the prominent role of APN1 in the repair of environmentally induced mtDNA damage. Environ. Mol. Mutagen., 2009. © 2009 Wiley‐Liss, Inc.
Areca nut‐induced micronuclei and cytokinesis failure in Chinese hamster ovary cells is related to reactive oxygen species production and actin filament deregulation
Authors: Lin Chiu‐Chun , Chang Mei‐Chi , Chang Hsiao‐Hua , Wang Tong‐Mei , Tseng Wan‐Yu , Tai Tseng‐Fang , Yeh Hung‐Wei , Yang Ting‐Ting , Hahn Liang‐Jiunn , Jeng Jiiang‐Huei
Published: February 2009

Epidemiological studies have shown a strong association between environmental exposure to betel quid (BQ) and oral cancer. Areca nut (AN), an ingredient of BQ, contains genotoxic and mutagenic compounds. In this study, we found that AN extract (ANE) inhibited the growth of Chinese hamster ovary cells (CHO‐K1) in a dose‐ and time‐dependent manner. Intracellular reactive oxygen species (ROS) levels and micronuclei (MN) frequency were significantly increased following ANE treatment in CHO‐K1 cells. Addition of catalase markedly inhibited ANE‐induced MN formation, indicating that ANE‐induced genotoxicity was correlated with intracellular H2O2. Incubation of CHO‐K1 cells with ANE (400–800 μg/ml) for 24 hr caused G2/M arrest, and prolonged exposure to ANE (800 μg/ml) significantly induced cell death. Surprisingly, ANE itself caused cytokinesis failure and subsequent increase in binucleated cell formation. Coexposure to catalase (2,000 U/ml) and ANE (800 μg/ml) reduced the generation of binucleated cells, indicating that ANE‐induced cytokinesis failure was associated with oxidative stress. Following prolonged exposure to ANE, an accumulation of hyperploid/aneuploid cells concomitant with bi‐, micro‐ or multinucleated cells was found. In summary, our results demonstrate that ANE exposure to CHO‐K1 cells caused increased MN frequency, G2/M arrest, cytokinesis failure, and an accumulation of hyperploid/aneuploid cells. These events are associated with an increase in intracellular H2O2 level and actin filament disorganization. Environ. Mol. Mutagen., 2009. © 2009 Wiley‐Liss, Inc.
Apoptosis induction in human lung adenocarcinoma cells by oil‐soluble allyl sulfides: Triggers, pathways, and modulators
Authors: Wu Xin‐Jiang , Hu Ying , Lamy Evelyn , Mersch‐Sundermann Volker
Published: February 2009

DAS (diallyl sulfide), DADS (diallyl disulfide), and DATS (diallyl trisulfide) are major oil‐soluble allyl sulfides (OAS) that represent major garlic constituents. The anticarcinogenic and antimutagenic effects of these substances have been extensively studied during the last decades. Previous reports suggest that induction of apoptosis by OASs might contribute to their chemopreventive effects. In this study, we report that OASs DADS and DATS induce significant apoptosis in human lung adenocarcinoma A549 cells, whereas DAS does not. Differential modulation of reactive oxygen intermediates (ROI) and mitochondria membrane potential (MMP) may account for the apoptotic effects of DADS and DATS. The underlying molecular mechanisms of apoptosis induction by both compounds include activation of C‐Jun N‐terminal kinase (JNK), up‐regulation of p53, and down‐regulation of bcl‐2 expression. In our test series, up‐regulation of extracellular signal‐regulated protein kinase (ERK) was dispensable for apoptosis induction; DAS, DADS, or DATS did not modify expression of MAPK p38, bax, and bcl‐xL. Further investigation revealed that the specific JNK inhibitor SP600125 and the antioxidant NAC blocked DADS and DATS‐induced apoptosis, whereas ERK inhibitors did not. Additionally, our data provide the first evidence that Fas‐mediated cell death pathway is partly involved in DADS but not DATS‐mediated cell death. Taken together, our work has elucidated the triggers, important modulators, and signal transduction pathways in DADS and DATS‐mediated apoptosis. Environ. Mol. Mutagen., 2009. © 2009 Wiley‐Liss, Inc.
Antioxidant and pro‐oxidant capacities of ITCs
Authors: Valgimigli Luca , Iori Renato
Published: February 2009

Isothiocyanates (ITCs) are breakdown products of glucosinolates contained in cruciciferous vegetables. This heterogeneous family of molecules has the NCS group as its common structural feature and possesses important cytoprotective properties. Their biological interactions are strongly related to modulation of cellular redox status, and a number of studies have documented their indirect antioxidant properties, particularly related to induction of phase‐2 enzymes. On the other hand, some direct antioxidant behavior has also been observed for a limited number of ITCs. Paradoxically relevant pro‐oxidant properties have also been documented, possibly related to the simultaneous induction of phase‐1 enzymes. In this review, we will summarize and discuss the prevailing mechanisms for the antioxidant and pro‐oxidant activity of ITCs, both in vivo and in vitro. Environ. Mol. Mutagen., 2009. © 2009 Wiley‐Liss, Inc.
Analysis of cellular response to isocyanate using N‐succinimidyl N‐methylcarbamate exposure in cultured mammalian cells
Authors: Mishra Pradyumna Kumar , Gorantla Venkata Raghuram , Akhtar Nabila , Tamrakar Priyanka , Jain Subodh Kumar , Maudar Kewal Krishan
Published: February 2009

Isocyanates (RNCO), one of the highly reactive industrial intermediates, possess the capability to modulate the bio‐molecules by forming toxic metabolites and adducts which may cause adverse health effects. Some of their toxic degradations have previously been unknown and overlooked; of which, molecular repercussions underlying their genetic hazards upon occupational/accidental exposures still remain as an intricate issue and are hitherto unknown. To assess the genotoxic potential of methyl isocyanate in cultured mammalian cells after in vitro exposure, we performed a study in three different normal cell lines MM55.K (mouse kidney epithelial), B/CMBA.Ov (mouse ovarian epithelial), and NIH/3T3 (primary mouse embryonic fibroblast). Cellular DNA damage response was studied for qualitative phosphorylation states of ATM, γH2AX proteins and quantitative state of p53 phosphorylation; DNA cell cycle analysis and measure of cellular apoptotic index before and after treatment were also investigated. Our results demonstrate that methyl isocyanate by negatively regulating the DNA damage response pathway, might promote cell cycle arrest, and apoptosis in cultured mammalian cells suggestive of causing genetic alterations. We anticipate that these data along with other studies reported in the literature would help to design better approaches in risk assessment of occupational and accidental exposure to isocyanates. We also predict that increasing knowledge on DNA damage‐triggered signaling leading to cell death could provide new strategies for investigating the effects of DNA repair disorders and decreased repair capacity on the toxicity and carcinogenic properties of environmental toxins. Environ. Mol. Mutagen., 2009. © 2009 Wiley‐Liss, Inc.
Human impact on fixed sand dunes revealed by morphometric analysis
Authors: Kiss Tímea , Sipos György , Kovács Ferenc
Published: February 2009

The Nyírség is the second largest alluvial fan in Hungary covered by fixed sand dunes. The primary aim of the paper is to describe the morphology of dunes in the region and classify them based on their morphometric characteristics. The other major aim is to select those dunes which were exposed to significant anthropogenic impact, and to determine the spatial and temporal differences in the intensity of human activity. The following dune types were separated: valley‐marginal, transitional valley‐marginal, transitional parabolic, filled, partially and unfilled parabolic dunes. After defining different dune types and their parameters, certain dunes were selected based on exposure to significant anthropogenic impact. Definite connection was demonstrated between the intensity of human environmental impact and the rate of erosion on fixed sand dunes. The erosion of sand dunes was most intensive in Medieval times, most likely due to concentration of agricultural land use. Copyright © 2009 John Wiley & Sons, Ltd.