bluuebunny/crossref_metadata_2025 huggingface dataset:
Sulfotransferases: Structure, Mechanism, Biological Activity, Inhibition, and Synthetic Utility
Authors: Chapman Eli , Best Michael D. , Hanson Sarah R. , Wong Chi‐Huey
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis and Modifications of Carbohydrates Using Biotransformations
Authors: Daines Alison M. , Maltman Beatrice A. , Flitsch Sabine L.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Asymmetric Catalysis in the Pharmaceutical Industry
Authors: Hawkins Joel M. , Watson Timothy J. N.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Creation of Molecular‐Assembling, ‐Stressing, and Converting Fields Based on Nanospaces of Metal Complexes
Authors: Uemura Takashi , Kitagawa Susumu
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
What Can We Expect from Mesoporous Materials in the Field of Heterogeneous Catalysis?
Authors: Iwamoto Masakazu
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Origin, Control, and Application of Supramolecular Chirogenesis in Bisporphyrin‐Based Systems
Authors: Borovkov Victor V. , Hembury Guy A. , Inoue Yoshihisa
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Metal Ion Modulated Electron Transfer in Photosynthetic Proteins
Authors: Utschig Lisa M. , Thurnauer Marion C.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Combined Spectroscopic/Computational Studies on Fe‐ and Mn‐Dependent Superoxide Dismutases: Insights into Second‐Sphere Tuning of Active Site Properties
Authors: Jackson Timothy A. , Brunold Thomas C.
Published: August 2004

For Abstract see ChemInform Abstract in Full Text.
Lung carcinoma symptoms—An independent predictor of survival and an important mediator of African‐American disparity in survival
Authors: Tammemagi C. Martin , Neslund‐Dudas Christine , Simoff Michael , Kvale Paul
Published: August 2004

BACKGROUND

The extent of disease in patients with lung carcinoma is reflected morphologically by stage and pathophysiologically by sign/symptoms. This study evaluates the associations between symptoms and stage, the independent impact of symptoms on survival, predictors of symptoms, and the extent to which symptoms mediate survival disparities.

METHODS

Data from 1154 patients with lung carcinoma were collected from the authors' tumor registry and by abstraction of medical records. Associations were evaluated by logistic and Cox regression analyses.

RESULTS

Symptomatic diagnoses were associated with advanced disease stage (odds ratio [OR], 4.53; 95% confidence interval [95%CI], 3.17–6.48). Hoarseness, hemoptysis, dyspnea, noncardiac chest pain, extrathoracic pain, neurologic symptoms, weight loss, and weakness/fatigue (adverse symptoms) were associated independently with relatively higher/advanced stage and/or reduced survival. Adverse symptoms (≥ 1 vs. 0) predicted reduced survival independently of stage and other prognosticators (hazard ratio [HR], 1.84; 95%CI, 1.52–2.21). Independent predictors of adverse symptoms included gender (ORmale vs. female, 1.50; 95%CI, 1.11–2.01), race/ethnicity (ORblack vs. white, 1.62; 95%CI, 1.18–2.21), and marital status (ORspouseless vs. not, 1.79; 95%CI 1.31–2.45). The hazard ratios (HR; black vs white), univariate, adjusted for stage, and adjusted for stage and adverse symptoms, was 1.206 (95%CI, 1.05–1.38), 1.165 (95%CI, 1.01–1.34), and 1.075 (95%CI, 0.94–1.26), respectively. Adverse symptoms explained 43% of race/ethnic survival disparity beyond stage.

CONCLUSIONS

Symptoms were associated with disease stage, yet both were important, independent predictors of survival; and symptoms explained an important amount of race/ethnic disparity in the survival of patients with lung carcinoma. Symptomatology needs to be incorporated into cancer clinical trials and into outcomes and disparities research. Cancer 2004. © 2004 American Cancer Society.
Solid‐State Reactions of AgAc with TabHPF6 at Room Temperature − Isolation and Structural Characterisation of an Unusual Octadecanuclear Silver Thiolate Cluster [Ag9(Tab)8(MeCN)8]2(PF6)18·4MeCN [Tab = 4‐(trimethylammonio)benzenethiolate]
Authors: Chen Jin‐Xiang , Xu Qing‐Feng , Xu Ying , Zhang Yong , Chen Zhong‐Ning , Lang Jian‐Ping
Published: August 2004

The room‐temperature solid‐state reaction of silver acetate with TabHPF6 [Tab = 4‐(trimethylammonio)benzenethiolate] followed by recrystallization from MeCN afforded a unique octadecanuclear silver thiolate complex [Ag9(Tab)8(MeCN)8]2(PF6)18·4MeCN (1). An X‐ray analysis of 1 revealed that the structure of [Ag9(Tab)8(MeCN)8]218+ contains an unprecedented tubular motif in which one central saddle‐shaped Ag6S6 fragment and two identical Ag5S6 fragments are interconnected by a pair of Ag atoms and four Ag−S bonds. The solid‐state product was assumed to be [Ag9(Tab)8]2(PF6)18 and might have the Ag18S16 core structure of 1 based on elemental analysis, IR spectroscopy, 1H NMR spectroscopy, luminescence spectra, XRD and TGA measurements. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Microwave‐Induced Polyol‐Process Synthesis of Copper and Copper Oxide Nanocrystals with Controllable Morphology
Authors: Zhao Yu , Zhu Jun‐Jie , Hong Jian‐Min , Bian Ningsheng , Chen Hong‐Yuan
Published: August 2004

Different morphologies of copper and copper oxide nanocrystallites, including radially arrayed whiskers, cubic particles and sphere particles, have been successfully synthesized by a microwave‐induced method under ambient conditions. In aqueous solution containing different ethylene glycol concentrations, copper acetate hydrate produces different reduction products. The as‐prepared copper and copper oxide crystallites were characterized by various techniques, including X‐ray powder diffraction, transmission electron microscopy, selected‐area electron diffraction and UV/Vis absorption spectroscopy. It was found that microwave irradiation plays a critical role in the formation of the products; temperature was also found to be important in the reaction. The irradiation time and copper acetate concentration also affect the morphology of the products. The possible formation mechanism is also discussed. ((c) Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Structural Studies of Mono‐ and Dimetallic MoVI Complexes − A New Mechanistic Contribution in Catalytic Olefin Epoxidation Provided by Oxazoline Ligands
Authors: Brito José A. , Gómez Montserrat , Muller Guillermo , Teruel Helena , Clinet Jean‐Claude , Duñach Elisabet , Maestro Miguel A.
Published: August 2004

New seven‐coordinate oxo(peroxo)molybdenum(VI) complexes with bidentate chiral oxazolines, anionic κ2‐N,O (V) and neutral κ2‐N,N (VI), have been prepared and fully characterised by NMR spectroscopy and single‐crystal X‐ray diffraction studies. Dimetallic dioxo(μ‐oxo)molybdenum(VI) compounds containing oxazolinylpyridine ligands II−IV have also been synthesised. NMR studies showed the presence of several isomers (up to six species) due to the Mo−O−Mo bridge angle and the unsymmetrical nature of the N,N ligand. The roles of mono‐ (I, V and VI) and dimetallic (II) oxomolybdenum(VI) complexes in the catalytic epoxidation of cyclooctene, norbornene and (R)‐limonene have been studied. The high activity of the oxomono(peroxo) precursor V containing the hemilabile oxazolinylphenolate, in contrast to the unexpected low activity for the oxobis(peroxo) species VI, could be justified by the inertness observed for the oxazolinylpyridine ligand. In addition, the dimetallic system II afforded high selectivity towards limonene epoxide formation (trans/cis‐10 ratio up to 9:1). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Homoleptic Rare‐Earth Carbazolates and the Trends of Their E Redox Potentials: Mixed‐Valent Samarium in 1∞[Sm2(Cbz)5](CbzH) (CbzH = carbazole) and Trivalent Thulium, Neodymium and Gadolinium in [Ln2(Cbz)6]
Authors: Müller‐Buschbaum Klaus , Quitmann Catharina C.
Published: August 2004

The solvent‐free melt reaction of carbazole (CbzH, C12H8NH) with samarium metal yields 1∞[Sm2(Cbz)5](CbzH) (1), whilst the melt reactions with thulium, neodymium and gadolinium give [Tm2(Cbz)6] (2), [Nd2(Cbz)6] (3) and [Gd2(Cbz)6] (4), respectively. Compounds 1 and 2 were obtained as single crystals and their crystal structures determined by single‐crystal X‐ray analysis, whilst 3 and 4 were obtained as powders. X‐ray powder diffraction studies show that the gadolinium‐containing complex 4 is isotypic to the thulium complex 2, whereas the neodymium‐containing complex 3 is not. Compound 1 contains alternating SmII and SmIII cations in a chain structure. Complex 2 only exhibits dimeric units of TmIII. Besides Ln−N coordination, the crystal structures of both compounds show η6‐π interactions with the phenyl rings of the carbazolate ligands. This leads to small coordination polyhedra, such as connected tetrahedra of two nitrogen atoms and two η6‐π‐coordinated phenyl rings around SmII, and trigonal bipyramids of five nitrogen atoms around SmIII for 1, as well as tetrahedra of three nitrogen atoms and one η6‐π‐phenyl interaction around TmIII for 2. From the trend of the E redox potentials, the complexes of neodymium and gadolinium are also trivalent. For 1−4 the results of FIR, MIR and Raman spectroscopy as well as simultaneous DTA/TG analyses are also presented. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Synthetic Applications of Intermolecular Cyclopropanation of Carboxylic Esters with Dialkoxytitanacyclopropane Reagents
Authors: Kulinkovich Oleg
Published: August 2004

The reaction of carboxylic esters with ethylmagnesium bromide in the presence of titanium(IV) isopropoxide, which leads to the formation of substituted cyclopropanols, was disclosed in the late 1980′s. The key organometallic intermediates in this transformation are diisopropoxytitanacyclopropane species, which act as 1,2‐dicarbanionic equivalents. The intermolecular titanium‐mediated cyclopropanation of carboxylic esters and subsequent transformation of the three‐membered ring provides a convenient and flexible approach to the construction of the carbon skeleton of organic molecules with ketone and other functionalities. Applications of this methodology to the synthesis of natural biologically active compounds and their analogues have been published over the last fifteen years and are summarized in the present review article. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Resources and alternatives in coalition formation: The effects on payoff, self‐serving behaviour, and bargaining length
Authors: Beest Ilja Van , Dijk Eric Van , Wilke Henk
Published: August 2004

A consistent finding in coalition research is that the payoff of coalition members is related to (a) the resources they contribute to the coalition, and to (b) the number of alternative coalitions they can form. These two factors are, however, often intertwined. A greater number of resources tends to go hand in hand with a greater number of alternatives, leaving unanswered how both factors affect coalition behaviour. This paper attempts to clarify the interplay of resources and alternatives by disentangling the two in a newly developed coalition paradigm. Results indicated that participants base their payoff allocation on both resources and alternatives, but suggest that self‐serving behaviour is more related to alternatives. Furthermore, resources and alternatives had a distinct effect on the bargaining process. It was shown that differences in alternatives led to longer bargaining. Copyright © 2004 John Wiley & Sons, Ltd.
Expectancy confirmation in spite of disconfirming evidence: The case of price increases due to the introduction of the Euro
Authors: Traut‐Mattausch Eva , Schulz‐Hardt Stefan , Greitemeyer Tobias , Frey Dieter
Published: August 2004

People in Germany overwhelmingly believe that the Euro introduction caused an overall price increase, however, no such increase actually took place. To investigate whether this disparity could be based on biased perceptions of the average price trend, four studies were conducted. Participants received two menus from a restaurant (one ‘old’ menu with German Mark (DM) prices and one ‘new’ menu with Euro prices) and were asked to estimate the price trend (in per cent). In all of these studies, price trend judgements were biased towards rising prices. If the prices had in fact been raised, the magnitude of this price increase was overestimated. If the prices had remained stable, significant price increases were perceived. And if the prices had fallen, they were perceived as having remained stable. The bias was systematically related to participants' expectations concerning price increases. A ‘selective outcome correction’ hypothesis proved to best fit the data: incorrect calculation outcomes that are in line with one's expectations are overlooked, whereas incorrect inconsistent outcomes are detected and corrected. The results imply that expectations can influence judgements even when clear disconfirming evidence is available that can be compared with an objective standard, thus leaving no room for interpretation. Copyright © 2004 John Wiley & Sons, Ltd.
Is affective material in attitudes more accessible than cognitive material? The moderating role of attitude basis
Authors: Giner‐Sorolla Roger
Published: August 2004

Verplanken, Hofstee, and Janssen (1998) found that the affective component of attitude is accessed more readily than the cognitive. Three studies further examined these findings in the light of two competing explanations: affective primacy, which states that emotional material is inherently more accessible than cognitive; and evaluative primacy, which states that emotional material is more accessible only if it is inherently more evaluative or supports the overall evaluative basis of attitude. Study 1 measured the accessibility of cognitive and affective traits while equalizing the evaluative nature of these traits. This study found a speed advantage for affective traits, but the attitude objects in this study turned out to be mainly affectively based. Studies 2 and 3, using a mixture of affectively and cognitively based objects, found that the speed advantage for affective terms was only found among affectively based objects; Study 3 also found a speed advantage for cognitive terms among cognitively based objects, and additionally found that individual differences in attitude basis explained part of this interaction. Collectively, these studies show that while affective material may be accessed more quickly than cognitive, this is most true when overall evaluation is based on affect rather than cognition. Copyright © 2004 John Wiley & Sons, Ltd.
The impact of outreach on admissions to an adolescent anorexia nervosa inpatient unit
Authors: Jaffa Tony , Percival Jo
Published: August 2004

The development of an outreach service from a UK National Health Service inpatient unit for teenagers with anorexia nervosa seems to contribute to a reduced need for admission. This finding may have implications for other eating disorder services. Copyright © 2004 John Wiley & Sons, Ltd and Eating Disorders Association.
Can adolescents' perceptions of their weight be used in screening for eating disorders? A pilot study of a short screening questionnaire
Authors: Dring G. J. , Singlehurst P. , Hutton S.
Published: August 2004

A Short Screening Questionnaire (SSQ) was devised to select schoolgirls who are underweight but see themselves as overweight. It was predicted that this would identify girls with eating disorders. This was unsuccessful. A comparison was made with the Eating Attitude Test (EAT). Inaccuracy in self‐reports of weight and height may be a factor in the failure. Copyright © 2004 John Wiley & Sons, Ltd and Eating Disorders Association.
The influence of societal games on the methodology of evaluative inquiry
Authors: Smith Nick L.
Published: August 2004

Understanding evaluative strategies as activities conducted in the service of specific societal games clarifies methodological issues and facilitates method choices.
Informal logic and reasoning in evaluation
Authors: Blair J. Anthony
Published: August 2004

Informal logic in philosophy and evaluation share considerable common ground and can offer each other various opportunities for meaningful cross‐fertilization that can lead to advancements in theory and practice in both fields.
A multidimensional framework for conceptualizing human services integration initiatives
Authors: Konrad Ellen L.
Published: August 2004

The ability to define and understand the “black box” of human services integration initiatives is aided by a multidimensional, multilevel framework.
Methodological issues in evaluating integrated services initiatives
Authors: Knapp Michael S.
Published: August 2004

This chapter explores the conceptualization and design of studies that evaluate integrated services initiatives and suggests approaches for further evaluation of how these initiatives work and what they are accomplishing.
Evaluation of state‐level integrated services initiatives: Colorado's experience
Authors: Garnett Donna M. , Gould Marsha S.
Published: August 2004

The methodology and findings of two Colorado studies are described, followed by a synthesis of both evaluations and how they contribute to lessons learned in evaluating state‐level services integration initiatives.
A water setting tetracalcium phosphate–dicalcium phosphate dihydrate cement
Authors: Burguera E. F. , Guitián F. , Chow L. C.
Published: August 2004

The development of a calcium phosphate cement, comprising tetracalcium phosphate (TTCP) and dicalcium phosphate dihydrate (DCPD), that hardens in 14 min with water as the liquid or 6 min with a 0.25 mol/L sodium phosphate solution as the liquid, without using hydroxyapatite (HA) seeds as setting accelerator, is reported. It was postulated that reduction in porosity would increase cement strength. Thus, the effects of applied pressure during the initial stages of the cement setting reaction on cement strength and porosity were studied. The cement powder comprised an equimolar mixture of TTCP and DCPD (median particle sizes 17 and 1.7 μm, respectively). Compressive strengths (CS) of samples prepared with distilled water were 47.6 ± 2.4 MPa, 50.7 ± 4.2 MPa, and 52.9 ± 4.7 MPa at applied pressures of 5 MPa, 15 MPa, and 25 MPa, respectively. When phosphate solution was used, the CS values obtained were 41.5 ± 2.3 MPa, 37.9 ± 1.7 MPa, and 38.1 ± 2.3 MPa at the same pressure levels. Statistical analysis of the results showed that pressure produced an improvement in CS when water was used as liquid but not when the phosphate solution was used. Compared to previously reported TTCP–DCPD cements, the greater CS values and shorter setting times together with a simplified formulation should make the present TTCP–DCPD cement a useful material as a bone substitute for clinical applications. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 71A: 275–282, 2004
Rapid induction of the intrinsic apoptotic pathway by L‐glutamine starvation
Authors: Paquette Julie C. , Guérin Paul J. , Gauthier Eric R.
Published: August 2004

While the amino acid L‐glutamine is known to play a role in the survival of several cell types, the underlying molecular mechanisms are still poorly defined. We show in this report that L‐glutamine starvation rapidly triggered apoptosis in Sp2/0‐Ag14 hybridoma cells. This process involved the activation of both caspases‐9 and ‐3, suggesting that L‐glutamine deprivation initiated an intrinsic apoptotic pathway in Sp2/0‐Ag14 cells. Supporting this idea, the cytosolic release of the mitochondrial proteins SMAC/DIABLO and cytochrome c (Cyt c) was observed, with an initial limited leakage occurring during the first 30 min of L‐glutamine deprivation, followed by a greater release after 60 min. The latter occurred simultaneously with the translocation of the pro‐apoptotic protein Bax to the mitochondria. Finally, a decline in XIAP levels and the activation of caspases‐3 and ‐9 were observed. Thus, L‐glutamine deprivation of Sp2/0‐Ag14 cells rapidly triggers intracellular events, which target the mitochondria, leading to the cytosolic release of apoptogenic factors, the activation of caspases‐9 and ‐3, and the commitment to the death program. This work introduces the Sp2/0Ag14 hybridoma as a unique model for the study of the molecular events underlying the pro‐survival function of L‐glutamine. © 2004 Wiley‐Liss, Inc.
Balancing neuronal death
Authors: Prunell Giselle F. , Troy Carol M.
Published: August 2004

Although it is apparent that neuronal death must be tightly regulated to ensure the proper development and mature functions of the nervous system, the molecular details of this regulation are not fully understood. In multiple neurodegenerative diseases, there is inappropriate death of cells in the nervous system. A better understanding of how death is regulated in the normal nervous system can provide a framework for determining how this regulation can go awry during neurodegenerative disease. The key executioners of neuronal apoptosis, the caspases, are regulated at several levels. The endogenous inhibitor of apoptosis family of proteins, the IAPs, can suppress caspase activity. In this Mini‐Review, we examine what is known about the function of IAPs in normal neuronal function and in disease. © 2004 Wiley‐Liss, Inc.
The recent Sahel drought is real
Authors: Dai Aiguo , Lamb Peter J. , Trenberth Kevin E. , Hulme Mike , Jones Philip D. , Xie Pingping
Published: August 2004

Using station rainfall data extracted from two comprehensive data sets, we show that large decreasing rainfall trends were widespread in the Sahel (10–20°N and 18°W–20°E) from the late 1950s to the late 1980s. Thereafter, Sahel rainfall has recovered somewhat through 2003, although the drought conditions have not ended in the region. These results confirm the findings of many previous studies. We also found that large multi‐year oscillations appear to be more frequent and extreme after the late 1980s than previously. Analyses of Sahel regional rainfall time series derived from a fixed subset of stations and from all available stations show that the decreasing trend in Sahel rainfall is not an artifact of changing station networks. The rainfall model used by Chappell and Agnew (2004 International Journal of Climatology 24: 547–554) is incorrect and their modelled rainfall time series is totally unrepresentative of Sahel average rainfall. Their conclusion about the Sahel rainfall trends being an artifact of changing station locations is emphatically wrong and their speculative statements about the implications of their results for other studies and other regions of the world are completely unfounded. Copyright © 2004 Royal Meteorological Society
Thermal Characterization of Upper Critical Solution Temperature m‐LLDPE/Poly(ethylene‐ran‐butene) Elastomer Blends
Authors: Li Chaoxu , Kong Qingshang , Zhao Jun , Zhao Delu , Fan Qingrong , Xia Yanzhi
Published: August 2004

Summary: The phase and thermal characteristics of blends consisting of linear low‐density polyethylene (LLDPE) (0.7 mol‐% hexene copolymer) and poly(ethylene‐ran‐butene) (PEB) (26 mol‐% butene copolymer) have been investigated using optical microscopy (OM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). An upper critical solution temperature of 162 °C was exhibited. The addition of PEB not only slowed the overall crystallization rate of LLDPE but also changed the distribution of lamellar thickness or perfection of LLDPE crystals. The equilibrium melting temperature of LLDPE in the blends was reduced and kept relatively constant in the bi‐phase state. The blends showed a single‐stage degradation and an intermediate thermal stability between those of the individual components. It could be attributed to their homogeneous states at degradation temperatures and the similar decomposing mechanisms of two components. The kinetic analysis of thermal degradation also confirmed the above results.

Phase diagram of LLDPE/PEB blends.

magnified image

Phase diagram of LLDPE/PEB blends.
Population Balance Model for Miniemulsion Polymerization, 1
Authors: Sood Ashwini , Awasthi Shailendra K.
Published: August 2004

Summary: Miniemulsion polymerization is a relatively new process that can produce polymer latexes of unusual characteristics. The initial droplet size distribution and the final particle size distribution in miniemulsion polymerization are broad. This has not been addressed by the present models that assume monodisperse droplet size and particle size distributions. A population balance framework for the miniemulsion polymerization that incorporates both the droplet size distribution and the particle size distribution is developed in this work.

Average number of radicals per particle.

image

Average number of radicals per particle.
Characterization of gallotannins and benzophenone derivatives from mango (Mangifera indica L. cv. ‘Tommy Atkins’) peels, pulp and kernels by high‐performance liquid chromatography/electrospray ionization mass spectrometry
Authors: Berardini Nicolai , Carle Reinhold , Schieber Andreas
Published: August 2004

Polyphenolics were extracted from peels, pulp and kernels of mango fruits (Mangifera indica L. cv. ‘Tommy Atkins’) and characterized by high‐performance liquid chromatography/electrospray ionization mass spectrometry. In the peel 18 gallotannins and five benzophenone derivatives were detected which were tentatively identified as galloylated maclurin and iriflophenone glucosides. Twenty‐one and eight gallotannins were found in the kernels and pulp, respectively, whereas no evidence for the presence of benzophenone derivatives was obtained. Gallotannins quantified by the rhodanine assay amounted to 1.4 mg/g dm in the peels (expressed as gallic acid), while only small amounts (0.2 mg/g dm) were found in the pulp. In contrast, mango kernels contained 15.5 mg/g dm and thus proved to be a rich source of gallotannins. Copyright © 2004 John Wiley & Sons, Ltd.
Detection of new radiation‐induced DNA lesions by liquid chromatography coupled to tandem mass spectrometry
Authors: Regulus Peggy , Spessotto Sébastien , Gateau Mathilde , Cadet Jean , Favier Alain , Ravanat Jean‐Luc
Published: August 2004

High‐performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry (HPLC/ESI‐MS/MS) has been used to search for the formation of as yet unidentified radiation‐induced DNA lesions. For that purpose, the characteristic fragmentation of most of 2′‐deoxyribonucleosides that corresponds to the loss of the 2‐deoxyribose moiety (loss of 116 mass units) has been utilized to specifically detect modified nucleosides. Aerated aqueous solutions of DNA were exposed to ionizing radiation, and subsequently DNA was digested to nucleosides with a cocktail of endo‐ and exonucleases. HPLC/ESI‐MS/MS analysis of the resulting 2′‐deoxyribonucleoside mixture allowed us to detect four novel DNA modifications. In a subsequent step, the sensitivity of the tandem mass spectrometer was used to search for the formation of the newly detected lesions in the DNA of γ‐irradiated cells. Thus, one of the four newly detected lesions was found to be significantly generated in cellular DNA upon exposure to ionizing radiation. In addition, the latter lesion was also shown to be present in untreated cells, indicating that the modified nucleoside could be formed endogenously. Copyright © 2004 John Wiley & Sons, Ltd.
Changes in the intellectual structure of strategic management research: a bibliometric study of the Strategic Management Journal, 1980–2000
Authors: Ramos‐Rodríguez Antonio‐Rafael , Ruíz‐Navarro José
Published: August 2004

The aim of this paper is to identify the works that have had the greatest impact on strategic management research and to analyze the changes that have taken place in the intellectual structure of this discipline. The methodology is based on the bibliometric techniques of citation and co‐citation analysis which are applied to all the articles published in the Strategic Management Journal from its first issue in 1980 through 2000. Copyright © 2004 John Wiley & Sons, Ltd.
CEOs who have COOs: contingency analysis of an unexplored structural form
Authors: Hambrick Donald C. , Cannella Albert A.
Published: August 2004

We use contingency theory to examine, for the first time, the incidence and effectiveness of CEO/COO duos. We argue that industry dynamism, extraordinary organizational task demands, and the CEO's own professional limitations will influence the decision to have a COO, as well as its effect on performance. Based on a large 10‐year sample, we find some support for the contingency view in explaining the presence of COOs; we particularly find that CEOs who lack experience in operational activities and in managing the focal firm are relatively likely to have COOs. We find, however, essentially no support for the contingency view in explaining when COOs are most beneficial. Instead, we find strong evidence of a very substantial negative main effect: CEOs who have COOs deliver lower organizational performance than those who do not. Copyright © 2004 John Wiley & Sons, Ltd.
Does country matter?
Authors: Makino Shige , Isobe Takehiko , Chan Christine M.
Published: August 2004

Previous studies have explored the predictors of business unit performance in multiple‐business firms and investigated the extent of the effect of industry, corporate, and business unit on the performance of a business unit. These studies have focused almost exclusively on examining performance differences within a single country, thus treating country effects as external to business unit performance. In contrast, this study focuses on multinational corporations and examines the extent to which country effects explain the variation in the performance of foreign affiliates. Our findings show that country effects are as strong as industry effects, following affiliate effects and corporate effects. Our results also suggest that corporate and affiliate effects tend to be more critical in explaining the variation in foreign affiliate performance in developed countries, whereas country and industry effects are more salient in developing countries. Copyright © 2004 John Wiley & Sons, Ltd.
How many eggs should be laid in one's own nest and others’ in intra‐specific brood parasitism?
Authors: Takasu Fugo
Published: August 2004

Recent field studies have demonstrated that many bird species practice intra‐specific brood parasitism. They lay eggs in the nests of other individuals of the same species, let the foster parents rear their offspring and avoid the cost of parental care. It has been shown that many birds, including starlings, swallows and geese, practice intra‐specific brood parasitism in various forms. Intra‐specific brood parasitism can be viewed in terms of optimal resource allocation: how many eggs should be put in the nests of other individuals under the risk of being parasitized by others. The situation here is a “game”, because the fitness of a parasitic individual depends on how other individuals behave (how many individuals practice parasitism and to what extent). The ecology of intra‐specific brood parasitism has been investigated extensively by field ornithologists recently and it is full of material for modeling population/evolutionary biology. In this paper, I present a simple individual‐based model to challenge the resource allocation problem in intra‐specific brood parasitism. Previous theoretical studies of intra‐specific brood parasitism have been based on ESS or quantitative genetics models, where a population is implicitly assumed to be homogeneous and the distribution form of the trait being studied (the allocation rate or the number of eggs laid parasitically) is inherently monomorphic. This paper aims to explore the evolution of intra‐specific brood parasitism without these restrictions. In the model, an individual is assigned a strategy, an allocation ratio of eggs that are laid parasitically in the nests of other individuals, and the strategy is inherited by offspring either asexually or sexually. Based on the simulation analysis, the evolution of the allocation rate (the extent of intra‐specific brood parasitism) is discussed. The extension of this model to a tractable analytical model is also discussed.
Effect of partial hepatectomy on the formation and elimination of 3‐methyldibenzo(c,g)carbazole and 5,9‐dimethyldibenzo(c,g)carbazole‐DNA adducts in mouse liver
Authors: Szafarz David , Valero Danièle , Perin François , Bornecque Claude
Published: August 2004

Summary— Tritium‐labeled 3‐methyldibenzo(c,g)carbazole and 5,9‐dimethyldibenzo(c,g)‐carbazole, 2 organ‐specific hepatocarcinogens in mice, were given intraperitoneally to partially hepatectomized animals at various times during the first cell division cycle following surgery. The former compound, more potent and cytotoxic, gave more striking results showing that the maximum number of adducts per unit weight of DNA in liver were formed when the carcinogen was given at the beginning of the S phase, which is evidence for the role of DNA replication in the initiation step of carcinogenesis. Elimination of these adducts led after several days to a residual number of lesions which was of the same order whatever the time of carcinogen administration. In the case of 5,9‐dimethyldibenzo‐carbazole there were fewer adducts formed after hepatectomy and their removal was much slower.
Scaffold‐like structures in mouse chromosomes revealed by restriction endonuclease digestion and electron microscopy
Authors: de la Vega Carlos Garcia , López‐Fernández Carmen , Esponda Pedro , Campos Asuncion , Goyanes Vicente , Gosálvez Jaime
Published: August 2004

Summary— A scaffold‐like structure is observed under the electron microscope when mouse chromosomes are digested with the restriction endonuclease Hae III. This structure, located in the inner part of chromatids, may correspond to those fragments of chromatin loops anchored to the chromosome scaffold and is obtained when chromosomes are treated either in suspension or attached to grids. The width of the structure is correlated with the extent of digestion in chromosomes treated in suspension. Those treated on grids show this structure whenever chromatids do not collapse. These results agree with the model of chromosome organization based on a non‐histone protein scaffold.
The role of the vimentin intermediate filaments in rat 3Y1 cells elucidated by immunoelectron microscopy and computer‐graphic reconstruction
Authors: Katsumoto Tetsuo , Mitsushima Akira , Kurimura Takashi
Published: August 2004

Summary— The three‐dimensional arrangement of vimentin intermediate filaments (IF) was studied in 3Y1, rat fibroblastic cell line, to elucidate its biological role in the cell. While actin filaments were observed exclusively in the superficial part of the cell, vimentin IF were found to be abundantly present in the inside of the cell where microtubules were occasionally discovered. By whole‐mount immunoelectron microscopy and computer‐graphic reconstruction of serial thin sections, it was observed in more detail that vimentin IF are located very close to the nucleus, endoplasmic reticulum, and mitochondria. Vimentin IF were observed to be attached to these organelles laterally or terminally. Thus, we can reasonably assume that vimentin IF are major cytoskeletal structures deep inside the cell and that they play an important role in supporting the location of the organelles. This is the first report which has visualized the three‐dimensional relationship between vimentin IF and the organelles of the cell.
Epidermal‐dermal and fibronectin cell‐interactions during fish scale regeneration: immunofluorescence and TEM studies
Authors: Sire Jean‐Yves , Boulekbache Habib , Joly Claire
Published: August 2004

Summary— Fibronectin (FN) immunolocalization and ultrastructural observations of epidermal‐dermal cell interactions during skin regeneration of the cichlid fish Hemichromis bimaculatus after scale removal were carried out for a healing period of 48 h. On control samples after scale removal, FN was localized on the surface of a thin cellular sheet, the scale‐pocket lining (SPL), separating the dermis from the scale‐associated cells. A layer of extracellular matrix, constituting a basement membrane, was observed on the SPL surface. Study of wound healing showed that in less than 1 h epithelial cells spread rapidly over the undamaged SPL surface on which FN was still present after the scale was removed. It appeared that this FN can be damaged or lost if the area is exposed to the exterior water for more than one hour. When epithelial continuity was re‐established, an epithelial‐SPL space was formed and was progressively filled by an electron‐dense extracellular matrix. No basement membrane was defined until both tissues were separated by dermal cells about 30 h after the wound was inflicted. FN is detected in the epithelial‐SPL interface from 12 h to 30 h after scale removal. Therefore, in normal skin, specific localization of FN in the interface between the scale‐associated cells and the outer surface of the SPL cells can be implicated in the attachment between the scale and the SPL surface favoring a flexibility of scale movement during swimming. In addition, FN could play an important role as a major extracellular matrix protein during wound‐healing after scale removal.
Isolation and characterization of a RNA‐virus like particle from Candida curvata
Authors: Matte Oriane , Chabalier Catherine , Ratomahenina Robert , Bossy Jean‐Pierre , Galzy Pierre
Published: August 2004

Summary— A virus‐like particle (VLP) of 35 nm diameter has been isolated from the lipolytic yeast Candida curvata. The VLP contains a linear, double stranded RNA molecule of 1.55 μm in length.
In situ separation of nucleolar components by hypotonic treatment of cells
Authors: Hozák Pavel , Zatsepina Olga V. , Likovský Zbyněk
Published: August 2004

Summary— The main features of the reaction of nucleolar components to a simple hypotonic shock are described. In place of nucleoli, only fibrillar complexes remain. Such preservation provides another morphological proof of the hypothesis of fibrillar complexes as morphological‐functional units in active nucleoli. Moreover, this method can become a good tool for further study of nucleolus‐organizing regions.
Architecture of the fluid cellulosic arrays in the epidermis of the quince seed
Authors: Abeysekera Rukmal M. , Willison J.H. Martin
Published: August 2004

Summary— Using thin‐sectioning for electron microscopy, including the careful examination of a long series of sections which contained several complete cells, we describe the form of the contents of the unusually enlarged distal periplasmic space in the epidermis of the seeds of Cydonia oblonga. The major feature is a large stack of cellulosic material arranged helicoidally, which previous work has indicated is fluid and similar to a cholesteric liquid crystal. This stack has a serrated margin, which is interpreted as indicating a surface shaped like that of a screw or a concertina. The overall shape based upon artistic reconstructions from serial sect?? shows great ?? variability, due in part to the limits set by the enclosing cell walls. This together with observations of variation in helicoidal pitch and of helicoidal arc reversal, indicates that the crystals are highly plastic in form. It is suggested that the form is determined by a combination of intrinsic and extrinsic factors. Not all microfibrils in the periplasmic pocket are arranged helicoidally, and it is argued that the coexistence of helicoidal and non helicoidal microfibrillar arrays indicates that a gradient of an agent which controls cellulose microfibrillar architecture is present. This may indicate that cell wall architecture can similarly be determined by subtle regulation of agents which control helicoidal pitch.
High levels of HMG1‐2 protein expression in the cytoplasm and nucleus of hydrocortisone sensitive amphibian thymocytes
Authors: Guillet Franc¸oise , Tournefier Annick , Denoulet Philippe , Capony Jean‐Paul , Kerfourn Fabienne , Charlemagne Jacques
Published: August 2004

Summary— A major 26 kDa protein was identified in the cytoplasmic and nuclear compartments of axolotl thymocytes. A polyclonal antiserum was produced against the denatured form of this protein. High levels of 26 kDa were expressed by hydrocortisonesensitive lymphocytes which represent a major thymocyte subpopulation in young animals. However, no further expression of the 26 kDa protein was observed in involuted thymus of adult animals nor in thymus of young artificially metamorphosed axolotls. The 26 kDa was never expressed by splenic and blood peripheral lymphocytes at any stage of development. Partial N‐terminal amino acid sequence and amino acid composition demonstrate that the 26 kDa polypeptide is strongly homologous to HMGI‐2 proteins, the most abundant members of the high mobility group (HMG) non‐histone chromosomal proteins. HMG1‐2 are thought to be involved in the organization of chromatin structure, as well as in the stability, replication and transcription of DNA. It was confirmed that the 26 kDa axolotl polypeptide is recognized by a well characterized rabbit antiserum to rat HMG1‐2 proteins.
Quantitative immunocytochemical studies of endogenous albumin in rat aortic endothelial and mesothelial cells
Authors: London˜o Irene , Bendayan Moise
Published: August 2004

Summary— Endogenous albumin was revealed over cellular structures of rat ascendent aorta endothelia and mesothelium, with high resolution and specificity, by applying the protein A‐gold immunocytochemical approach. This approach allows albumin distribution to be studied under steady‐state conditions. The cellular layers evaluated were the aortic endothelium, the capillary endothelium (vasa vasorum), and the mesothelium externally lining the aorta at this level. Gold particles, revealing albumin antigenic sites, were preferentially located over plasmalemmal vesicles and intercellular clefts of endothelial and mesothelial cells, though with different labeling intensities. The interstitial space was also labeled. Morphometrical evaluation of plasmalemmal vesicles demonstrated a higher surface density for these structures in capillary endothelial cells (12%) compared with those in aortic endothelial (5%) and mesothelial cells (2%). Quantitation of gold labeling intensities over these structures revealed a higher labeling over plasmalemmal vesicles of capillary endothelium than over those of aortic endothelium and mesothelium. This result, together with the higher surface density of plasmalemmal vesicles found in capillary endothelium, suggest an important role of these structures in the transendothelial passage of endogenous albumin, particularly for capillary endothelium. On the other hand, labeling densities over mesothelial clefts were found to be higher than those of capillary and aortic endothelia. Results from this study concur with the proposal of a differential passage of albumin according to the cell lining considered, and suggest a role for mesothelial intercellular clefts in contributing to the presence of albumin in interstitial spaces.
SIMS microscopy in the biomedical field
Authors: Fragu Philippe , Briançon Colette , Fourré Catherine , Clerc Jérôme , Casiraghi Odile , Jeusset Josette , Omri Frédérique , Halpern Sylvain
Published: August 2004

Summary—

We attempted to indicate the requirements for biomedical applications of SIMS microscopy. Sample preparation methodology should preserve both the structural and the chemical integrity of the tissue. Furthermore, it is often necessary to correlate ionic and light microscope images. This implies a common methodological approach to sample preparation for both microscopes. The use of low or high mass resolution depends on the elements studied and their concentrations. To improve the acquisition and processing of images, digital imaging systems have to be designed and require both ionic and optical image superimposition. However, the images do not accurately reflect element concentration; a relative quantitative approach is possible by measuring secondary ion beam intensity. Using an internal reference element (carbon) and standard curves the results are expressed in μg/mg of tissue. Despite their limited lateral resolution (0.5 μm) the actual SIMS microscopes are very suitable for the resolution of biomedical problems posed by action modes and drug localization in human pathology. SIMS microscopy should provide a new tool for metabolic radiotherapy. by facilitating dose evaluation. The advent of high lateral resolution SIMS imaging (< 0.1 μm) should open up new fields in biomedical investigation.
Preservation of the diffusible cations for SIMS microscopy. I. A problem related to the state of water in the cell
Authors: Mentré Pascale
Published: August 2004

Summary—

The notion of diffusible ions is reviewed in the light of recent knowledge on the stage of water in biological matrices. It appears that ion distributions would be little affected as long as water‐macromolecular equilibrium is maintained, but they risk to be significantly modified during dehydration, because the transformation of bound water into highly solvating free water can produce ion displacements. In addition, differently hydrated areas may undergo unequal volume variations. The principal modes of preparing material for SIMS (secondary ion mass spectrometry) microscopy are envisaged from this viewpoint.
Significance of SIMS microscopy for the radioiodine detection in animal and human thyroid tissue*
Authors: Briançon Colette , Jeusset Josette , Francese Cecilia , Omri Frédérique , Halpern Sylvain , Fragu Philippe
Published: August 2004

Summary—

We defined the SIMS conditions for radioiodine detection in animal and man thyroid follicles, in tissue sections (3 μm) chemically fixed and resin embedded. Two radioisotopes were tested: 125I and 129I, of high (14 mCi 125I μg−1) and low specific activity (1.07 10−6 mCi 129I μg−1). In animal study, Wistar rats fed a normal iodine diet (10 μg 127I day−1) were injected ip 24 h before sacrifice either with 125I (7 10−3 μg) or with 129I at a dose identical to iodine diet (10 μg) or 3 times higher (30 μg). No SIMS signal of 125I was obtained in vivo due to its too low concentration, while radioiodine distribution was evidenced with both doses of 129I. Local concentration of previously stored 127I in follicular lumen was not modified, when compared to control (4.14 ± 0.03 μg/mg, m ± SE), by 125I or 129I at a dose of 10 μg, but was nearly doubled with 129I at a dose of 30 μg, proof of a pharmacological effect on thyroid iodine regulation. In human study 129I was excluded due to its long half‐life (1.6 107 years), and 125I was tested only in vitro on two surgical specimens of normal perinodular thyroid tissue maintained in mini‐organ culture for 48 h in presence of 100 μCi/ml of 125I. The 125I was detectable, its concentration was 1000‐fold higher than that of 127I (1.5 ± 0.004 μg/mg). For both in vivo and in vitro studies, a positive correlation exists between newly organified radioiodine (125I or 129I) and previously stored iodine (127I). In conclusion, the radioisotope 129I used at a dose of 10 μg is well adapted for SIMS detection in vivo of thyroid exchangeable iodine, but only in animal, while 125I isotope is especially adapted for in vitro study in man.