bluuebunny/crossref_metadata_2025 huggingface dataset:
The development of boys' preferential pleasure in physical aggression
Authors: Benenson Joyce F. , Carder Hassina P. , Geib‐Cole Sarah J.
Published: August 2007

A large body of literature on physical aggression focuses on its maladaptive nature and causes. The current study of 335 children (209 boys, 126 girls), aged 4‐, 5‐, 6‐, and 9‐years, examined a different facet of harmful physical aggression–the development of the pleasure it provides to boys. Two samples of children were included, first 89 boys, then an additional 120 boys and 126 girls. For the first two free response measures, all 209 boys and 126 girls were asked to describe how they played with their three favorite toys and their three favorite playmates, and these descriptions were coded for the presence of physical aggression. Twelve additional structured measures were administered to the second sample of 120 boys and 126 girls. These children were asked to rate how much they enjoyed enacting and viewing on television physical aggression, non‐physically aggressive male sex‐typed roles, and ambiguously sex‐typed roles. Results demonstrated that approximately 50% of boys at all four age levels (and less than 10% of girls) reported that at least one of their three favorite toys was used for inflicting harm through physical aggression on an animate being. Further, with increasing age, boys rated physical aggression in play activities and on television as more enjoyable than alternative male sex‐typed play and television content. Results suggest that advancing understanding of the development of physical aggression requires acknowledging the pleasure it provides to males. Aggr. Behav. 34:154–166, 2008. © 2007 Wiley‐Liss, Inc.
Click Chemistry: Versatility and Control in the Hands of Materials Scientists
Authors: Nandivada H. , Jiang X. , Lahann J.
Published: August 2007

The increasing need for materials with tightly controlled structures will continue to fuel the induction of synthetic organic concepts into materials science. One powerful example is the embracement of “click chemistry” by the materials science community. Because of their high selectivity, near‐perfect reliability, high yields, and exceptional tolerance towards a wide range of functional groups and reaction conditions click reactions have recently attracted increased attention, specifically for use in polymer synthesis as well as for the modification of surfaces and nanometer‐ and mesoscale structures. As outlined in this Review article, click chemistry, such as the CuI‐catalyzed Huisgen 1,3‐dipolar cycloaddition and the Diels–Alder reaction, presents a synthetic concept that lends itself superbly to the controlled preparation of multifunctional materials.
Regional differences in the genetic variability of Finno‐Ugric speaking Komi populations
Authors: Khrunin Andrey , Verbenko Dmitry , Nikitina Kseniya , Limborska Svetlana
Published: August 2007

The Komi (Komi‐Zyryan) people are one of the most numerous ethnic groups belonging to the Finno‐Ugric linguistic community. They occupy an extensive territory in north Russia to the west of the Ural Mountains, in the northeast of the East European Plain. This is an area of long‐term interactions between Europeans and North Asians. Genetic variability was evaluated in two geographically distinct populations, the Izhemski and Priluzski Komi. We searched for polymorphisms of the TP53 gene (a 16‐bp duplication in intron 3 and three RFLPs: for Bsh1236I at codon 72, for MspI in intron 6, and for BamHI in the 3′ flanking region) and for variable number tandem repeat (VNTR) polymorphisms of locus D1S80 and of the 3′ untranslated region of the gene for apolipoprotein B (ApoB). Some data from our previous studies of TP53, 3′ApoB, and D1S80 variability were involved in the comparison of Komi with other Eastern European populations. Multidimensional scaling analysis of genetic distances was used for the evaluation of genetic relationships between populations. The results revealed some affinity between Priluzski Komi and Eastern Slavonic populations, and significant segregation of Izhemski Komi from other ethnic groups studied. The unique genetic features of Izhemski Komi may have been determined by their ethnogenesis or the pressure of environmental factors, such as special nutrition and adaptation to extreme climatic conditions. Am. J. Hum. Biol., 2007. © 2007 Wiley‐Liss, Inc.
Effect of fiber surface modification on the mechanical properties of sisal fiber‐reinforced benzoxazine/epoxy composites based on aliphatic diamine benzoxazine
Authors: Tragoonwichian Suchada , Yanumet Nantaya , Ishida Hatsuo
Published: August 2007

Sisal fibers were incorporated into a mixture of benzoxazine and bisphenol A type epoxy resins to form a unidirectionally reinforced composite. Surface modifications of the sisal fibers were carried out with sodium hydroxide, γ‐aminopropyltrimethoxysilane, and γ‐glycidoxypropyltrimethoxysilane. The surface treatments led to changes in the morphology, chemical groups, and hydrophilicity of the fibers. The effect of the fiber surface treatments on the fiber–matrix interfacial adhesion and mechanical properties of the composites were also studied. The results showed that surface treatments with sodium hydroxide and a silane coupling agent led to improved fiber–matrix adhesion; this could be seen in the scanning electron micrographs of the fractured surfaces from mechanical testing and the reduction in the impact strength of the composites made from treated fibers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Molecular orientation of extruded PET/LCP blend films. II. X‐ray pole figures
Authors: Branciforti Marcia C. , Silva Lucineide B. , Machado Rogerio , Bretas Rosario E. S.
Published: August 2007

The crystalline uniaxial molecular orientation of two liquid crystalline polymers (LCPs), Vectra®A950, and Rodrun®LC5000, blended with poly(ethylene terephthalate) (PET) was obtained from wide angle X‐ray pole figures. The blends films were produced by extrusion using a twin screw extruder with a slit die. The molecular orientation was evaluated along the transverse section of the films and as a function of the blends composition. The influence of a compatibilizer agent on the LCPs orientation was also analyzed. It was found that the orientation of both LCPs in the pure LCP films was high, highest in the draw direction but variable along the transverse section of the extruded films; in this last case, it was higher at the position where the shear rate was maximum. However, a drastic orientation decrease in both LCP's phases was observed in the films made of PET/LCPs blends. The maximum orientation effects were observed for the blend with 5 wt % of LCP content and also at the position where the shear rate was the highest. The Vectra®A950 LCP, as a pure material and in the blend with PET, orient more effectively than the Rodrun®LC5000 LCP in the films produced at the same processing conditions. The results showed that the use of a compatibilizer agent decreased the LCP orientation and were in accordance with previous studies using polarized infrared spectroscopy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Quiescent crystallization of natural fibers–polypropylene composites
Authors: Somnuk Usa , Eder Gerhard , Phinyocheep Pranee , Suppakarn Nitinat , Sutapun Wimonlak , Ruksakulpiwat Yupaporn
Published: August 2007

The effect of natural fibers (vetiver grass and rossells) on quiescent crystallization of polypropylene (PP) composites was analyzed in this study. Also, equilibrium melting temperature (T) of the composites was elucidated. Natural fiber‐PP composites showed lower T when compared to neat PP. Thermal analysis was performed via differential scanning calorimeter to study the crystallization kinetics. Natural fiber‐PP composites exhibited higher rate of crystallization than that of neat PP. Furthermore, spherulitic growth rate and transcrystallinity of the composites were investigated under a polarized light optical microscope. It was found that the growth rates of the composites were lower than that of neat PP. The spherulitic growth rates combined with the crystallization rates were used to calculate number of effective nuclei. It was shown that the number of effective nuclei of the composites was higher than that of neat PP. This suggested that natural fibers could act as a nucleating agent in the composite. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Georadar data collection, anomaly shape and archaeological interpretation – a case study from central Italy
Authors: Orlando Luciana
Published: August 2007

Georadar data were acquired on an area 50 m long (X direction) by 30 m wide (Y direction), with profiles respectively 0.5 and 1 m apart. The data were processed with the goal of increasing the signal to noise ratio. Stacks of two and four samplings in time were applied in order to enhance the reflectivity of weak anomalies on time slices. The time slices were also used to analyse the effects on image quality of the distance between profiles and the profile direction with respect to anomaly location. The study shows that time slices obtained from profiles acquired 1 m apart detect the same anomalies acquired with profiles 0.5 m apart but with incorrect geometries.

The interpretation was performed on both vertical profiles and time slices. The most meaningful anomalies have been mapped and grouped into three types according to archaeological significance: surficial anomalies, which are easily reached in the preliminary excavation trials, and deep, separate single and complex anomalies, the latter being formed by several anomalies.

The magnetic gradient was sampled on a 0.5 × 0.5 m grid, and values of more than ±500 nT were detected. The western zone is characterized by several chaotic magnetic anomalies, whereas the rest of the area has a few anomalies of dipole shape.

The joint interpretation of the georadar and magnetic data reveals a good overlap of magnetic and georadar anomalies in the west zone. They are surficial and have been correlated to earthenware remains, probably medieval in age. The anomalies detected by georadar and magnetic methods in the centre and eastern zones do not, in most of the cases, overlap, so we presume that the two methods detected different features. The joint interpretation of the georadar and magnetic data has allowed the mapping of the main archaeological anomalies, thus providing a useful tool for planning the archaeological excavation. Copyright © 2007 John Wiley & Sons, Ltd.
Hagfish embryos again—the end of a long drought
Authors: Holland Nicholas D.
Published: August 2007

Hagfishes have long held a key place in discussions of early vertebrate evolution. Frustratingly, one basis for such discussions—namely hagfish embryology—is very incompletely known, because the embryos of these animals are notoriously difficult to obtain.1,2 Fortunately, a recent publication on a Far Eastern hagfish3 describes a workable procedure for obtaining embryos and then uses this precious material to show that the hagfish neural crest arises by cell delamination as in other vertebrates—and not by epithelial outpouchings from the wall of the neural tube as previously claimed.4 Importantly, because hagfish embryos should now be available on a regular basis, the way is open for additional morphological and developmental genetic investigations to help evaluate existing evolutionary scenarios and perhaps suggest new ones. BioEssays 29:833–836, 2007. © 2007 Wiley Periodicals, Inc.
Biochemistry and molecular biology of Arabidopsis–aphid interactions
Authors: de Vos Martin , Kim Jae Hak , Jander Georg
Published: August 2007

To ensure their survival in natural habitats, plants must recognize and respond to a wide variety of insect herbivores. Aphids and other Hemiptera pose a particular challenge, because they cause relatively little direct tissue damage when inserting their slender stylets intercellularly to feed from the phloem sieve elements. Plant responses to this unusual feeding strategy almost certainly include recognition of aphid salivary components and the induction of phloem‐specific defenses. Due to the excellent genetic and genomic resources that are available for Arabidopsis thaliana (Arabidopsis), this plant was chosen as a model system to study the metabolic and transcriptional responses to infestation by two aphids, Myzus persicae (green peach aphid, a broad generalist) and Brevicoryne brassicae (cabbage aphid, a crucifer‐feeding specialist). Future research on Arabidopsis–aphid interactions will lead to the identification of aphid‐specific elicitors, components of the defense‐signaling pathway, and additional metabolic responses that are induced by aphid infestation. BioEssays 29:871–883, 2007. © 2007 Wiley Periodicals, Inc.
Evolution of global regulatory networks during a long‐term experiment withEscherichia coli
Authors: Philippe Nadège , Crozat Estelle , Lenski Richard E. , Schneider Dominique
Published: August 2007

Evolution has shaped all living organisms on Earth, although many details of this process are shrouded in time. However, it is possible to see, with one's own eyes, evolution as it happens by performing experiments in defined laboratory conditions with microbes that have suitably fast generations. The longest‐running microbial evolution experiment was started in 1988, at which time twelve populations were founded by the same strain ofEscherichia coli. Since then, the populations have been serially propagated and have evolved for tens of thousands of generations in the same environment. The populations show numerous parallel phenotypic changes, and such parallelism is a hallmark of adaptive evolution. Many genetic targets of natural selection have been identified, revealing a high level of genetic parallelism as well. Beneficial mutations affect all levels of gene regulation in the cells including individual genes and operons all the way to global regulatory networks. Of particular interest, two highly interconnected networks—governing DNA superhelicity and the stringent response—have been demonstrated to be deeply involved in the phenotypic and genetic adaptation of these experimental populations. BioEssays 29:846–860, 2007. © 2007 Wiley Periodicals, Inc.
The underestimated potential of the immune system in prevention of Alzheimer's disease pathology
Authors: Mohajeri M. Hasan
Published: August 2007

Genetic and environmental factors leading to Alzheimer's disease (AD) converge in a pathogenic pathway that leads to the accumulation of mis‐folded amyloid peptide (Aβ) in the brain. Removal of Aβ from the brain has thus been the focus of academic and industrial research in the last decade. The concept of immunization therapy could be proven in animal models mimicking amyloid pathology but a multicenter clinical trial in which AD patients were vaccinated with aggregated Aβ has resulted in somewhat unanticipated and partially conflicting results. The occurrence of meningoencephalitis in 6% of vaccinated individuals forced the discontinuation of the clinical study, preventing the generation of sufficient data for an unequivocal statement about the effectiveness of such a therapy approach. This study, however, clearly showed that vaccination induced the production of antibodies against Aβ in some immunized patients. Moreover, circulating anti‐Aβ antibodies are found in healthy humans suggesting a protective role of such physiological antibodies. Nonetheless, the physiological role of the immune system in preventing AD is not fully understood. This article summarizes crucial animal and clinical data underscoring the potential of the immune system for AD treatment. BioEssays 29:927–932, 2007. © 2007 Wiley Periodicals, Inc.
Changing structures: Necessary but not sufficient
Authors: Skinner Kate , Bell Lorna
Published: August 2007

Moves are afoot across the UK to change the mechanisms for managing local inter‐agency child protection policy and practice. This is being achieved through the development of Safeguarding Boards in England and Wales and guidance on Child Protection Committees that took effect from August 2005 in Scotland. Following our review of one Scottish Child Protection Committee (the SCPC), we are concerned that these changes focus almost exclusively on structure and pay scant attention to process and relationships.

The study we undertook was an in‐depth evaluation of the functioning of the SCPC and used a range of qualitative methods. The main findings were that the size of the committee, its coverage of three local authority areas, and its patterns of working meant that some aspects of its work were highly developed and effective, such as the guidelines and multi‐agency training, while others, such as links with practice and the management of information systems, were poor.

Considering these findings in the light of systems theory suggests that improving the effectiveness of child protection committees, and similar bodies, may need to be based on greater attention being paid to issues of authority, trust and negotiation among their members. Copyright © 2007 John Wiley & Sons, Ltd.
Myo1 localizes to phagosomes, some of which traffic to the nucleus in a Myo1‐dependent manner in Tetrahymena thermophila
Authors: Hosein Roland E. , Gavin R. H.
Published: August 2007

Myo1 is one of 13 myosins in Tetrahymena thermophila. Initially, twelve of the myosins in Tetrahymena were assigned to Class XX in the myosin superfamily but recently re‐assigned to a subclass within Class XIV. In a previous study, we reported that genomic knockout of MYO1 affected phagocytosis and macronuclear amitosis. These two phenotypes have appeared disparate because a possible mechanism linking phagocytosis and amitosis was unknown. In the present study, Myo1 localization was investigated in order to further link machinery for phagocytosis and amitosis. Antibodies directed against the Myo1 motor domain detected an immunospecific polypeptide at 175–180 kDa on immunoblots of wild‐type proteins. The 175–180 kDa polypeptide was not detected on immunoblots of proteins from the knockout strain. For immunofluorescence microscopy, cells were allowed to internalize fluorescent beads as markers for phagosomes. In wild‐type cells, anti‐Myo1 and anti‐actin antibodies co‐localized to the periphery of phagosomes and the macronucleus. In the MYO1‐knockout strain only background fluorescence was observed with anti‐Myo1 antibody. Confocal x–z series through macronuclei revealed fluorescent beads within the nucleoplasm. Statistical analysis showed a significant difference between the mean distributions of fluorescent beads in the nucleoplasm of wild‐type and MYO1‐knockout cells. A fluorescent dye was used to label plasma membrane in living cells. Dye‐labeled vacuoles trafficked to the macronucleus. Trafficking of phagosomes to the macronucleus in a myosin‐dependent manner is a novel finding and a possible mechanism for targeting myosin and actin to the nucleus. Cell Motil. Cytoskeleton, 2007. © 2007 Wiley‐Liss, Inc.
Factors affecting consumer use of the Internet for information search
Authors: Jepsen Anna Lund
Published: August 2007

The Internet opens new opportunities for conducting pre-purchase information search. Lower search costs have been found to affect use of the Internet for this purpose. Benefits in terms of the large amounts of information available and freedom from physical contact with sales staff have also been found to affect the use of the Internet for information search positively. In this paper, low costs and benefits are put together in a model. The model was tested by means of structural equation modeling on a sample of Danish Internet users ( n = 233). The main result is that the amount of Internet use affects use of the Internet for pre-purchase information search more than perceived low search costs and perceived availability of information. Further, the test of the model did not support that pleasure in shopping and a preference for personal contact to sales staff affect the use of the Internet for information search.
Consequences of Web-based service quality: Uncovering a multi-faceted chain of effects
Authors: Fassnacht Martin , Köse Ibrahim
Published: August 2007

Evidence from traditional service settings shows that service quality is a major driver of customer satisfaction, trust, and loyalty, which ultimately lead to profitability. Regarding business on the Internet, many argue that trust and loyalty become even more important for long-term success. But does quality play the same influential role in the context of Web-based services, where it is said that price is king and competitors just one click away? In the present study, the authors develop a structural equation model that links Web-based service quality to a broad set of consequences.The model is tested with a large sample drawn from three different Web-based service domains. The results provide insights into the mechanisms leading from Web-based service quality to outcome variables. Specifically, they point to a multifaceted chain of effects, with trust playing a key mediating role.
Adaptive experimentation in interactive marketing: The case of viral marketing at Plaxo
Authors: Kalyanam Kirthi , McIntyre Shelby , Masonis J. Todd
Published: August 2007

This case study shows how interactive marketing campaigns can be systematically fine-tuned and made more productive through adaptive experimentation. It details the use of adaptive experimentation in a viral marketing campaign at Plaxo, Inc., a company that provides Internet-based updating of personal contact information. The experiences of Plaxo highlight that even for a product that is amenable to viral marketing, growth is not guaranteed. To achieve a desired level of growth, Plaxo identified the product features that contributed to greater adoption conversion of recipients of its marketing message and improved them through continuous experimentation. To overcome potential negative side effects of aggressive viral growth, the company used a carefully crafted feedback loop via internet alert services that tapped into the blogging community. This practice allowed management to better understand negative perceptions of the product and take timely corrective actions.
Adult bone marrow–derived stem cells for organ regeneration and repair
Authors: Tögel Florian , Westenfelder Christof
Published: August 2007

Stem cells have been recognized as a potential tool for the development of innovative therapeutic strategies. There are in general two types of stem cells, embryonic and adult stem cells. While embryonic stem cell therapy has been riddled with problems of allogeneic rejection and ethical concerns, adult stem cells have long been used in the treatment of hematological malignancies. With the recognition of additional, potentially therapeutic characteristics, bone marrow–derived stem cells have become a tool in regenerative medicine. The bone marrow is an ideal source of stem cells because it is easily accessible and harbors two types of stem cells. Hematopoietic stem cells give rise to all blood cell types and have been shown to exhibit plasticity, while multipotent marrow stromal cells are the source of osteocytes, chondrocytes, and fat cells and have been shown to support and generate a large number of different cell types. This review describes the general characteristics of these stem cell populations and their current and potential future applications in regenerative medicine. Developmental Dynamics 236:3321–3331, 2007. © 2007 Wiley‐Liss, Inc.
Wnt6 controls amniote neural crest induction through the non‐canonical signaling pathway
Authors: Schmidt Corina , McGonnell Imelda M. , Allen Steve , Otto Anthony , Patel Ketan
Published: August 2007

The neural crest is a multipotent embryonic cell population that arises from neural ectoderm and forms derivatives essential for vertebrate function. Neural crest induction requires an ectodermal signal, thought to be a Wnt ligand, but the identity of the Wnt that performs this function in amniotes is unknown. Here, we demonstrate that Wnt6, derived from the ectoderm, is necessary for chick neural crest induction. Crucially, we also show that Wnt6 acts through the non‐canonical pathway and not the beta‐catenin–dependant pathway. Surprisingly, we found that canonical Wnt signaling inhibited neural crest production in the chick embryo. In light of studies in anamniotes demonstrating that canonical Wnt signaling induces neural crest, these results indicate a significant and novel change in the mechanism of neural crest induction during vertebrate evolution. These data also highlight a key role for noncanonical Wnt signaling in cell type specification from a stem population during development. Developmental Dynamics 236:2502–2511, 2007. © 2007 Wiley‐Liss, Inc.
Drosophila odz gene is required for multiple cell types in the compound retina
Authors: Kinel‐Tahan Yael , Weiss Hanna , Dgany Orly , Levine Anna , Wides Ron
Published: August 2007

The Drosophila melanogaster pair‐rule gene odz (odd Oz, or Ten‐m) is expressed in distinct patterns in the larval eye imaginal disc. Its earliest eye expression occurs in ommatidial precursors starting from the posterior edge of the morphogenetic furrow. Loss of function of odz activity leads to visible light photoreceptor loss; R7 photoreceptor loss; ommatidial size, shape, and rotation defects; ommatidial disorder and fusions; interommatidial bristle defects; and ommatidial lens defects. The same effects are seen in odz eye mitotic clones, in odz–Ten‐a transheterozygous combinations, and in eyes expressing an Odz‐Dominant Negative transgene (Odz‐DN). Effects of the same strength are also seen when the Odz‐DN transgene is driven only in regions of scabrous expression, which overlaps the four columns of Odz expression clusters behind the furrow. Small odz mitotic clones suggest an odz role in cell proliferation or survival. Senseless is expressed in odz mutant clones, in a fairly ordered manner, indicating that Odz acts downstream of R8 specification. Disorder within each ommatidium in odz clones is accompanied by some loss of R7 precursors and visible photoreceptor precursor order. Developmental Dynamics 236:2541–2554, 2007. © 2007 Wiley‐Liss, Inc.
Hox patterning of the vertebrate axial skeleton
Authors: Wellik Deneen M.
Published: August 2007

The axial skeleton in all vertebrates is composed of similar components that extend from anterior to posterior along the body axis: the occipital skull bones and cervical, thoracic, lumbar, sacral, and caudal vertebrae. Despite significant changes in the number and size of these elements during evolution, the basic character of these anatomical elements, as well as the order in which they appear in vertebrate skeletons, have remained remarkably similar. Through extensive expression analyses, classic morphological perturbation experiments in chicken and targeted loss‐of‐function analyses in mice, Hox genes have proven to be critical regulators in the establishment of axial skeleton morphology. The convergence of these studies to date allows an emerging understanding of Hox gene function in patterning the vertebrate axial skeleton. This review summarizes genetic and embryologic findings regarding the role of Hox genes in establishing axial morphology and how these combined results impact our current understanding of the vertebrate Hox code. Developmental Dynamics 236:2454–2463, 2007. © 2007 Wiley‐Liss, Inc.
Abnormal venous and arterial patterning in chordin mutants
Authors: Délot Emmanuèle C. , Shneyder Natalya , Zhang Hanwei , Bachiller Daniel
Published: August 2007

Classic dye injection methods yielded amazingly detailed images of normal and pathological development of the cardiovascular system. However, because these methods rely on the beating heart of diffuse the dyes, the vessels visualized have been limited to the arterial tree, and our knowledge of vein development is lagging. In order to solve this problem, we injected pigmented methylsalicylate resins in mouse embryos after they were fixed and made transparent. This new technique allowed us to image the venous system and prompted the discovery of multiple venous anomalies in Chord−/− mutant mice. Genetic inactivation of Chordin, an inhibitor of the Bone Morphogenetic Protein signaling pathway, results in neural crest defects affecting heart and neck organs, as seen in DiGeorge syndrome patients. Injection into the descending aorta of Chrd−/− mutants demonstrated how a very severe early phenotype of the aortic arches develops into persistent truncus arteriosus. In addition, injection into the atrium revealed several patterning defects of the anterior cardinal veins and their tributaries, including absence of segments, looping and midline defects. The signals that govern the development of the individual cephalic veins are unknown, but our results show that the Bone Morphogenetic Protein pathway is necessary for the process. Developmental Dynamics 236:2586–2593, 2007. © 2007 Wiley‐Liss, Inc.
A New Pentadentate Ligand Forms Both a Di‐ and a Mononuclear MnII Complex: Electrochemical, Spectroscopic and Superoxide Dismutase Activity Studies
Authors: Cisnetti Federico , Lefèvre Anne‐Sophie , Guillot Régis , Lambert François , Blain Guillaume , Anxolabéhère‐Mallart Elodie , Policar Clotilde
Published: August 2007

The X‐ray crystal structure of the dinuclear complex[1(PF6)2] derived from a new ligand bearing both imidazole and phenolato moieties, namely N‐(2‐hydroxybenzyl)‐N,N′‐bis[2‐(N‐methylimidazolyl)methyl]ethane‐1,2‐diamine (LH), is described and its properties in organic solvent (CH3CN) investigated (EPR, electrochemistry). [1(PF6)2] is shown to be a mononuclear MnII species in aqueous solution and displays an efficient SOD‐like activity, as measured by the McCord–Fridovich assay performed both in conventional phosphate buffer and in a noncoordinating buffer (PIPES). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Synthesis, Characterization, and Photoluminescence Properties of In2O3 Nanocrystals Encapsulated by Carbon Vesicles and Neat In2O3 Nanocrystals Generated by the RAPET Technique
Authors: George Pani P. , Gedanken Aharon
Published: August 2007

We report the synthesis of micron‐sized vesicles of carbon encapsulating In2O3 nanocrystals, as well as neat In2O3 nanocrystals. The thermal decomposition of In(acetate)3 was carried out at 800 °C in air. This reaction was carried out under the autogenic pressure of indium acetate. The synthesized products were systematically characterized by X‐ray powder diffraction, scanning electron microscopy, and transmission electron microscopy. Carbon microvesicles, with an average diameter of 5 μm, encapsulated several nanometric‐sized In2O3 nanocrystals, as evidenced by high resolution transmission electron microscopy. The UV/Vis absorption of In2O3 nanocrystals was studied to estimate the bandgap energies. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Milk fatty acids: Mammary synthesis could limit transfer from duodenum in cows
Authors: Glasser Frédéric , Doreau Michel , Ferlay Anne , Loor Juan J. , Chilliard Yves
Published: August 2007

This study reports a quantitative analysis of two experiments comparing the effects of different dietary forage/concentrate ratios and lipid supplements on cow lipid digestion and milk fatty acid (FA) secretion. We studied, on an individual cow basis, the relationship between digestive variables [fiber intake and duodenal 18‐carbon (C18) FA flows], plasma FA content, milk FA yield and composition. Milk short‐ and medium‐chain FA (C4–C16) secretion depended mainly on additive effects of dietary fiber intake and lipid supplementation level. For high‐lipid diets (3–5% oil in dry matter intake), milk C18 secretion was proportional to C4–C16 secretion, independently of C18 dietary supply. For the low‐forage high‐lipid diet, C4–C16 secretion apparently limited C18 secretion, which represented only 36% of absorbed C18, compared to 79% with a high‐forage high‐lipid diet (higher C4–C16 secretion). Despite these high variations in total C18 secretion, the composition of milk C18 was not significantly different, within cows, from the duodenal C18 composition, when substrates and products of Δ‐9 desaturase were summed. Mammary desaturation activity (expressed in mol/day) was a linear function of the estimated mammary uptake of the substrates, and this endogenous production represented more than 75% of the milk secretion of the Δ‐9 desaturated products.
Assessing rumen biohydrogenation and its manipulation in vivo, in vitro and in situ
Authors: Fievez Veerle , Vlaeminck Bruno , Jenkins Tom , Enjalbert Francis , Doreau Michel
Published: August 2007

Reference techniques to study rumen biohydrogenation (BH) rely on the comparison of intake and duodenal or (ab)omasal flows of polyunsaturated fatty acids (PUFA), whereas the net BH of PUFA to their saturated end‐products gives a quantitative measure of accumulating BH intermediates. The current review paper aims at evaluating alternative in vivo, in vitro and in sacco techniques to simulate reference in vivo results of unprotected PUFA sources, as well as strategies for overcoming or manipulating BH. In vivo rumen sampling approaches show potential but require further investigation, whereas in sacco results are inappropriate. In vitro 24‐h batch incubations and continuous cultures approach in vivo BH of unprotected C18 PUFA sources and are useful to assess the pH value at which dissociation of calcium salts of fatty acids occurs, but overestimate the degree of rumen inertness of formaldehyde‐treated oil(seeds) and marine products. Batch or continuous cultures provide an accurate estimate (0.6) of the proportion of hydrogenated C18 PUFA that are converted into their saturated end‐product, except for incubations with high levels of fermentable substrate (>1.0 g/100 mL) in combination with high amounts of C18 PUFA (>0.5 mg/mL) or in incubations with EPA and DHA.
In vitro production of Mallory bodies and intracellular hyaline bodies: The central role of sequestosome 1 / p62
Authors: Stumptner Conny , Fuchsbichler Andrea , Zatloukal Kurt , Denk Helmut
Published: August 2007

Mallory bodies (MBs) and intracellular hyaline bodies (IHBs) are characteristic hepatocellular inclusions. MBs are hallmarks of steatohepatitis, whereas IHBs have first been detected in hepatocellular carcinoma. MBs and IHBs contain ubiquitin and sequestosome 1 / p62 (p62), a stress-inducible adapter protein with affinity to polyubiquitinated proteins. MBs differ from IHBs by their keratin content and morphology.

In vitro

transfections were undertaken to study under defined conditions MB and IHB formation, their pathogenesis, and relationship. CHO-K1, TIB73, and HeLa cells were transfected with keratin 8, keratin 18, ubiquitin, p62, and p62 lacking the ubiquitin binding domain (p62ΔUBA) and analyzed by immunofluorescence, immunoelectron microscopy, and immunoblotting. Transfection of p62 complementary deoxyribonucleic acid (cDNA) alone led to cytoplasmic aggregates consisting of filaments mostly arranged in parallel arrays resembling amyloid and type 1 MBs. Transfection of p62 and ubiquitin resulted in globular cytoplasmic aggregates with indistinct fibrillar ultrastructure resembling IHBs. Cotransfection of p62, keratin 8, and ubiquitin was necessary to produce

in vitro

type 2 MBs-like aggregates consisting of randomly oriented 10- to 15-nm filaments. A similar result was obtained when keratin 8 was replaced by keratin 18. After cotransfection of p62ΔUBA, keratin 8, and ubiquitin, keratin formed irregular aggregates with electron-dense granular-amorphous ultrastructure (resembling type 3 MBs), whereas p62ΔUBA remained in diffuse cytoplasmic distribution.

Conclusion:

Our studies show that

in vitro

development of classical type 2 MBs requires overexpression of keratin 8 (or keratin 18), ubiquitin, and p62 containing the ubiquitin binding domain, whereas IHBs result from overexpression of p62 together with ubiquitin without keratin involvement. (Hepatology 2007.)
Influence of ursodeoxycholic acid on the mortality and malignancy associated with primary biliary cirrhosis
Authors: Jackson Hannah , Solaymani-Dodaran Masoud , Card Tim R. , Aithal Guruprasad P. , Logan Richard , West Joe
Published: August 2007

There is debate over the mortality and malignancy risk in people with primary biliary cirrhosis (PBC) and whether this risk is reduced by use of ursodeoxycholic acid. To investigate this issue, we identified 930 people with PBC and 9,202 control subjects from the General Practice Research Database in the United Kingdom. We categorized regular ursodeoxycholic acid as treatment with 6 or more prescriptions and nonregular treatment as less than 6. We found a 2.7-fold increase in mortality for the PBC cohort compared with the general population [adjusted hazard ratio (HR), 2.69; 95% CI, 2.35–3.09]. In those having regular ursodeoxycholic acid (43%), the mortality increase was 2.2-fold (HR, 2.19; 95% CI, 1.66–2.87) and in those not treated 2.7-fold (HR, 2.69; 95% CI, 2.18–3.33). This apparent reduction in mortality was not explained by less severe disease in the ursodeoxycholic acid–treated group. The increased risk of primary liver cancer in ursodeoxycholic acid–treated patients was 3-fold (HR, 3.17; 95% CI, 0.64–15.62), in contrast to an 8-fold increase in those not treated (HR, 7.77; 95% CI, 1.30–46.65).

Conclusion:

We found that people with PBC had a 3-fold mortality increase when compared with the general population, which was somewhat reduced by regular treatment with ursodeoxycholic acid. However, the observed effect of ursodeoxycholic acid was not statistically significant. (HEPATOLOGY 2007.)
Targeting BCL‐2 family proteins to overcome drug resistance in non‐small cell lung cancer
Authors: Wesarg Emmanuelle , Hoffarth Sandra , Wiewrodt Rainer , Kröll Monika , Biesterfeld Stefan , Huber Christoph , Schuler Martin
Published: August 2007

Cytotoxic chemotherapies are standard of care for patients suffering from advanced non‐small cell lung cancer (NSCLC). However, objective responses are only achieved in 20% of cases and long‐term survival is rarely observed. Clinically applied anticancer drugs exert at least some of their activities by inducing apoptosis. A critical step in apoptotic signal transduction is the permeabilization of the mitochondrial outer membrane (MOM), which is regulated by the BCL‐2 family of proteins. Hence, therapeutic targeting of BCL‐2 proteins is a promising approach to increase the drug‐sensitivity of cancers. To this end we have assessed the impact of conditional expression of the proapoptotic multidomain (BH1‐2‐3) protein BAK, which directly permeabilizes the MOM, and the BH3‐mimetic ABT‐737, which acts indirectly by derepressing BH1‐2‐3 proteins, on apoptosis and drug sensitivity of NSCLC cells. Conditionally expressed BAK sensitized resistant NSCLC cells to drug‐induced apoptosis. In contrast, ABT‐737 was ineffective in those NSCLC cells expressing high levels of the anti‐apoptotic MCL‐1 protein. Tissue microarray analysis of tumor samples from 84 chemotherapy‐naïve NSCLC patients revealed MCL‐1 expression in 56% of cases, thus supporting the relevance of this resistance factor in a clinical setting. Enforced expression of the BH3‐only protein NOXA, which targets MCL‐1, overcame resistance to ABT‐737. Moreover, combining conditionally expressed BAK with ABT‐737 enhanced apoptosis in NSCLC cells independently of their MCL‐1 status. In conclusion, the heterogeneity of apoptosis defects observed in drug‐resistant NSCLC demands individually tailored molecular therapies. Targeting the MOM permeabilizer BAK appears to have a broader apoptogenic activity than the BH3‐only mimetic ABT‐737. © 2007 Wiley‐Liss, Inc.
PPARα and PP2A are involved in the proapoptotic effect of conjugated linoleic acid on human hepatoma cell line SK‐HEP‐1
Authors: Muzio Giuliana , Maggiora Marina , Oraldi Manuela , Trombetta Antonella , Canuto Rosa Angela
Published: August 2007

Conjugated linoleic acid (CLA), found in dairy products, in beef and lamb has been demonstrated to possess anticancer properties protecting several tissues from developing cancer. Moreover, it has been shown to modulate apoptosis in several cancer cell lines. The aim of this study was to investigate which signaling transduction pathways were modulated in CLA‐induced apoptosis in human hepatoma SK‐HEP‐1 cells. The cells exposed to CLA were evaluated for PPARα, PP2A, pro‐apoptotic proteins Bak, Bad and caspases, and anti‐apoptotic proteins Bcl‐2 and Bcl‐XL. Cells were also treated with okadaic acid, a PP2A inhibitor, or with Wy‐14643, a specific PPARα agonist. The CLA‐induced apoptosis was concomitant to the increase of percentage of cells in the S phase, PPARα, PP2A and pro‐apoptotic proteins; simultaneously, antiapoptotic proteins decreased. Inhibition of PP2A prevented apoptosis, and PPARα agonist showed similar effect as CLA. The increased PP2A could be responsible for the dephosphorylation of Bcl‐2 and Bad, permitting apoptotic activity of Bax and Bad. The increase of caspase 8 and 9 suggested that both the intrinsic and extrinsic apoptotic pathways were induced. PP2A was probably increased by PPARα, since putative PPRE sequences were found in genes encoding its subunits. In conclusion, CLA induces apoptosis in human hepatoma SK‐HEP‐1 cells, by increasing PPARα, PP2A and pro‐apoptotic proteins. © 2007 Wiley‐Liss, Inc.
Both ionically and enzymatically crosslinkable alginate–tyramine conjugate as materials for cell encapsulation
Authors: Sakai Shinji , Kawakami Koei
Published: August 2007

The swelling behavior of the structural material of cell‐enclosing capsules is a key factor for the successful transplantation of these capsules in the treatment of diseases. The present study aimed to develop cell‐enclosing capsules displaying minimal swelling under physiological conditions. We investigated the use of an alginate–tyramine conjugate synthesized by a carbodiimide/active‐ester coupling reaction. The conjugate gel crosslinked by calcium ions and peroxidase‐catalyzed oxidative coupling of phenols swelled less in saline than in unmodified alginate. The degree of swelling could be controlled by conjugate preparation conditions. The conjugate gel showed no obvious cytotoxicity for cells, including the process of oxidative coupling generation. Further, encapsulated cells could be cultured for up to 2 months and achieve ∼5.2‐fold greater mitochondrial activity after 51 days of encapsulation than after 1 day. These results show that this alginate–tyramine conjugate is a promising material for use in cell‐enclosing capsules for cell therapy. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Preparation of bone‐like apatite–collagen nanocomposites by a biomimetic process with phosphorylated collagen
Authors: Li Xiaoke , Chang Jiang
Published: August 2007

By imitating in vivo bone mineralization, bone‐like apatite–collagen nanocomposites were prepared by chemical phosphorylation of collagen and subsequent biomimetic growth of bone‐like nanoapatite on collagen nanofibers. Two steps were employed in the composites preparation. First, the collagen was phosphorylated by chemical treatment, which provides the nucleation sites for bone‐like apatite mineralization. The subsequent growth of bone‐like nanoapatite on the phosphorylated collagen nanofibers was performed in simulated body fluid (SBF). The characterization of the composites showed that the composites were composed of nanoapatite mineralized collagen nanofibers that exhibit similarity to natural bone in composition and crystal morphology. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Self‐setting properties and in vitro bioactivity of Ca3SiO5/CaSO4⋅1/2H2o composite cement
Authors: Zhao Wenyuan , Chang Jiang , Zhai Wanyin
Published: August 2007

In this study, a biphasic injectable bone substitute, based on tricalcium silicate (Ca3SiO5) and plaster (CaSO4⋅1/2H2O), is presented. The addition of CaSO4⋅1/2H2O could accelerate the hydration of Ca3SiO5, decrease the setting time, and improve the strength of the cement. The workable Ca3SiO5/CaSO4⋅1/2H2O pastes with a liquid to powder (L/P) ratio of 0.8–1.0 mL g−1 could be injected for 2–20 min (nozzle diameter 2.0 mm) and enabled initial setting times of 9–60 min. The setting process yielded cellular structures with compressive strength of 12.4–31.5 MPa after 2–28 days. The in vitro bioactivity of the paste was investigated by soaking in simulated body fluid (SBF) for 7 days. The result showed that although large amount of CaSO4⋅1/2H2O (30%) was added, the paste showed good ability to induce the formation of hydroxyapatite (HA). Furthermore, the Ca3SiO5/CaSO4⋅1/2H2O paste could degrade in Ringer's solution, and the dissolution extracts of the paste also had a stimulatory effect on L929 cell growth in certain concentration range. Our results indicated that Ca3SiO5/CaSO4⋅1/2H2O paste was bioactive and degradable, and showed excellent mechanical properties after self‐setting. Therefore, it may be a potential candidate for further investigation as injectable tissue repairing substitute. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Micro‐ and nanostructuring of freestanding, biodegradable, thin sheets of chitosan via soft lithography
Authors: Fernandez Javier G. , Mills Christopher A. , Martinez Elena , Lopez‐Bosque Maria J. , Sisquella Xavier , Errachid Abdelhamid , Samitier Josep
Published: August 2007

A technique for imparting micro‐ and nanostructured topography into the surface of freestanding thin sheets of chitosan is described. Both micro‐ and nanometric surface structures have been produced using soft lithography. The soft lithography method, based on solvent evaporation, has allowed structures ∼60 nm tall and ∼500 × 500 nm2 to be produced on freestanding ∼0.5 mm thick sheets of the polymer when cured at 293 K, and structures ∼400 nm tall and 5 × 5 μm2 to be produced when cured at 283 K. Nonstructured chitosan thin sheets (∼200 μm thick) show excellent optical transmission properties in the visible portion of the electromagnetic spectrum. The structured sheets can be used for applications where optical microscopic analysis is required, such as cell interaction experiments and tissue engineering. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Mechanical properties of calcium phosphate scaffolds fabricated by robocasting
Authors: Miranda Pedro , Pajares Antonia , Saiz Eduardo , Tomsia Antoni P. , Guiberteau Fernando
Published: August 2007

The mechanical behavior under compressive stresses of β‐tricalcium phosphate (β‐TCP) and hydroxyapatite (HA) scaffolds fabricated by direct‐write assembly (robocasting) technique is analyzed. Concentrated colloidal inks prepared from β‐TCP and HA commercial powders were used to fabricate porous structures consisting of a 3‐D tetragonal mesh of interpenetrating ceramic rods. The compressive strength and elastic modulus of these model scaffolds were determined by uniaxial testing to compare the relative performance of the selected materials. The effect of a 3‐week immersion in simulated body fluid (SBF) on the strength of the scaffolds was also analyzed. The results are compared with those reported in the literature for calcium phosphate scaffolds and human bone. The robocast calcium phosphate scaffolds were found to exhibit excellent mechanical performances in terms of strength, especially the HA structures after SBF immersion, indicating a great potential of this type of scaffolds for use in load‐bearing bone tissue engineering applications. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008