bluuebunny/crossref_metadata_2025 huggingface dataset:
Rational Approaches to the Design of Therapeutics Targeting Molecular Markers: The Case of Chronic Myelogenous Leukemia
Authors: SAGLIO GIUSEPPE , MOROTTI ALESSANDRO , MATTIOLI GIOVANNA , MESSA EMANUELA , GIUGLIANO EMILIA , VOLPE GISELLA , REGE‐CAMBRIN GIOVANNA , CILLONI DANIELA
Published: January 2005

Abstract: Progress in understanding the molecular basis of signal transmission and transduction has contributed substantially to clarifying the mechanisms of leukemogenesis and of leukemia progression and has led to the identification of a number of specific molecular targets for treatment. Chronic myeloid leukemia (CML) has provided one of the best models, as the identification of a leukemia‐specific hybrid tyrosine kinase (BCR‐ABL, p210, p190) has led to the identification and the successful therapeutic application of a powerful tyrosine kinase inhibitor, imatinib. The BCR‐ABL fusion gene is the result of a reciprocal translocation between the long arms of chromosomes 9 and 22, t(9;22)(q34;q11), which characterizes more than 95% of the cases of CML. The resulting chimeric proteins (P210 and P190), which retain a constitutively activated tyrosine kinase activity, have a causative role in the genesis of the leukemia process. In agreement with this observation, BCR‐ABL tyrosine kinase inhibitors have recently emerged as powerful new therapeutic tools, obtaining extraordinary results in early chronic‐phase CML as well as in more advanced phases of the disease. Although these results represent a remarkable breakthrough, there are still numerous issues, such as the emergence of resistance, that remain unsolved and that will need further investigation. In spite of its low incidence, CML remains a paradigmatic model for understanding the pathogenesis and therapeutic options of human leukemias.
Flow Cytometric Immunophenotyping Analysis of Patterns of Antigen Expression in Non‐Hodgkin's B Cell Lymphoma in Samples Obtained from Different Anatomic Sites
Authors: GERVASI FRANCESCO , LO VERSO RAFFAELLA , GIAMBANCO CATERINA , CARDINALE GIOVANNI , TOMASELLI CARMELA , PAGNUCCO GUIDO
Published: January 2005

Abstract: Multiparametric clinical flow cytometry has evolved from two‐parameter quantitative assessment of lymphocytes to assessment of many qualitative parameters of suspensions obtained from bone marrow, peripheral blood, and lymph nodes for hematopathology. Nowadays, lymphoma immunophenotyping is a necessary complement to morphology and molecular parameters in the diagnosis and monitoring of human hematopoietic malignancies. The aim of the present study was to determine whether immunophenotypic differences could be used to distinguish between non‐Hodgkin's B cell lymphoma (NHL‐B) and the normal B cell subpopulation by assessing the variability in the patterns of expression of some lymphoid antigens (CD5, CD19, FMC7, CD23, CD20, CD79b, CD38, CD22, CD10, sIgκ, sIgλ, mIgA, mIgG, mIgM, and mIgD) in specimens obtained from patients with NHL‐B. We have studied peripheral blood samples, lymph node suspensions, and bone marrow specimens from 20 patients with malignant lymphoma and from controls without oncohematologic disease. Some patients showed stable patterns of antigen expression that remained unchanged over time and were consistent from one specimen to another. Other patients showed more variability in the pattern of antigen expression from different specimens. The two‐way cluster analysis of antigens revealed three patterns of expression: (1) most cells in most cases positive (CD5, CD19, CD20, CD23, CD45); (2) most cells in most cases negative (CD10, mIgG, CD22, CD23,CD38); and (3) a mixed pattern with a variable number of positive cases and a variable percentage of positive cells in individual cases (CD22, CD38, CD79b, FMC7, mIgD, mIgM, mIgA, mIgG, sIgκ, sIgλ). The expression of several antigens was strongly interdependent, even when antigens belonged to entirely different gene families. Such antigen pairs were CD19/CD45; CD19/CD79b; CD23/Igκ; and CD45/CD79b. Our results suggest that different factors may determine the stability or the variability of such multiantigen expression, particularly the biology and function of the different antigens and the mechanisms of disease dissemination and progression.
Breast Cancer Incidence in the City and Province of Palermo in 1999‐2002: A Breast Cancer Registry Report
Authors: TRAINA ADELE , CUSIMANO ROSANNA , LIQUORI MAURIZIO , GUTTADAURO AGNESE , RAVAZZOLO BARBARA , PALUMBO FRANCESCO , CASTAGNETTA LUIGI
Published: January 2005

Abstract: The aim of this study was to assess the incidence of breast cancer in women from the city and province of Palermo (Sicily) in 1999, 2000, 2001, and 2002, using a population‐based cancer registry approach. In recent years, a sharp increase of breast cancer incidence has been observed worldwide. Overall, direct age‐standardized incidence rates (SIR) were 81.0 per 100,000 person‐years, higher in Palermo City (89.4) than in Palermo Province (70.4). Results reported here show a highly significant difference in breast cancer incidence in different areas of Sicily, particularly in the youngest age groups; and a profound difference between the metropolitan area of Palermo and the surrounding areas. The evidence of the different breast cancer incidence in Palermo City and in the other small municipalities of Palermo Province suggests a different cancer risk pattern that seems to be related to recent changes in lifestyle and diet.
A homologue of theDrosophilakinesin-like protein Costal2 regulates Hedgehog signal transduction in the vertebrate embryo
Authors: Tay Shang Yew , Ingham Philip W. , Roy Sudipto
Published: January 2005

Orthologues of nearly all of the core components of the Hedgehog signalling pathway, defined originally through genetic analysis in Drosophila,have now been discovered in vertebrates and shown to have highly conserved functions. The one striking exception to this rule is the kinesin-like protein Costal2, which plays a central role in controlling the activity of the zinc-finger-containing transcriptional regulator, Cubitus interruptus that modulates all Hedgehog-dependent target gene expression, but whose involvement in Hedgehog signalling has not been demonstrated in vertebrates. We report the cloning of a kinesin-related gene from the zebrafish that in structure as well as function, appears to represent the first vertebrate orthologue of costal2. Using a combination of genetic and biochemical analysis, we provide evidence that as in Drosophila, zebrafish Costal2 acts principally as an intracellular repressor of signal transduction, in conjunction with Suppressor of Fused, another protein that negatively regulates signalling in Hedgehog-responsive cells.
Specification of individual Slouch muscle progenitors inDrosophilarequires sequential Wingless signaling
Authors: Cox Virginia T. , Baylies Mary K.
Published: January 2005

The patterning of the Drosophila mesoderm requires Wingless (Wg),one of the founding members of a large family of secreted glycoproteins, the Wnt family. Little is known about how Wg provides patterning information to the mesoderm, which is neither an epithelium nor contains the site of Wg production. By studying specification of muscle founder cells as marked by the lineage-specific transcription factor Slouch, we asked how mesodermal cells interpret the steady flow of Wg. Through the manipulation of place, time and amount of Wg signaling, we have observed that Slouch founder cell cluster II is more sensitive to Wg levels than the other Slouch-positive founder cell clusters. To specify Slouch cluster I, Wg signaling is required to maintain high levels of the myogenic transcriptional regulator Twist. However, to specify cluster II, Wg not only maintains high Twist levels, but also provides a second contribution to activate Slouch expression. This dual requirement for Wg provides a paradigm for understanding how one signaling pathway can act over time to create a diverse array of patterning outcomes.
Lsh controls silencing of the imprinted Cdkn1c gene
Authors: Fan Tao , Hagan John P. , Kozlov Serguei V. , Stewart Colin L. , Muegge Kathrin
Published: January 2005

Epigenetic regulation, such as DNA methylation plays an important role in the control of imprinting. Lsh, a member of the SNF2 family of chromatin remodeling proteins, controls DNA methylation in mice. To investigate whether Lsh affects imprinting, we examined CpG methylation and allelic expression of individual genes in Lsh-deficient embryos. We report here that loss of Lsh specifically alters expression of the Cdkn1c gene (also known as p57(Kip2)) but does not interfere with maintenance of imprints at the H19, Igf2, Igf2r, Zac1 and Meg9 genes. The reactivation of the silenced paternal Cdkn1c allele correlates closely with a loss of CpG methylation at the 5′ DMR at the Cdkn1c promoter, whereas KvDMR1 and DMRs of other imprinted genes were not significantly changed. Chromatin immunoprecipitations demonstrate a direct association of Lsh with the 5′ DMR at the Cdkn1cpromoter, but not with Kv DMR1 or other imprinted loci. These data suggest that methylation of the 5′ DMR plays an important role in the imprinting of the Cdkn1c gene. Furthermore, it suggests that Lsh is not required for maintenance of imprinting marks in general, but is only crucial for imprinting at distinct genomic sites.
Drosophilaglypicans Dally and Dally-like shape the extracellular Wingless morphogen gradient in the wing disc
Authors: Han Chun , Yan Dong , Belenkaya Tatyana Y. , Lin Xinhua
Published: January 2005

Drosophila Wingless (Wg) is the founding member of the Wnt family of secreted proteins. During the wing development, Wg acts as a morphogen whose concentration gradient provides positional cues for wing patterning. The molecular mechanism(s) of Wg gradient formation is not fully understood. Here,we systematically analyzed the roles of glypicans Dally and Dally-like protein(Dlp), the Wg receptors Frizzled (Fz) and Fz2, and the Wg co-receptor Arrow(Arr) in Wg gradient formation in the wing disc. We demonstrate that both Dally and Dlp are essential and have different roles in Wg gradient formation. The specificities of Dally and Dlp in Wg gradient formation are at least partially achieved by their distinct expression patterns. To our surprise,although Fz2 was suggested to play an essential role in Wg gradient formation by ectopic expression studies, removal of Fz2 activity does not alter the extracellular Wg gradient. Interestingly, removal of both Fz and Fz2, or Arr causes enhanced extracellular Wg levels, which is mainly resulted from upregulated Dlp levels. We further show that Notum, a negative regulator of Wg signaling, downregulates Wg signaling mainly by modifying Dally. Last, we demonstrate that Wg movement is impeded by cells mutant for both dally and dlp. Together, these new findings suggest that the Wg morphogen gradient in the wing disc is mainly controlled by combined actions of Dally and Dlp. We propose that Wg establishes its concentration gradient by a restricted diffusion mechanism involving Dally and Dlp in the wing disc.
Visible-Light Sensitisation of Nanocrystalline TiO2 Film by Mg Chlorophyll-a through the Axial Imidazole-4-acetic Acid Ligand
Authors: Aoki Keiko , Takeuchi Yumi , Amao Yutaka
Published: January 2005

Mg chlorophyll-a (MgChl-a) with imidazole-4-acetic acid (Im) as the axial ligand (MgChl-a–Im), adsorbed on a nanocrystalline TiO2 film electrode, was prepared. Further, the photoelectrical properties of a solar cell using visible-light sensitisation of the nanocrystalline TiO2 film through an axial Im ligand of MgChl-a were investigated.
Evaluation of the 2-Substituent Effect on the Reactivity of the 8-Haloimidazo[1,2-a]pyridine Series towards Suzuki-Type Cross-Coupling Reaction
Authors: Kazock Jean-Yves , Enguehard-Gueiffier Cécile , Théry Isabelle , Gueiffier Alain
Published: January 2005

The purpose of this work was to complete a general study that we initiated on the influence of a 2-substitution on the reactivity of 8-haloimidazo[1,2-a]pyridines towards a Suzuki cross-coupling reaction, using conventional reactants in order to obtain easily performed (hetero)arylation methods with a high degree of flexibility with regard to functional groups.
Syntheses, Structures, and Properties of Quinone-Bridged Calix[6]arenes
Authors: Akine Shigehisa , Goto Kei , Kawashima Takayuki
Published: January 2005

The quinone-bridged calix[6]arenes 1 and 2, carrying a 1,4-benzoquinone moiety in the cavity of a calixarene macrocycle, were synthesized from the corresponding p-methoxyphenol derivatives. X-ray crystallography revealed the structures of 1 and 2, in which the quinone moiety is located inside the cone-shaped calix[6]arene framework and surrounded by the lower-rim substituents. Their 1H NMR spectra showed upfield shifts of the protons on the bridging unit in comparison with reference compounds without the calixarene framework, in accordance with their crystal structures. The cyclic voltammograms of 1 and 2 showed two waves, the second ones being considerably broadened. Their reduction potentials were found to be negatively shifted in comparison with those of the reference compounds. These shifts were explained in terms of the nonbonded interaction between the ether oxygen atoms of the calixarene moiety and the quinone moiety, as well as the sterically restricted access of the counter cation to the semiquinone anion radical. Reactions of 1 with hydroxylamine and phenylhydrazine afforded the corresponding hydroquinone along with the quinone monoimine derivatives, indicating that electron transfer from the amines proceeds quickly, although the negatively shifted reduction potentials of 1 are apparently unfavorable for the electron transfer process.
Synthesis and Properties of Novel Stilbazolium Analogues as Second-Order Nonlinear Optical Chromophores
Authors: Tsuji Kyoko , Nishimura Naoyuki , Duan Xuan-Ming , Okada Shuji , Oikawa Hidetoshi , Matsuda Hiro , Nakanishi Hachiro
Published: January 2005

This study synthesized a series of methoxystilbazolium analogues with π-conjugation extended by attaching a fused aromatic ring, i.e., 6-styrylisoquinolinium and 4-[2-(2-naphthyl)ethenyl]pyridinium derivatives with methoxy substituents. We evaluated their transition energies (Eegs) and second-order hyperpolarizabilities (βs) experimentally using their absorption spectra and a hyper-Rayleigh scattering measurement, respectively. Subsequently, we calculated βs using the MOPAC PM3 method. These values were compared with those of 4-[4-(4-methoxyphenyl)-1,3-butadienyl]pyridinium derivative, which is a stilbazolium analogue with π-conjugation that is simply extended by an increase of the double-bond number between two aromatic rings. This study clarified that the fused-ring systems possess large βs, irrespective of their relatively short absorption wavelengths, compared to the double-bond elongation system.
Redox Properties and Basicity of Keggin-Type Polyoxometalate Complexes
Authors: Himeno Sadayuki , Takamoto Masayo , Santo Ryoko , Ichimura Akio
Published: January 2005

For Keggin-type polyoxometalate complexes (α-[XMo12O40]n− (X = S, P, As, Si, Ge; n = 2–4) and α-[XW12O40]n− (X = S, P, As, Si, Ge, B, Al; n = 2–5)), the conversion processes of the first two one-electron waves into a two-electron wave were investigated in dipolar aprotic solvents containing H+, Li+, or Na+ as a Lewis acid. A simulation of the cyclic voltammogram indicated that the potential difference (ΔEmid) between the first one- and two-electron redox waves served as a useful criterion for the basicity of the Keggin anions. According to the ΔEmid values, the Keggin anions were classified into the following four groups: (1) [SW12O40]2−; (2) [SMo12O40]2−, [XW12O40]3− (X = P, As); (3) [XMo12O40]3− (X = P, As), [XW12O40]4− (X = Si, Ge); (4) [XMo12O40]4− (X = Si, Ge), [XW12O40]5− (X = B, Al). The voltammetric properties of the Keggin anions were systematized with reference to their basicities.
Preparation of Tetrahedral Pt Nanoparticles Having {111} Facet on Their Surface
Authors: Miyazaki Akane , Yoshida Shuichiro , Nakano Yoshio , Balint Ioan
Published: January 2005

{100} and {111} facets are typical for metal clusters having FCC structure. We have ever succeeded to obtain square Pt particles having {100} facet on their surface. However, there has not been an effective method to obtain Pt nanoparticles with the other facets, i.e., {111}. In this paper we report a novel preparation method of tetrahedral Pt nanoparticles, whose surface is controlled {111}, by using a thermosensitive capping polymer [poly(N-ethylacrylamide)].
Activation of Urea as a Leaving Group in Substitution Reactions of Formamidine Ureas
Authors: Díaz David D , Lewis Warren G , Finn M G
Published: January 2005

The reactions of formamidine ureas with amines take different paths under protic vs. nonprotic conditions; loss of the urea fragment has been observed for the first time when protons are made available intra- or intermolecularly.
Petrochemicals, Feedstocks
Authors: Boepple John T.
Published: January 2005

Petrochemicals are derived from natural gas or petroleum and can be broadly classified as olefins or aromatics. The choice of feedstock for a given operator is primarily an economic issue, but may be constrained by technical considerations or local availability of indigenous hydrocarbons. Feedstock economics are influenced by fuels products markets and the seasonal effects in fuels prices. Olefins are produced primarily by the thermal cracking of hydrocarbon feedstocks such as ethane, propane, naphtha, or gas oil. In the United States, the most important olefin feedstocks are ethane and propane, which are recovered from natural gas, whereas in most of the rest of the world naphthas are the dominant feedstocks. Lesser quantities of olefins, primarily propylene, are produced from refinery gas streams. Aromatics are recovered from refinery catalytic reformer operations and pyrolysis gasoline from olefin plants based on naphtha or gas oil feedstock. In the United States, reformer operations are the most important source; in the rest of the world, pyrolysis gasoline is the dominant feedstock. Although alternative feedstocks have been the subject of much research, only minimal usage can be expected over the coming decades.
Poly(Fluorosilicones)
Authors: Romenesko David J. , Chorvath Igor , Olsen Charles W. , Tonge Lauren M.
Published: January 2005

Poly(fluorosilicones) are siloxane polymers with fluorinated organic substituents bonded to silicon. The combination of fluoro‐organic and siloxane properties in one material has many unique applications. The monomer and polymer preparations are reviewed for the manufacture of poly(3,3,3‐trifluoropropyl)methylsiloxane and related poly(fluorosilicones). The polymers and their materials' application properties are discussed with a correlation to chemical structure and stability. The processing, compounding, and curing of the poly(fluorosilicones) into fluids, sealants, rubber, and related applications are described, along with information on safe handling characteristics. Specific examples of applications are covered. An estimation of global capacity is given along with a perspective on market aspects.
Nonwoven Fabrics, Staple Fibers
Authors: Chapman Roger
Published: January 2005

This article provides an overview of the production methods, properties, and uses of nonwoven fabrics. The discussion includes a brief introduction, short history, and compilation of definitions of a nonwoven fabric. Staple fiber processes, including fiber selection, web formation, web layering, web consolidation, and finishing, are described. Descriptions and illustrations of the manufacturing sequences follow. Production trends and product applications are discussed.
Process Design
Authors: Smith Robin
Published: January 2005

Chemical process design requires the selection of a series of processing steps and their integration to form a complete manufacturing system. Once a structure for the process has been established, then a mathematical model of the process can be developed and the process simulated. The type of product, scale of production, and life cycle of the product have major influences on the priorities in chemical process design. Short life cycles require the design of multi‐product processes.

Chemical processing should form part of a sustainable industrial activity. For chemical processing, this means that processes should use raw materials and energy as efficiently as is economic and practicable, both to prevent the production of waste that can be environmentally harmful and to preserve the reserves of raw materials and energy as much as possible. All aspects of chemical processing must feature good health and safety practice.

The design might be a new design or the retrofit of an existing process. If the design is a retrofit, then one of the objectives should be to maximize the use of existing equipment, even if it is not ideally suited to its new purpose. Both continuous and batch process operation can be used.
Transparent Poly(methyl methacrylate)/Single‐Walled Carbon Nanotube (PMMA/SWNT) Composite Films with Increased Dielectric Constants
Authors: Clayton L. M. , Sikder A. K. , Kumar A. , Cinke M. , Meyyappan M. , Gerasimov T. G. , Harmon J. P.
Published: January 2005

Poly(methyl methacrylate)/single‐walled carbon nanotube (PMMA/SWNT) composites were prepared via in situ polymerization induced either by heat, ultraviolet (UV) light, or ionizing (gamma) radiation. The composites dissolved in methylene chloride and then cast into films exhibited enhanced transparency as compared with the melt‐blended composite material. UV/visible spectroscopy was used to quantitatively analyze the transparency of the composites. The dielectric constant (ε′) was measured via dielectric analysis (DEA) and correlated to the refractive‐index values using Maxwell's relationship. The dielectric constant increased in the composite samples as compared with the neat PMMA samples prepared by the same methods. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) provided images of the polymer–nanotube composites and single‐walled CNTs, respectively.
Li6ALa2Ta2O12 (A = Sr, Ba): Novel Garnet‐Like Oxides for Fast Lithium Ion Conduction
Authors: Thangadurai V. , Weppner W.
Published: January 2005

Oxides with the nominal chemical formula Li6ALa2Ta2O12 (A = Sr, Ba) have been prepared via a solid‐state reaction in air using high purity La2O3, LiOH·H2O, Sr(NO3)2, Ba(NO3)2, and Ta2O5 and are characterized by powder X‐ray diffraction (XRD) in order to identify the phase formation and AC impedance to determine the lithium ion conductivity. The powder XRD data of Li6ALa2Ta2O12 show that they are isostructural with the parent garnet‐like compound Li5La3Ta2O12. The cubic lattice parameter was found to increase with increasing ionic size of the alkaline earth ions (Li6SrLa2Ta2O12: 12.808(2) Å; Li6BaLa2Ta2O12: 12.946(3) Å). AC impedance results show that both the strontium and barium members exhibit mainly a bulk contribution with a rather small grain‐boundary contribution. The ionic conductivity increases with increasing ionic radius of the alkaline earth elements. The barium compound, Li6BaLa2Ta2O12, shows the highest ionic conductivity, 4.0×10–5 S cm–1 at 22 °C with an activation energy of 0.40 eV, which is comparable to other lithium ion conductors, especially with the presently employed solid electrolyte lithium phosphorus oxynitride (Lipon) for all‐solid‐state lithium ion batteries. DC electrical measurements using lithium‐ion‐blocking and reversible electrodes revealed that the electronic conductivity is very small, and a high electrochemical stability (> 6 V/Li) was exhibited at room temperature. Interestingly, Li6ALa2Ta2O12 was found to be chemically stable with molten metallic lithium.
Improving the Brightness and Daylight Contrast of Organic Light‐Emitting Diodes
Authors: Vaenkatesan V. , Wegh R. T. , Teunissen J.‐P. , Lub J. , Bastiaansen C. W. M. , Broer D. J.
Published: January 2005

For most applications of displays based on organic light‐emitting diodes (LEDs), it is desirable to have good daylight contrast in combination with a high intensity of emitted light. The conventional approaches to enhance the daylight contrast, using a black cathode or circular polarizers, result in a significant loss of light emitted by the LED. A rather novel approach to enhance daylight contrast while keeping loss of emitted light to a minimum is the introduction of a chiral‐nematic film in the device. This approach leads to an increase in light efficiency by a factor of 1.8 (with respect to circular polarizers) with some loss in daylight contrast values within the reflection band of the chiral‐nematic film. Outside the reflection band, however, the contrast approaches infinity.
Influence of Side‐Chain Structure and Irradiation Condition on Photoalignment of Ladder‐Like Polysiloxane Films
Authors: Gu H.‐W. , Xie P. , Fu P.‐F. , Zhang T.‐Y. , Zhang R.‐B.
Published: January 2005

In this paper we consider the photo‐induced aligning capability of various ladder‐like polysiloxane‐based photoalignment films—which could be used in liquid‐crystal displays—bearing different photoreactive side chains, i.e., laterally grafted cinnamate/azobenzene‐based dual photoreactive side chains with a short or longer spacer, and terminally fixed coumarin‐containing side chains. Results from polarized optical microscopy (POM), Fourier‐transform infrared (FTIR) spectroscopy, surface‐enhanced Raman scattering (SERS), atomic force microscopy (AFM), etc., are integrated to elucidate the influence of side‐chain structure and the irradiation conditions on the photoalignment of ladder‐like polysiloxane films. It is demonstrated that the film containing the dual photoreactive group with a longer spacer exhibits better alignment properties. Reasonably, the concerted photoreactions of the dual photoreactive group and the longer spacer are beneficial to the cooperative motion of chromophores at the “domain level”, resulting in improved alignment facility and stability. The complicated effects of irradiation conditions and moderate annealing are also discussed. High‐quality alignment of the polysilsesquioxane (LPS)‐based photoalignment film LPS‐CA11 with a longer spacer between the LPS main chain and cinnamoyl/azobenzene side chains can be achieved only within an optimal range of exposure (5–8 J cm–2), while the pretilt angles can be adjusted in the range 0.5°–7° by varying the incident light intensity. Additionally, moderate annealing before and after illumination can markedly improve the alignment uniformity by self‐healing of defects.
Preparation of Hollow Silica Nanospheres by Surface‐Initiated Atom Transfer Radical Polymerization on Polymer Latex Templates
Authors: Chen Y. , Kang E. T. , Neoh K. G. , Greiner A.
Published: January 2005

Poly(vinylbenzyl chloride), (PVBC) latex particles of about 100 nm in size are prepared by emulsion polymerization. Silyl functional groups are introduced onto the PVBC‐nanoparticle templates via surface‐initiated atom transfer radical polymerization of 3‐(trimethoxysilyl)propyl methacrylate. The silyl groups are then converted into a silica shell, approximately 20 nm thick, via a reaction with tetraethoxysilane in ethanolic ammonia. Hollow silica nanospheres are finally generated by thermal decomposition of the PVBC template cores. Field‐emission scanning electron microscopy and field‐emission transmission electron microscopy are used to characterize the intermediate products and the hollow nanospheres. Fourier‐transform infrared spectroscopy results indicate that the polymer cores are completely decomposed.
Formation of Oxynitride as the Photocatalytic Enhancing Site in Nitrogen‐Doped Titania Nanocatalysts: Comparison to a Commercial Nanopowder
Authors: Chen X. , Lou Y.‐B. , Samia A. C. S. , Burda C. , Gole J. L.
Published: January 2005

A nitrogen‐doped TiO2 nanocolloid has been successfully prepared and its properties compared with the commercially available TiO2 nanomaterial, Degussa P25. Several characterization techniques, X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), transmission electron spectroscopy (TEM), Fourier transform infrared (FT‐IR) spectroscopy, Raman scattering, and UV‐visible reflectance spectra, are combined in order to determine the crystal phase and grain size, shape, degree of nitrogen incorporation, and nature of the resultant oxynitride chemical bonding on the surface and in the bulk. The high relative photocatalytic activity of the nitrogen doped‐TiO2 nanocolloid is evaluated through a study of the decomposition of methylene blue under visible light excitation. The ease and degree of substitutional‐insertional nitrogen doping is held accountable for the significant increase in photocatalytic activity in the porous nanocolloid versus the nitrided commercial nanopowder. It is suggested that the nitrogen incorporation produces an NO bonding region as evidenced by the resulting XPS spectrum.
Growing Strong
Authors: Levy E.
Published: January 2005

As Advanced Functional Materials enters its fifth year, the Editor describes the rapid growth of the journal in every sense, and how it is changing to adapt to its ever‐expanding author‐ and readership.
Permeability of subcritical hydrocarbons in activated carbon
Authors: Bae Jun‐Seok , Do D. D.
Published: January 2005

A new diffusion and flow model is presented to describe the behavior of hydrocarbon vapors in activated carbon. The micro/mesopore size distribution (PSD) is obtained according to Do's method which consists of two sequential processes of pore layering and pore filling. This model uses the micro/meso PSD obtained from each adsorbate equilibrium isotherm, which reflects the dynamics behavior of adsorbing molecules through the solid. The initial rise in total permeability is mainly attributed to adsorbed‐phase diffusion (that is, surface diffusion), whereas the decrease over reduced pressure of about 0.9 is attributed to the reduction of pore space available for gas phase diffusion and flow. A functional form of surface diffusivity is proposed and validated with experimental data. This model predicts well the permeability of condensable hydrocarbon vapors in activated carbon. © 2005 American Institute of Chemical Engineers AIChE J, 51: 487–501, 2005
Personality traits as intermediary phenotypes in suicidal behavior: Genetic issues
Authors: Baud Patrick
Published: January 2005

A genetic contribution to the risk of suicidal behavior is now supported by many studies. It probably involves specific factors acting on their own, independently of the genetic transmission of associated psychiatric disorders. A history of childhood maltreatment, adverse events, psychosocial stress, psychological traits and major psychiatric disorders all appear to contribute to the global risk of suicide attempt or completion. The interplay between previously identified risk factors, different as they are in nature and degree of complexity, still remains to be clarified. A stress‐diathesis model has been proposed, where trait‐like genetic and developmental risk factors (the diathesis) interact through still unknown mechanisms with actual (stress‐related) factors to create the conditions for a suicidal gesture. Disentangling the effects of these risk factors, and specifically the effects of the genetic factors influencing these different pathological conditions, appears to be a difficult task. Indeed the results of candidate gene association studies suggest that genetic vulnerability factors for various related psychiatric phenotypes (major psychiatric disorders and personality traits) partly overlap with more specific factors predisposing to suicidal behavior. Personality traits are partly under genetic control and may be closer to the genetic effects than psychiatric syndromes. We review here the available data on the genetics of personality traits presumably involved in suicidal behavior, focusing on the association studies carried out with serotonin‐related genes. We suggest that future studies on the genetic vulnerability to suicidal behavior should include the investigation of endophenotypes, with the aim of deciphering the mechanisms underlying the genetic susceptibility to these closely associated phenotypes. © 2005 Wiley‐Liss, Inc.
Improvement of the polarity of polyethylene with oxidized Fischer–Tropsch paraffin wax and its influence on the final mechanical properties
Authors: Novák I. , Krupa I. , Luyt A. S.
Published: January 2005

The easy, low‐cost modification of the polarity of low‐density polyethylene (LDPE) and high‐density polyethylene (HDPE) through blending with oxidized Fischer–Tropsch wax was investigated. A 10 wt % concentration of the wax increased the polar component of the total surface free energy 10 times for LDPE and 4.5 times for HDPE. Modified LDPE also had significantly higher adhesion to the polar substrate, which was represented by a crosslinked epoxy‐based resin. This behavior was not observed for HDPE. The conservation of the good mechanical properties of polyethylene was observed. The wax content had only a moderate influence on the mechanical properties. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1164–1168, 2005
Structure and properties of phenolic resin/nanoclay composites synthesized by in situ polymerization
Authors: Pappas Jonathan , Patel Kandarp , Nauman E. B.
Published: January 2005

An in situ semibatch polymerization process for making phenolic resin/montmorillonite clay nanocomposites is developed. It is found that auxiliary mixing in phenol allows intercalation of the monomer and polymer between montmorillonite clay layers. At 2.7% clay by mass the montmorillonite is predominantly exfoliated (fully dispersed). At higher clay loading, a substantial amount of the clay remains in aggregate or intercalated form. When the montmorillonite is exfoliated, the material is mechanically superior. The composite has a tensile modulus that is 21% higher than the neat resin and has 87% improved fracture strength, 100% larger fracture energy, and strain to failure 13% above the pure resin. Thermogravimetric analysis shows the montmorillonite system maintains its thermal stability up to 200°C. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1169–1174, 2005
Propylene–ethylene random copolymers: Comonomer effects on crystallinity and application properties
Authors: Gahleitner Markus , Jääskeläinen Pirjo , Ratajski Ewa , Paulik Christian , Reussner Jens , Wolfschwenger Johannes , Neißl Wolfgang
Published: January 2005

For understanding the correlation chain from the polymer structure to the final application properties of propylene–ethylene random copolymers, four commercial grades with different ethylene content (0–8 mol %) but identical molecular weight distributions were investigated. Structural investigations concerning the comonomer distribution, using two different techniques (temperature rising elution fractionation and stepwise isothermal segregation), showed an increase of inhomogeneity with the total comonomer content, which was reflected for temperature rising elution fractionation in a widening of the elution temperature range. Crystallinity and crystallization speed studies confirmed the reduced overall crystallinity and increase of γ‐modification content as reported previously, but they also showed the reason for these effects in the distinctive decrease of the spherulitic growth speed. Good correlations of all these parameters to the mechanical performance of the four materials were obtained. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1073–1081, 2005
Synthesis and chain extension of poly(L‐lactic acid‐co‐succinic acid‐co‐1,4‐butene diol)
Authors: Lee Choon Mee , Kim Hun Sik , Yoon Jin San
Published: January 2005

L‐Lactic acid (LA) was copolymerized with succinic acid (SA) and 1,4‐butenediol (1,4‐BED) in bulk state with titanium(IV) butoxide as a catalyst to produce poly(LA‐co‐SA‐co‐1,4‐BED) (PLASBED). Poly(L‐lactic acid) (PLLA) homopolymer obtained from a direct condensation polymerization of LA had weight average molecular weight (Mw) less than 4.1 × 104 and was too brittle to prepare specimens for the tensile test. Addition of SA and 1,4‐BED to LA produced PLASB with Mw as high as 1.4 × 105 and exhibited tensile properties comparable to a commercially available high‐molecular‐weight PLLA. Chain extension by intermolecular linking reaction through the unsaturated 1,4‐BED units in PLASBED with benzoyl peroxide further increased the molecular weight and made PLASBED more ductile and flexible to show elongation at break as high as 450%. Biodegradability of PLASBED measured by the modified Sturm test was nearly independent of the 1,4‐BED content. Gel formation during the chain extension did not exert any significant influence on the biodegradability either. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1116–1121, 2005
CYP2D6 and CYP1A1 mutations in the Turkish population
Authors: Aydin Muge , Hatirnaz Ozden , Erensoy Nevin , Ozbek Ugur
Published: January 2005

Drugs and carcinogens are substrates of a group of metabolic enzymes including cytochrome p450 enzymes and gluthatione S‐transferases. Many of the genes encoding these enzymes exhibit functional polymorphisms that contribute individual cancer susceptibility and drug response. Molecular studies based on these polymorphic enzymes also explain the aetiology of cancer and therapeutic management in clinics. We analysed the cytochrome p4501A1 (CYP1A1) and 2D6 (CYP2D6) variant genotype and allele frequencies by PCR‐RFLP in Turkish individuals (n = 140). The frequency of the CYP1A1*2A mutant allele was found to be 15.4%, and the CYP2D6*3 and *4 mutant allele (poor metabolizer) frequencies were 2.5% and 13.9%, respectively. This study presents the first results of CYP1A1 and CYP2D6 mutant allele distributions in the Turkish population and these data provide an understanding of epidemiological studies that correlate therapeutic approaches and aetiology of several types of malignancy in Turkish patients. Copyright © 2005 John Wiley & Sons, Ltd.
Induction of DNA‐Double‐Strand Breaks by Auger Electrons from 99mTc Complexes with DNA‐Binding Ligands
Authors: Häfliger Pascal , Agorastos Nikos , Spingler Bernhard , Georgiev Oleg , Viola Giampietro , Alberto Roger
Published: January 2005

The potential of certain Auger electron emitting nuclides for systemic radiotherapeutic applications has recently gained much attention. In particular, the ability of several nuclides, including 111In, 125I, and 123I, to induce DNA double‐strand breaks (dsb), a good indicator of cytotoxicity, has been extensively studied. However, this ability has never previously been shown experimentally for 99mTc, which, besides the well‐known γ radiation that is used for diagnostic applications, also emits an average of 1.1 conversion electrons and 4 Auger or Coster–Kronig electrons per decay. Owing to the short range of Auger electrons, the radionuclide needs to be located very close to the DNA for dsb to occur. We synthesized two cationic 99mTcI–tricarbonyl complexes with pendant DNA binders, pyrene and anthraquinone. The X‐ray crystal structures of the two complexes could be elucidated. Linear dichroism and UV/Vis spectroscopy revealed that the complex with pyrene intercalates DNA with a stability constant, K, of 1.1×106 M−1, while the analogous complex with anthraquinone interacts with DNA in a groove‐binding mode and has an affinity value of K=8.9×104 M−1. We showed with ϕX174 double‐stranded DNA that the corresponding 99mTc complexes induce a significant amount of dsb, whereas non‐DNA‐binding [TcO4]− and nonradioactive Re compounds did not. These results indicate that the Auger electron emitter 99mTc can induce dsb in DNA when decaying in its direct vicinity and this implies potential for systemic radiotherapy with 99mTc complexes.
A New Type of Metalloprotein: The Mo Storage Protein from Azotobacter vinelandii Contains a Polynuclear Molybdenum–Oxide Cluster
Authors: Fenske Dirk , Gnida Manuel , Schneider Klaus , Meyer‐Klaucke Wolfram , Schemberg Jörg , Henschel Volker , Meyer Anne‐Katrin , Knöchel Arndt , Müller Achim
Published: January 2005

Azotobacter vinelandii is a diazotrophic bacterium characterized by the outstanding capability of storing Mo in a special storage protein, which guarantees Mo‐dependent nitrogen fixation even under growth conditions of extreme Mo starvation. The Mo storage protein is constitutively synthesized with respect to the nitrogen source and is regulated by molybdenum at an extremely low concentration level (0–50 nM). This protein was isolated as an α4β4 octamer with a total molecular mass of about 240 kg mol−1 and its shape was determined by small‐angle X‐ray scattering. The genes of the α and β subunits were unequivocally identified; the amino acid sequences thereby determined reveal that the Mo storage protein is not related to any other known molybdoprotein. Each protein molecule can store at least 90 Mo atoms. Extended X‐ray absorption fine‐structure spectroscopy identified a metal–oxygen cluster bound to the Mo storage protein. The binding of Mo (biosynthesis and incorporation of the cluster) is dependent on adenosine triphosphate (ATP); Mo release is ATP‐independent but pH‐regulated, occurring only above pH 7.1. This Mo storage protein is the only known noniron metal storage system in the biosphere containing a metal–oxygen cluster.
The Functional Role of Selenocysteine (Sec) in the Catalysis Mechanism of Large Thioredoxin Reductases: Proposition of a Swapping Catalytic Triad Including a Sec‐His‐Glu State
Authors: Brandt Wolfgang , Wessjohann Ludger A.
Published: January 2005

Thioredoxin reductases catalyse the reduction of thioredoxin disulfide and some other oxidised cell constituents. They are homodimeric proteins containing one FAD and accepting one NADPH per subunit as essential cofactors. Some of these reductases contain a selenocysteine at the C terminus. Based on the X‐ray structure of rat thioredoxin reductase, homology models of human thioredoxin reductase were created and subsequently docked to thioredoxin to model the active complex. The formation of a new type of a catalytic triad between selenocysteine, histidine and a glutamate could be detected in the protein structure. By means of DFT (B3LYP, lacv3p**) calculations, we could show that the formation of such a triad is essential to support the proton transfer from selenol to a histidine to stabilise a selenolate anion, which is able to interact with the disulfide of thioredoxin and catalyses the reductive disulfide opening. Whereas a simple proton transfer from selenocysteine to histidine is thermodynamically disfavoured by some 18 kcal mol−1, it becomes favoured when the carboxylic acid group of a glutamate stabilises the formed imidazole cation. An identical process with a cysteine instead of selenocysteine will require 4 kcal mol−1 more energy, which corresponds to a calculated equilibrium shift of ∼1000:1 or a 103 rate acceleration: a value close to the experimental one of about 102 times. These results give new insights into the catalytic mechanism of thioredoxin reductase and, for the first time, explain the advantage of the incorporation of a selenocysteine instead of a cysteine residue in a protein.
Kinetics Study of Bungarus fasciatus Venom Acetylcholinesterase Immobilised on a Langmuir–Blodgett Proteo‐Glycolipidic Bilayer
Authors: Godoy Stéphanie , Violot Sébastien , Boullanger Paul , Bouchu Marie‐Noëlle , Leca‐Bouvier Béatrice D. , Blum Loïc J. , Girard‐Egrot Agnès P.
Published: January 2005

This study deals with the kinetics properties of an enzyme immobilised in a defined orientation in a biomimetic environment. For this purpose, acetylcholinesterase (AChE) was captured at the surface of a nanostructured proteo‐glycolipidic Langmuir–Blodgett film through specific recognition by a noninhibitor monoclonal antibody (IgG) inserted in a neoglycolipid bilayer. Modelling of this molecular assembly provided a plausible interpretation of the functional orientation of the enzyme. The AChE activity being stable for several weeks, the enzyme kinetics were investigated, and fitted perfectly with heterogeneous biocatalytic behaviour representative of cellular enzymatic catalysis. The AChE–IgG–glycolipid nanostructure was directly interfaced with an efficient optical device. Such an association, leading to an intimate contact between the nanostructure and the biochemical signal transducer, gives direct access to the intrinsic AChE behaviour. This study thus demonstrates the potential for direct investigation of the kinetic behaviour of an immobilised enzyme on a lipid bilayer through an efficient transduction system.
Primary chemotherapy with cyclophosphamide, methotrexate, and 5‐fluorouracil in operable breast carcinoma
Authors: Falo Catalina , Moreno Abelardo , Benito Enrique , Lloveras Belen , Varela Mar , Serra Jose Ma , Prieto Luis , Azpeitia Diego , Escobedo Agustin
Published: January 2005

BACKGROUND

Primary chemotherapy (PC) is becoming an accepted practice to treat large tumors to avoid mastectomies and as a surrogate of outcome.

METHODS

A series of 305 patients with tumors > 3 cm with T2–3N0–1M0 classification were treated with a multimodal approach that consisted of 3 courses of primary cyclophosphamide, methotrexate, and 5‐fluorouracil (CMF) followed by appropriate local treatment and 3 more courses of CMF or 4 courses of doxorubicin. Response was assessed by mammography.

RESULTS

The overall response rate was 48% (a 3% pathologic complete response rate). Conservative surgery was achieved in 79.64% of the patients with a low rate of local disease recurrences (5%). Toxicity was minimal. With a median follow‐up of 104 months, the 8‐year disease‐free survival (DFS) rate was 57.63% and the 8‐year overall survival (OS) was 67.65%. The DFS and OS rates for patients with a clinical response were significantly longer, i.e., 70% (P = 0.0048) and 90% (P = 0.0042), respectively.

CONCLUSIONS

PC with CMF was feasible. A high rate of breast‐conservative surgery was achieved. The current results stressed the value of PC to increase conservative surgery and as a predictor of outcome. Cancer 2005. © 2005 American Cancer Society.
More on the evolution of bed material waves in alluvial rivers
Authors: Cui Yantao , Parker Gary , Lisle Thomas E. , Pizzuto James E. , Dodd Annjanette M.
Published: January 2005

Sediment waves or pulses can form in rivers following variations in input from landslides, debris ﬂows, and other sources. The question as to how rivers cope with such sediment inputs is of considerable practical interest. Experimental, numerical and ﬁeld evidence assembled by the authors suggests that in mountain gravel‐bed streams, such pulses show relatively little translation, instead mostly dispersing in place. This research has recently been the subject of discussion. In particular it has been suggested that (a) the equations of ﬂow and sediment mass balance used in the analyses, and in most other morphodynamic analyses, require correction; (b) the dominance of dispersion appears only because the hyperbolic nature of the governing equations has not been adequately considered; and (c) the sediment transport equation used in the analyses does not lead to generalizable results. Here we suggest that (a) the relations for mass balance do not require the indicated correction; (b) the hyperbolic nature of the governing equations does not preclude the result of dispersion dominating translation in mountain streams; and (c) the general behaviour of an appropriate hyperbolic model of sediment waves (pulses) includes the relative roles of dispersion and translation, and is not affected by the precise choice of a sediment transport relation (as long as the choice is reasonable for the case in question). Copyright © 2005 John Wiley & Sons, Ltd.