bluuebunny/crossref_metadata_2025_split huggingface dataset:
The HOX genes are expressed, in vivo, in human tooth germs: In vitro cAMP exposure of dental pulp cells results in parallel HOX network activation and neuronal differentiation
Authors: D'Antò Vincenzo , Cantile Monica , D'Armiento Maria , Schiavo Giulia , Spagnuolo Gianrico , Terracciano Luigi , Vecchione Raffaela , Cillo Clemente 
Published: October 2005

AbstractHomeobox‐containing genes play a crucial role in odontogenesis. After the detection of Dlx and Msx genes in overlapping domains along maxillary and mandibular processes, a homeobox odontogenic code has been proposed to explain the interaction between different homeobox genes during dental lamina patterning. No role has so far been assigned to the Hox gene network in the homeobox odontogenic code due to studies on specific Hox genes and evolutionary considerations. Despite its involvement in early patterning during embryonal development, the HOX gene network, the most repeat‐poor regions of the human genome, controls the phenotype identity of adult eukaryotic cells. Here, according to our results, the HOX gene network appears to be active in human tooth germs between 18 and 24 weeks of development. The immunohistochemical localization of specific HOX proteins mostly concerns the epithelial tooth germ compartment. Furthermore, only a few genes of the network are active in embryonal retromolar tissues, as well as in ectomesenchymal dental pulp cells (DPC) grown in vitro from adult human molar. Exposure of DPCs to cAMP induces the expression of from three to nine total HOX genes of the network in parallel with phenotype modifications with traits of neuronal differentiation. Our observations suggest that: (i) by combining its component genes, the HOX gene network determines the phenotype identity of epithelial and ectomesenchymal cells interacting in the generation of human tooth germ; (ii) cAMP treatment activates the HOX network and induces, in parallel, a neuronal‐like phenotype in human primary ectomesenchymal dental pulp cells. J. Cell. Biochem. 97: 836–848, 2006. © 2005 Wiley‐Liss, Inc.
Endothelin‐1 impairs glucose transporter trafficking via a membrane‐based mechanism
Authors: Strawbridge Andrew B. , Elmendorf Jeffrey S. 
Published: October 2005

AbstractEndothelin‐1 (ET‐1) disrupts insulin‐regulated glucose transporter GLUT4 trafficking. Since the negative consequence of chronic ET‐1 exposure appears to be independent of signal disturbance along the insulin receptor substrate‐1/phosphatidylinositol (PI) 3‐kinase (PI3K)/Akt‐2 pathway of insulin action, we tested if ET‐1 altered GLUT4 regulation engaged by osmotic shock, a PI3K‐independent stimulus that mimics insulin action. Regulation of GLUT4 by hyperosmotic stress was impaired by ET‐1. Because of the mutual disruption of both insulin‐ and hyperosmolarity‐stimulated GLUT4 translocation, we tested whether shared signaling and/or key phosphatidylinositol 4,5‐bisphosphate (PIP2)‐regulated cytoskeletal events of GLUT4 trafficking were targets of ET‐1. Both insulin and hyperosmotic stress signaling to Cbl were impaired by ET‐1. Also, plasma membrane PIP2 and cortical actin levels were reduced in cells exposed to ET‐1. Exogenous PIP2, but not PI 3,4,5‐bisphosphate, restored actin structure, Cbl activation, and GLUT4 translocation. These data show that ET‐1‐induced PIP2/actin disruption impairs GLUT4 trafficking elicited by insulin and hyperosmolarity. In addition to showing for the first time the important role of PIP2‐regulated cytoskeletal events in GLUT4 regulation by stimuli other than insulin, these studies reveal a novel function of PIP2/actin structure in signal transduction. J. Cell. Biochem. 97: 849–856, 2006. © 2005 Wiley‐Liss, Inc.
Deregulation of cyclin‐dependent kinase 2 activity correlates with UVC‐induced apoptosis in Chinese hamster ovary cells
Authors: Liao Chu‐Bin , Chang Yu‐Ching , Kao Chien‐Wen , Taniga Ezhilan Sathyapriya , Li Hsun , Tzang Bor‐Show , Liu Yin‐Chang 
Published: October 2005

AbstractProgression through the cell cycle relies on the activities of cyclin‐dependent kinases (Cdk), which in turn are modulated by inhibitory proteins such as p21(waf1/cip1) that are induced when genomic damage occurs. In this study, we show that exposure of normal mammalian cells, such as NIH3T3 fibroblasts, to UVC (25 J/m2, at 254 nm) induces the expression of p21 without causing significant apoptosis, whereas similar treatment of Chinese hamster ovary (CHO‐K1) cells with UVC causes apoptosis without inducing p21. The absence of p21 in UV‐irradiated CHO‐K1 cells is accompanied by the deregulation of Cdk2 activity. The elevation of Cdk2 activity correlates with the increase of UV‐induced apoptosis, which can be suppressed by small‐molecule Cdk2 inhibitors such as roscovitine and pyrrolidine dithiocarbamate. The results of this study suggest that the deregulation of Cdk2 activity may be critical to UV‐induced apoptosis in CHO‐K1 cells. J. Cell. Biochem. 97: 824–835, 2006. © 2005 Wiley‐Liss, Inc.
Optimal pulse durations for the treatment of leg telangiectasias with a neodymium YAG laser
Authors: Parlette Eric C. , Groff William F. , Kinshella Matthew J. , Domankevitz Yacov , O'Neill Jennifer , Ross E. Victor 
Published: October 2005

AbstractBackgroundLeg veins can be effectively treated with lasers. However, the optimal pulse duration for small leg veins has not been established in human studies with a Nd:YAG laser.ObjectivesThe purpose of this study was to investigate a range of pulse durations to determine an optimal pulse duration for clearance of leg veins.Study Design/Materials and MethodsAfter mapping and photo documentation of the leg veins to be treated, a variable pulse duration Neodymium:Yttrium Aluminum Garnet (Nd:YAG) laser (3–100 milliseconds) was used in a single test site session. Pulse durations of 3, 20, 40, 60, 80, and 100 milliseconds were used. At the 3‐week follow‐up, the optimal pulse duration was defined as that pulse duration which resulted in the most complete clearance of vessels with the least side effects. Up to 20 vessels were then treated using the established “optimal” pulse duration. Final evaluation was at 16 weeks after the initial visit. Three blinded observers rated the percent of vessels completely cleared based on initial and final photographs.ResultsEighteen patients completed the study. Fluence thresholds for immediate vessel changes varied depending on spot size and vessel diameter, with larger fluences required for smaller spot sizes and smaller vessels. Shorter pulse durations (≤20 milliseconds) were associated with occasional spot sized purpura and spot sized post‐inflammatory hyperpigmentation. Longer pulse durations (40–60 milliseconds) achieved superior vessel elimination with less post‐inflammatory hyperpigmentation. With a single laser treatment, 71% of the treated vessels cleared.ConclusionsCompared to shorter pulses (<20 milliseconds), longer pulses may provide gentler heating of the vessel and a greater ratio of contraction to thrombosis. Lasers Surg. Med. 38:98–105, 2006. © 2005 Wiley‐Liss, Inc.
The use of genomic microarrays to study chromosomal abnormalities in mental retardation
Authors: Mao Rong , Pevsner Jonathan 
Published: October 2005

AbstractMental retardation affects 2 to 3% of the US population. It is defined by broad criteria, including significantly subaverage intelligence, onset by age 18, and impaired function in a group of adaptive skills. A myriad of genetic and environmental causes have been described, but for approximately half of individuals diagnosed with mental retardation the molecular basis remains unknown. Genomic microarrays, also called array comparative genomic hybridization (array CGH), represent one of several novel technologies that allow the detection of chromosomal abnormalities, such as microdeletions and microduplications, in a rapid, high throughput fashion from genomic DNA samples. In one early application of this technology, genomic microarrays have been used to characterize the extent of chromosomal changes in a group of patients diagnosed with one particular type of disorder that causes mental retardation, such as deletion 1p36 syndrome. In another application, DNA samples from individuals with idiopathic mental retardation have been assayed to scan the entire genome in attempts to identify chromosomal changes. Genomic microarrays offer both a genome‐wide perspective of chromosomal aberrations as well as higher resolution (to the level of approximately one megabase) compared to alternative available technologies. © 2005 Wiley‐Liss, Inc. MRDD Research Reviews 2005;11:279–285.
Mental retardation genes in drosophila: New approaches to understanding and treating developmental brain disorders
Authors: Restifo Linda L. 
Published: October 2005

AbstractDrosophila melanogasteris emerging as a valuable genetic model system for the study of mental retardation (MR). MR genes are remarkably similar between humans and fruit flies. Cognitive behavioral assays can detect reductions in learning and memory in flies with mutations in MR genes. Neuroanatomical methods, including some at single‐neuron resolution, are helping to reveal the cellular bases of faulty brain development caused by MR gene mutations.Drosophila fragile X mental retardation 1(dfmr1) is the fly counterpart of the human gene whose malfunction causes fragile X syndrome. Research on the fly gene is leading the field in molecular mechanisms of the gene product's biological function and in pharmacological rescue of brain and behavioral phenotypes. Future work holds the promise of using genetic pathway analysis and primary neuronal culture methods inDrosophilaas tools for drug discovery for a wide range of MR and related disorders. © 2005 Wiley‐Liss, Inc. MRDD Research Reviews 2005;11:286–294.
Measuring behavior in genetic disorders of mental retardation
Authors: Hodapp Robert M. , Dykens Elisabeth M. 
Published: October 2005

AbstractAs researchers have examined the so‐called “behavioral phenotypes” of different genetic mental retardation conditions, the measurement of behavior becomes increasingly important. From earlier, more global examinations of noteworthy behaviors or profiles, recent researchers have moved from reliance on a single, all‐encompassing questionnaire to more multimethod, multireporter approaches. This paper summarizes strengths and weaknesses in utilizing parent‐report questionnaires and checklists; psychiatric nosology and specific psychiatric questionnaires; observational studies; reports from individuals with mental retardation themselves; profile analyses of psychometric test and subtest scores; and “grouping” analyses of items (factor analysis) and people (cluster analysis). Although we advocate a mixture of approaches to behavioral assessment, in future work researchers will require more theoretically driven methods for studying behavior, greater acknowledgment that the child's behavior is simply one event in ongoing interactions–transactions with other people, and more attention to age‐related changes in behavioral phenotypes. © 2005 Wiley‐Liss, Inc. MRDD Research Reviews 2005;11:340–346.
The contribution of novel brain imaging techniques to understanding the neurobiology of mental retardation and developmental disabilities
Authors: Gothelf Doron , Furfaro Joyce A. , Penniman Lauren C. , Glover Gary H. , Reiss Allan L. 
Published: October 2005

AbstractStudying the biological mechanisms underlying mental retardation and developmental disabilities (MR/DD) is a very complex task. This is due to the wide heterogeneity of etiologies and pathways that lead to MR/DD. Breakthroughs in genetics and molecular biology and the development of sophisticated brain imaging techniques during the last decades have facilitated the emergence of a field called Behavioral Neurogenetics. Behavioral Neurogenetics focuses on studying genetic diseases with known etiologies that are manifested by unique cognitive and behavioral phenotypes. In this review, we describe the principles of magnetic resonance imaging (MRI) techniques, including structural MRI, functional MRI, and diffusion tensor imaging (DTI), and how they are implemented in the study of Williams (WS), velocardiofacial (VCFS), and fragile X (FXS) syndromes. From WS we learn that dorsal stream abnormalities can be associated with visuospatial deficits; VCFS is a model for exploring the molecular and brain pathways that lead to psychiatric disorders for which subjects with MR/DD are at increased risk; and finally, findings from multimodal imaging techniques show that aberrant frontal–striatal connections are implicated in the executive function and attentional deficits of subjects with FXS. By deciphering the molecular pathways and brain structure and function associated with cognitive deficits, we will gain a better understanding of the pathophysiology of MR/DD, which will eventually make possible more specific treatments for this population. © 2005 Wiley‐Liss, Inc. MRDD Research Reviews 2005;11:331–339.
Rheology and curing characteristics of epoxy–clay nanocomposites
Authors: Mohan TP , Ramesh Kumar M , Velmurugan R 
Published: October 2005

AbstractDiglycidyl ethers of bisphenol‐A (DGEBA) epoxy resin, filled separately with organoclay (OC) and unmodified clay (UC), were synthesized at room temperature and at high temperature (80 °C) by mechanical shear mixing. The room temperature curing (RTC) and high temperature curing (HTC) were carried out with the addition of triethylene tetramine (TETA) and diaminodiphenylmethane (DDM) curing agents respectively. The OC used was alkyl ammonium modified montmorillonite (MMT) and the UC was Na+‐MMT. X‐ray diffraction (XRD) and transmission electron microscopy (TEM) were used to study the structure and morphology of the nanocomposites. The influence of OC and UC particles on rheology and curing characteristics was studied. The rate of increase in viscosity was higher for OC‐filled resin than that of the UC‐filled resin. The curing study showed that the amine ions of the OC aided the polymerization process and favoured the curing at low temperature over the curing of unfilled epoxy resin. The tensile properties were enhanced for epoxy filled with OC particles rather than those filled with UC particles. Copyright © 2005 Society of Chemical Industry
Dispersion polymerization of methyl methacrylate in supercritical carbon dioxide using a silicone‐containing fluoroacrylate stabilizer
Authors: Deniz Sennur , Baran Nil , Akgün Mesut , Uzun I Nimet , Dinçer Salih 
Published: October 2005

AbstractFree radical dispersion polymerization of methyl methacrylate (MMA) was carried out in supercritical carbon dioxide (scCO2) using poly{(heptadecafluorodecyl acrylate)‐co‐3‐[tris(trimethylsilyloxy)silyl]propyl methacrylate} (p(HDFDA‐co‐SiMA)) as stabilizer. Dry, fine powdered spherical poly(methyl methacrylate) (pMMA) particles with well‐defined sizes were produced. The resulting high yield of spherical and relatively uniform micron‐size pMMA particles was formed utilizing various amounts of p(HDFDA‐co‐SiMA) random copolymer. The particle diameter was shown to be dependent on the weight percent of the stabilizer added to the system. The effects of varying the concentration of stabilizer (1–7 wt%), reaction time (4–12 h) and pressure (15–35 MPa) upon the polymerization yield, molar mass and morphology of pMMA were investigated. Copyright © 2005 Society of Chemical Industry
Properties of poly(ethylene terephthalate)–poly(ethylene naphthalene 2,6‐dicarboxylate) blends with montmorillonite clay
Authors: Sanchez‐Solis Antonio , Garcia‐Rejon Andres , Estrada Mirna , Martinez‐Richa Antonio , Sanchez Guadalupe , Manero Octavio 
Published: October 2005

AbstractThe production and properties of blends of poly(ethylene terephthalate) (PET) and poly(ethylene naphthalene 2,6‐dicarboxylate) (PEN) with three modified clays are reported. Octadecylammonium chloride and maleic anhydride (MAH) are used to modify the surface of the montmorillonite–Na+ clay particles (clay–Na+) to produce clay–C18 and clay–MAH, respectively, before they are mixed with the PET/PEN system. The transesterification degree, hydrophobicity and the effect of the clays on the mechanical, rheological and thermal properties are analysed. The PET–PEN/clay–C18 system does not show any improvements in the mechanical properties, which is attributed to poor exfoliation. On the other hand, in the PET–PEN/clay–MAH blends, the modified clay restricts crystallization of the matrix, as evidenced in the low value of the crystallization enthalpy. The process‐induced PET–PEN transesterification reaction is affected by the clay particles. Clay–C18 induces the largest proportion of naphthalate–ethylene–terephthalate (NET) blocks, as opposed to clay–Na+ which renders the lowest proportion. The clay readily incorporates in the bulk polymer, but receding contact‐angle measurements reveal a small influence of the particles on the surface properties of the sample. The clay–Na+ blend shows a predominant solid‐like behaviour, as evidenced by the magnitude of the storage modulus in the low‐frequency range, which reflects a high entanglement density and a substantial degree of polymer–particle interactions. Copyright © 2005 Society of Chemical Industry
Methacryloxyethyl phosphate‐grafted expanded polytetrafluoroethylene membranes for biomedical applications
Authors: Wentrup‐Byrne Edeline , Grøndahl Lisbeth , Suzuki Shuko 
Published: October 2005

AbstractExpanded polytetrafluoroethylene (ePTFE) membranes were modified by graft copolymerization with methacryloxyethyl phosphate (MOEP) in methanol and 2‐butanone (methyl ethyl ketone (MEK)) at ambient temperature using gamma irradiation. The effect of dose rate (0.46 and 4.6 kGy h−1), monomer concentration (1–40 %) and solvent were studied and the modified membranes were characterized by weight increase, X‐ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). XPS was used to determine the % degree of surface coverage using the CF (ePTFE membrane) and the CC (MOEP graft copolymer) peaks. Grafting yield, as well as surface coverage, were found to increase with increasing monomer concentration and were significantly higher for samples grafted in MEK than in methanol solution. SEM images showed distinctly different surface morphologies for the membranes grafted in methanol (smooth) and MEK (globular), hence indicating phase separation of the homopolymer in MEK. We propose that in our system, the non‐solvent properties of MEK for the homopolymer play a more important role than solvent chain transfer reactions in determining grafting outcomes. Copyright © 2005 Society of Chemical Industry
Effects of α‐form or β‐form nuclei on polymorphic crystalline morphology of poly(butylene adipate)
Authors: Wu Ming Chien , Woo EM 
Published: October 2005

AbstractThe effects of α‐form and β‐form nuclei on polymorphic morphology of poly(butylene adipate) (PBA) upon recrystallization from the molten state up to various Tmax values were examined by differential scanning calorimetry (DSC), wide‐angle X‐ray diffraction (WAXD) and polarized light microscopy (PLM). In this study, PBA with complex melting and polymorphism behaviour was used as a model for examining different types and extents of residual nuclei. As the PBA initially containing the sole α‐crystal was brought to a molten state of various Tmax, the extents of trace α‐form crystal nuclei varied and were dependent on Tmax. Furthermore, it did not matter whether, initially, the PBA contained α‐ or β‐form crystals (or both) because only a single type of α‐nuclei could be left upon treatment to the molten liquid state at Tmax. Therefore, only the α‐crystal in PBA had ‘memory capacity’ in the molten liquid state while the β‐crystal did not. This was so because the latter had been completely transformed into the solid state prior to being heated into a liquid. PBA crystallized before α‐nuclei could be packed into α‐crystal, regardless of the crystallization temperature (Tc). For recrystallization from molten PBA without any nuclei, the crystalline polymorphism was correspondingly influenced by Tc. Copyright © 2005 Society of Chemical Industry
The ligand effect in Ti‐mediated living radical styrene polymerizations initiated by epoxide radical ring opening. 2. Scorpionate and half‐sandwich LTiCl3 complexes
Authors: Asandei Alexandru D. , Moran Isaac W. 
Published: October 2005

AbstractThe ligand effect and the reaction conditions for the living radical polymerization of styrene initiated by epoxide radical ring opening was investigated in a series of piano‐stool, Ti(IV) scorpionate and, half‐sandwich metallocenes (LTiCl3; L = Tp, Cp*, Ind and Cp, where Tp = hydrotris(pyrazol‐1‐ylborato), Cp* = pentamethylcyclopentadienyl, Ind = indenyl and Cp = cyclopentadienyl). The polymerization is mediated by the reversible termination of the growing chains with Ti(III) species derived from Zn reduction of parent Ti(IV) derivatives. A poor performance was observed for TpTiCl3 because of probable over‐reduction. The strong electron donating effect of Cp* accounts for a strong CTi chain end bond and consequently, a living‐like process is observed only at T > 110 °C. However, both Ind and Cp ligands provide a linear dependence of Mn on conversion and narrow polydispersity over a wide range of experimental conditions. Investigation of the effect of temperature and reagent ratios generates an optimum for epoxide/CpTiCl3/Zn = 1/2/4 at 70–90 °C. On the basis of a combination of steric and electronic properties, the ligands rank as Cp ≥ Ind ≫ Cp* ≫ Tp. This trend is different from coordination polymerization, and in conjunction with our previous results on Cp2TiCl2, further supports a radical mechanism. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6039–6047, 2005
Force measurements using capillary instabilities
Authors: Steiner Ullrich 
Published: October 2005

AbstractThis article reviews some recent experimental studies on film instabilities. Since surface instabilities of planar films are driven by destabilizing interfacial pressures, the patterns that form in thin films are a signature of these interfacial forces. The direct correspondence of pattern selection and the underlying destabilizing pressures provides a way to quantitatively determine these interface potentials. This principle is documented for three different film destabilization mechanisms: van der Waals forces, forces caused by an applied electric field, and forces that arise from the confinement of thermal molecular motion in the film. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3395–3405, 2005
Orthogonal surface‐grafted polymer gradients: A versatile combinatorial platform
Authors: Bhat Rajendra R. , Tomlinson Michael R. , Genzer Jan 
Published: October 2005

AbstractOrthogonal polymer brush gradients are assemblies of surface‐anchored macromolecules, in which two material properties of the grafted chains (e.g., grafting density, molecular weight) vary independently in orthogonal directions. Here, we describe the formation and applications of two such orthogonal assemblies, involving: (1) molecular weight and grafting density (MW/σ) gradients of a given polymer and (2) molecular weight gradients (MW1/MW2), of two different polymers. Each point on orthogonal gradient substrate represents a unique combination of the two surface properties being varied, thus facilitating systematic investigation of a phenomenon that depends on the two said properties. We illustrate this point by employing orthogonal structures to study systematically: (1) formation of polymer brush‐nanoparticle composite assemblies, (2) protein adsorption and cell adhesion, and (3) chain conformations in tethered diblock copolymers exposed to selective solvents. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3384–3394, 2005