bluuebunny/crossref_metadata_2025_split huggingface dataset:
Signalling responses linked to betulinic acid‐induced apoptosis are antagonized by MEK inhibitor U0126 in adherent or 3D spheroid melanoma irrespective of p53 status
Authors: Rieber Manuel , Rieber Mary Strasberg 
Published: September 2005

AbstractMEK1/2 inhibitors like U0126 can potentiate or antagonize the antitumor activity of cytotoxic agents such as cisplatin, paclitaxel or vinblastine, depending on the drug or the target cells. We now investigated whether U0126, differentially regulates melanoma signaling in response to UV radiation or betulinic acid, a drug lethal against melanoma. This report shows that U0126 inhibits early response (ERK) kinase activation and cyclin A expression in wt p53 C8161 melanoma exposed to either UV radiation or betulinic acid. However, U0126 does not protect from UV damage, but counteracts betulinic acid‐mediated apoptosis in the same cells. Protection from the latter drug by joint treatment with U0126 was also evident in wt p53 MelJuso melanoma and mutant p53 WM164 melanoma. The latter cells were the most responsive to betulinic acid, showing a selective decline in the cdk4 protein, without a comparable change in other key cell cycle proteins like cdc2, cdk2, cdk7 or cyclin A, prior to apoptosis‐associated PARP fragmentation. Laser scanning cytometry also showed that betulinic acid induced a significant increase in chromatin condensation in WM164 melanoma irrespective of whether they were in adherent form or as multicellular spheroids. All these betulinic acid‐induced changes were counteracted by U0126. Our data show for the first time that (a) cdk4 protein is an early target of betulinic acid‐induced apoptosis and (b) unrestricted ERK signaling favours betulinic acid‐induced apoptosis, but this is counteracted by U0126, partly through counteracting chromatin condensation and restoring Akt activation decreased by betulinic acid treatment. © 2005 Wiley‐Liss, Inc.
Epidermal growth factor receptor and angiogenesis: Opportunities for combined anticancer strategies
Authors: van Cruijsen Hester , Giaccone Giuseppe , Hoekman Klaas 
Published: September 2005

AbstractTumor‐induced angiogenesis is essential for malignant growth. This mini review focuses on the role of vascular endothelial growth factor (VEGF) and epidermal growth factor (EGF) and their receptors in this process, and the rationale to combine inhibitors of these growth factors as anticancer therapy. Concomitantly, targeting the VEGF(R) and the EGF(R) signaling pathway may circumvent the problem of acquired resistance to EGFR inhibitors. By targeting both pathways, the antiangiogenic effect may be more pronounced, which may lead to greater antitumor activity. Preliminary efficacy data from clinical trials encourage further exploration of this combined anticancer strategy. © 2005 Wiley‐Liss, Inc.
Atorvastatin stimulates the production of osteoprotegerin by human osteoblasts
Authors: Viereck Volker , Gründker Carsten , Blaschke Sabine , Frosch Karl‐Heinz , Schoppet Michael , Emons Günter , Hofbauer Lorenz C. 
Published: September 2005

AbstractRecently, HMG‐CoA reductase inhibitors (statins), potent inhibitors of cholesterol biosynthesis, have been linked to protective effects on bone metabolism. Because of their widespread use, prevention of bone loss and fractures would be a desirable side effect. However, the mechanisms how statins may affect bone metabolism are poorly defined. Here, we evaluated the effect of atorvastatin on osteoblastic production of receptor activator of nuclear factor‐κB ligand (RANKL) and osteoprotegerin (OPG), cytokines that are essential for osteoclast cell biology. While RANKL enhances osteoclast formation and activation, thereby, promoting bone loss, OPG acts as a soluble decoy receptor and antagonizes the effects of RANKL. In primary human osteoblasts (hOB), atorvastatin increased OPG mRNA levels and protein secretion by hOB by up to three fold in a dose‐dependent manner with a maximum effect at 10−6 M (P < 0.001). Time course experiments indicated a time‐dependent stimulatory effect of atorvastatin on OPG mRNA levels after 24 h and on OPG protein secretion after 48–72 h (P < 0.001). Treatment of hOB with substrates of cholesterol biosynthesis that are downstream of the HMG‐CoA reductase reaction (mevalonate, geranylgeranyl pyrophosphate) reversed atorvastatin‐induced enhancement of OPG production. Of note, atorvastatin abrogated the inhibitory effect of glucocorticoids on OPG production. Treatment of hOB with atorvastatin enhanced the expression of osteoblastic differentiation markers, alkaline phosphatase and osteocalcin. In summary, our data suggest that atorvastatin enhances osteoblastic differentiation and production of OPG. This may contribute to the bone‐sparing effects of statins. © 2005 Wiley‐Liss, Inc.
Morphology and Thermal Properties of MCPA6/ABS by in situ Polymerization of ε‐Caprolactam
Authors: Hou Lianlong , Yang Guisheng 
Published: September 2005

AbstractSummary: In this work, blends of monomer casting polyamide 6 (MCPA6) and acrylonitrile‐butadiene‐styrene (ABS) were successfully prepared by in situ polymerization via the application of ε‐caprolactam as a reactive solvent. The morphology and thermal properties of MCPA6/ABS were investigated by means of wide angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM), respectively. The domain sizes of the ABS phase in MCPA6/ABS blends were much finer than those in corresponding polyamide 6 (PA6)/ABS blends prepared by simple melt blending. With an increased amount of ABS in MCPA6, the melt enthalpy (ΔHf), the rate of crystallization (Tc) and the degree of crystallinity (Xc(DSC)) of MCPA6 in MCPA6/ABS blends were all decreased. The degree of supercooling (ΔTd) showed a contrary trend. However, the melting temperatures of these blends were almost unchanged. All the results could be attributed to in situ polymerization and the hydrolysis reaction of ABS that occurred during the polymerization process. Furthermore, WAXD results showed that only α‐form crystals existed in the MCPA6/ABS blends, despite the ABS content and heat treatment.SEM micrograph of the fractured surface of an MCPA6/ABS blend with an ABS content of 20 wt.‐% (×10 000).imageSEM micrograph of the fractured surface of an MCPA6/ABS blend with an ABS content of 20 wt.‐% (×10 000).
Triggering the Thermosensitive Properties of Hydrophobically Modified Poly(N‐isopropylacrylamide) by Complexation with Cyclodextrin Polymers
Authors: Wintgens Véronique , Charles Michaël , Allouache Farid , Amiel Catherine 
Published: September 2005

AbstractSummary: Hydrophobically modified poly(N‐isopropylacrylamide) (PNIPAM) containing either an adamantyl or a dodecyl group were prepared and characterized. Self‐association in aqueous solutions was evidenced by fluorescence measurements using pyrene as a probe. The lower critical solution temperatures (LCST) were determined from cloud point measurements. They strongly depended on the hydrophobic group and the substitution level. The association between hydrophobically modified PNIPAM and β‐cyclodextrin (monomers and polymers) was investigated by cloud point and viscosity measurements. The presence of β‐cyclodextrin monomers generally shifted the LCST to a higher temperature, the complexation increasing the solubility of PNIPAM chains. β‐Cyclodextrin polymers mixed with hydrophobically modified PNIPAM generated supramolecular assemblies. This was evidenced by viscosity measurements of the mixtures at temperatures lower than the LCST. Moreover, depending on the substitution level of the PNIPAM, the LCST was increased (1% hydrophobic groups) or decreased (4% hydrophobic groups) by more than 10 °C upon β‐cyclodextrin polymer addition.Transmission variations of different mixtures of PNIPAM‐C12 with cyclodextrin compounds vs temperature.imageTransmission variations of different mixtures of PNIPAM‐C12 with cyclodextrin compounds vs temperature.
Rod‐Like Silicate‐Epoxy Nanocomposites
Authors: Lu Hongbin , Shen Hongbin , Song Zhenlun , Shing Katherine S. , Tao Wei , Nutt Steven 
Published: September 2005

AbstractSummary: Epoxy nanocomposites containing rod‐like silicate (attapulgite) were prepared using a simple organic modification to the nanorods. The modification led to effective interfacial adhesion between the ceramic nanorods and the epoxy resin and hence good load transfer. Scanning electron microscopy examination revealed a uniform dispersion of nanorods in the epoxy resin. Compared to the neat resin, nanocomposites with 7.47 vol.‐% nanorods exhibited an increase in the (rubbery state) storage modulus of 122.5%. In addition, the nanocomposites exhibited improved dimensional stability both above and below the Tg.Storage modulus of the neat resin and nanocomposites.magnified imageStorage modulus of the neat resin and nanocomposites.
RAFT Polymerization of Pentafluorophenyl Methacrylate: Preparation of Reactive Linear Diblock Copolymers
Authors: Eberhardt Marc , Théato Patrick 
Published: September 2005

AbstractSummary: Reversible addition fragmentation chain transfer (RAFT) polymerization of pentafluorophenyl methacrylate (PFMA) was carried out in the presence of cumyldithiobenzoate and 4‐cyano‐4‐((thiobenzoyl)sulfanyl)pentanoic acid, respectively. These chain transfer agents with 2,2′‐azoisobutyronitrile (AIBN) as initiator yielded the active ester polymer poly(PFMA) with $\overline M _{\rm n}$ up to 17 000 g · mol−1 and low polydispersity index ($\overline M _{\rm w} /\overline M _{\rm n}$ < 1.2). Kinetic analysis using 19F NMR spectroscopy and gel permeation chromatography (GPC) measurements showed controlled polymerization behavior for both chain transfer agents. Successful preparation of linear diblock copolymers consisting of an active ester block and methyl methacrylate, N‐acryloylmorpholine, or N,N‐diethylacrylamide, respectively, could be demonstrated. These polymers could easily react with amines in a polymer analogous reaction to form multifunctional polymers.
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Formation of o‐Phenylenediamine Oligomers and their Self‐Assembly into One‐Dimensional Structures in Aqueous Medium
Authors: Sun Xuping , Dong Shaojun , Wang Erkang 
Published: September 2005

AbstractSummary: Uniform one‐dimensional (1D) structures of o‐phenylenediamine (oPD) oligomers are obtained by direct mix of AgNO3 and oPD aqueous solutions at room temperature. The formation of the 1D structures involves two stages: (1) oxidation of oPD by AgNO3, yielding individual oPD oligomers; and (2) self‐assembly of the oligomers, forming the 1D structures. Upon decreasing medium pH, the 1D structures can break‐apart to form individual oligomers, or vice versa. It is also found that both the concentration and molar ratio of reactants can influence the morphology of the structures thus formed.Schematic illustration of the formation mechanism of 1D structures from oPD and AgNO3, and energy‐dispersed spectrum of the precipitate.magnified imageSchematic illustration of the formation mechanism of 1D structures from oPD and AgNO3, and energy‐dispersed spectrum of the precipitate.
Genetic heterogeneity in patients with pantothenate kinase–associated neurodegeneration and classic magnetic resonance imaging eye‐of‐the‐tiger pattern
Authors: Valentino Paola , Annesi Grazia , Cirò Candiano Innocenza C. , Annesi Ferdinanda , Civitelli Donatella , Tarantino Patrizia , Naso Francesco , Spadafora Patrizia , Carrideo Sara , De Marco Elvira V. , Consoli Domenico , Zappia Mario , Gambardella Antonio , Quattrone Aldo 
Published: September 2005

AbstractWe performed a detailed molecular study in two unrelated families with pantothenate kinase–associated neurodegeneration (PKAN) and the specific magnetic resonance imaging (MRI) eye‐of‐the‐tiger pattern. In the first family with classic PKAN, linkage analysis using polymorphic markers from the PANK2 region ruled out linkage with this locus, and no mutation of the PANK2 gene was found. In the second family with atypical PKAN, we identified a novel homozygous C‐to‐T transition at nucleotide 1069 of the PANK2 gene, which resulted in an arginine to tryptophane substitution at codon 357. As far as we are aware, this is the first case of classic PKAN with the specific MRI eye‐of‐the‐tiger pattern not carrying a PANK2 mutation. Therefore, the present observation reinforces the notion of the phenotypic and genetic heterogeneity in PKAN. © 2005 Movement Disorder Society
Orthostatic tremor during modification of standing
Authors: Spiegel Jörg , Krick Christoph , Fuss Gerhard , Sood Dania , Becker Georg , Dillmann Ulrich 
Published: September 2005

AbstractPrimary orthostatic tremor (OT) occurs only during standing. We studied whether modification of the condition standing influences OT. In seven patients with OT, surface EMG was recorded from both tibialis anterior and gastrocnemius muscles during two maneuvers: relief, whereby the patient was gradually lifted by a crane, and tilting, whereby the patient was tilted by a tilting table to positions of 90° (upright standing), 45° (diagonal position), and 0° (lying position). We determined the parameters tremor frequency, tremor intensity, coherence, and phase shift between the different muscles. Relief did not influence OT. In contrast, tilting modified significantly tremor intensity and phase shifts; tremor frequencies and coherences were not influenced. We chose both these maneuvers because of their different impact on the standing condition: relief modifies the factors afferent input and muscle forcing but not the factor postural set, whereas tilting modifies all three factors. The fact that tilting modifies OT, whereas relief does not, suggests an important role of postural set in OT generation. Afferent input and muscle forcing seem to play less important role. © 2005 Movement Disorder Society
Frequency analysis and clinical characterization of different types of spinocerebellar ataxia in Serbian patients
Authors: Dragašević Nataša T. , Čuljković Biljana , Klein Christine , Ristić Aleksandar , Keckarević Milica , Topisirović Ivan , Vukosavić Slobodanka , Svetel Marina , Kock Norman , Stefanova Elka , Romac Stanka , Kostić Vladimir S. 
Published: September 2005

AbstractThe relative frequencies of different spinocerebellar ataxias (SCAs) vary widely among different ethnic groups, presumably due to a founder effect. We investigated the relative prevalence of SCA1–3, 6–8, 12, 17; dentate–rubro–pallidoluysian atrophy; and Friedreich's ataxia (FRDA) in Serbian patients with adult‐onset (>20 years of age) hereditary and sporadic SCAs, and compared clinical features of patients with genetically confirmed SCAs. A total of 108 patients from 54 families (38 apparently dominant [ADCA] and 16 apparently recessive) with adult‐onset hereditary ataxia and 75 apparently sporadic patients were assessed. Of 38 families with ADCA, 13 (34%) were positive for an expansion in an SCA1 and 5 families (13%) for an expansion in an SCA2 allele. In 20 families (53%), no expansions have been identified in any of the analyzed genes. Gaze palsy, spasticity, and hyperreflexia were significantly more common in SCA1, whereas slow saccades, hypotonia, hyporeflexia, and dystonia prevailed in SCA2 patients. Among the 16 families with an apparently recessive mode of ataxia inheritance, 4 (25%) were identified as having the FRDA mutation. Ataxia‐causing mutations were identified in 8 (10.6%) of patients with apparently sporadic adult‐onset ataxia. © 2005 Movement Disorder Society
Reply: Akinetic crisis, acute akinesia, neuroleptic malignant‐like syndrome, Parkinsonism–hyperpyrexia syndrome, and malignant syndrome are the same entity and are often independent of treatment withdrawal
Authors: Kipps Christopher M. , Fung Victor S.C. , Grattan‐Smith Padraic , deMoore Gregory M. , Morris John G.L. 
Published: September 2005

AbstractThe original letter to which this reply refers was published in Movement Disorders Mov Disord (2005)DOI 10.1002/mds.20689.
Akinetic crisis, acute akinesia, neuroleptic malignant‐like syndrome, Parkinsonism–hyperpyrexia syndrome, and malignant syndrome are the same entity and are often independent of treatment withdrawal
Authors: Thomas Astrid , Onofrj Marco 
Published: September 2005

AbstractA reply to this letter has been published in Movement Disorders Mov Disord (2005)DOI 10.1002/mds.20688.
Magnetic stimulation using a triple‐stimulation technique in patients with multifocal neuropathy without conduction block
Authors: Attarian Shahram , Azulay Jean‐Philippe , Verschueren Annie , Pouget Jean 
Published: September 2005

AbstractIt has been suggested previously that multifocal motor neuropathy (MMN) without conduction block (CB) or other features of demyelination is axonal in nature. Conventional transcranial magnetic stimulation (TMS) and the triple‐stimulation technique (TST) performed on 10 MMN patients without CB revealed a proximal focal CB in 4 patients. In 3 other patients, the amplitude ratio obtained in response to conventional TMS was abnormally low, but the area ratio was normal. The TST amplitude ratio and area ratio were normal in these 3 patients. This pattern suggested the occurrence of temporal dispersion without CB. The occurrence of temporal dispersion or CB was associated with a relatively satisfactory response to intravenous immunoglobulins. These findings suggest that some forms of MMN previously thought to be axonal are in fact proximal variants of MMN with CB. Muscle Nerve, 2005
Conformational variation and crystalline phase transformation of low syndiotactic polypropylene films in stretched and stress‐relaxed states
Authors: Zhang Xiu‐Qin , Zhao Ying , Shi Hai‐Feng , Dong Xia , Wang Du‐Jin , Han Charles C. , Xu Duan‐Fu 
Published: September 2005

AbstractLow syndiotactic polypropylene (sPP; rrrr = 80%) films were isothermally crystallized at 0 °C (sample S0) and 90 °C (sample S90) for 65 h, respectively. Fourier transform infrared spectroscopy, differential scanning calorimetry, and wide‐angle X‐ray diffraction were used to characterize the structure transformation and orientation behavior of samples S0 and S90 at both stretched and stress‐relaxed states. It was found that stretching (λ = 0–700%) induces the transformation of the chain conformation from helical to trans‐planar form for both S0 and S90 films. The stretched S0 and S90 samples show well oriented trans‐planar chains as well as partially retained helices. Simultaneously, crystalline phase transformation occurs during the stretching and relaxing processes of the investigated sPP samples, i.e., stable form I crystals can be transformed into metastable form III or mesophase by stretching samples, and vice versa. For stretched S0 sample, form III with trans‐planar conformation, which generally exists in highly stretched sPP, cannot be observed, even at higher strains. For sample S90, however, stretching might induce the formation of both the form III crystals and mesophase with trans‐planar chains; releasing the tension, form III again gets converted into trans‐planar mesophase and form I crystals. In the stretched and stress‐relaxed states of samples S0 and S90, the difference of the delicate orientation behavior and relative content of chain conformation and crystalline form can be attributed to the different heat‐treating methods of the low syndiotacticity sPP. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2924–2936, 2005
Phase separation behavior of aqueous solutions of a thermoresponsive polymer
Authors: Matsuda Yasuhiro , Miyazaki Yuji , Sugihara Shinji , Aoshima Sadahito , Saito Kazuya , Sato Takahiro 
Published: September 2005

AbstractCloud‐point and binodal curves of the LCST type were obtained for aqueous solutions of a thermoresponsive polymer, poly [2‐(2‐ethoxy)ethoxyethyl vinyl ether], poly(EOEOVE). The cloud‐point curve obtained was very flat except in a dilute region, that is the cloud‐point temperature was insensitive to the polymer concentration, resembling the cloud‐point curve for aqueous solutions of poly(N‐isopropylacrylamide). On the other hand, the binodal curve obtained was parabolic, and located within the two‐phase region of the cloud‐point curve. Accompanied with the phase separation, a sharp endothermic peak was observed in a region including the cloud‐point and binodal temperatures. The reciprocal of the osmotic compressibility ∂Π/∂c obtained by sedimentation equilibrium indicated that water changes from a good to poor solvent for poly(EOEOVE) with increasing temperature. Analyzing the ∂Π/∂c data by a thermodynamic perturbation theory, we determined the interchain interaction parameters, the hard‐core diameter d and the depth ε of the square‐well potential. Theoretical binodal and endothermic curves calculated by the perturbation theory using the estimated interaction parameters reproduced experimental ones semiquantitatively, but the theoretical binodal disagreed with the experimental flat cloud‐point curve. The disagreement at high concentrations was in the opposite direction to that expected from the sample polydispersity in the molecular weight. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2937–2949, 2005
Local deformation in photo‐crosslinked polymer blends monitored by Mach‐Zehnder interferometry
Authors: Inoue Kyosuke , Komatsu Satonori , Trinh Xuan‐Anh , Norisuye Tomohisa , Tran‐Cong‐Miyata Qui 
Published: September 2005

AbstractLocal deformation of a polymer mixture crosslinked by irradiation with ultraviolet light was in situ monitored by using a Mach‐Zehnder interferometer. In combination with the refractive index data obtained from independent measurements, the deformation in the nanometer scales of the crosslinked blends was calculated by using the difference in optical path length of the blend measured before and after irradiation. Upon varying the crosslink density of the blend by changing the light intensity, it was found that the local deformation well correlates with the crosslink density obtained from the reaction kinetics experiments. Furthermore, the strain relaxation of the blends was also monitored in situ and analyzed after irradiation over different time intervals. The results obtained in this study reveal the possibility of monitoring the nanometer‐scale deformation in polymers during radiation curing. These data also provide important information on the correlations between the irradiation‐induced elastic strain and the resulting morphology of reacting polymer blends. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2898–2913, 2005
Crystal structure of a purine/pyrimidine phosphoribosyltransferase‐related protein from Thermus thermophilus HB8
Authors: Rehse Peter H. , Tahirov Tahir H. 
Published: September 2005

AbstractAdenine phosphoribosyltransferase (APRTase) is a widely distributed enzyme involved in the salvage of adenine to form an adenine nucleotide. We crystallized and determined the X‐ray crystallographic structure of a purine/pyrimidine phosphoribosyltransferase‐related protein from the thermophilic bacterium, Thermus thermophilus HB8. The crystal space group was C2 with unit cell dimensions of a = 167.42 Å, b = 61.41 Å, c = 102.39 Å, β = 94.0°. Initial phases were determined to 2.6 Å using the multiple wavelength anomalous dispersion method and selenomethionine substituted protein (Se‐MAD), and refined using a 1.9 Å “native” data set. The asymmetric unit contains two pairs of identical dimers, each related by noncrystallographic two‐fold symmetry. The fifth monomer forms a similar dimer across a crystallographic two‐fold axis. These dimers appear to be the biological unit with both monomers contributing to an unusual highly charged arginine‐rich bridge region separating the two active sites. Comparison with distantly related APRTases reveal similarities and differences of the active site. Proteins 2005. © 2005 Wiley‐Liss, Inc.