bluuebunny/crossref_metadata_2025_split huggingface dataset:
Production of P‐glycoprotein from the MDR1 upstream promoter is insufficient to affect the response to first‐line chemotherapy in advanced breast cancer
Authors: Raguz Selina , Randle Rebecca A. , Sharpe Eva R. , Foekens John A. , Sieuwerts Anieta M. , Meijer‐van Gelder Marion E. , Melo Junia V. , Higgins Christopher F. , Yagüe Ernesto 
Published: October 2007

AbstractMultidrug resistance, the phenomenon by which cells treated with a drug become resistant to the cytotoxic effect of a variety of other structurally and functionally unrelated drugs, is often associated with the expression of P‐glycoprotein, an efflux membrane pump coded by the MDR1 (ABCB1) gene. Transcription from MDR1 can start at 2 promoters: a well‐characterized downstream promoter and an as yet uncharacterized upstream promoter (USP). We have previously determined that the USP is activated in some drug‐resistant cell lines, in primary breast tumors and in metastatic epithelial cells isolated from the lymph nodes of breast cancer patients. In this study, we report the cloning and characterization of the MDR1 USP and studied its association with chemotherapy response in breast cancer patients. Deletion analysis indicated that a nearby endogenous retroviral long terminal repeat is not responsible for promoter activation, and that the region within the first 400 nucleotides upstream from the transcription start point contained all the elements necessary for promoter activity in drug‐resistant cells. We identified an element recognized by the transcription factor NF‐IL6 (activated upon interleukin‐6 exposure) which is necessary for promoter activity in drug‐resistant cells and plays a role in the activation of the promoter in response to interleukin‐6 in breast cancer MCF‐7 cells. Although transcripts from this promoter are associated with translating polyribosomes, their low abundance makes the amount of synthesized P‐glycoprotein insufficient to affect the response to first‐line chemotherapy in patients with advanced breast cancer. © 2007 Wiley‐Liss, Inc.
Morphoregulation by acetylcholinesterase in fibroblasts and astrocytes
Authors: Anderson Alexandra A. , Ushakov Dmitry S. , Ferenczi Michael A. , Mori Ryoichi , Martin Paul , Saffell Jane L. 
Published: October 2007

AbstractAcetylcholinesterase (AChE) terminates neurotransmission at cholinergic synapses by hydrolysing acetylcholine, but also has non‐enzymatic morphoregulatory effects on neurons such as stimulation of neurite outgrowth. It is widely expressed outside the nervous system, but its function in non‐neuronal cells is unclear. Here we have investigated the distribution and function of AChE in fibroblasts and astrocytes. We show that these cells express high levels of AChE protein that co‐migrates with recombinant AChE but contains little catalytic activity. Fibroblasts express transcripts encoding the synaptic AChE‐T isoform and its membrane anchoring peptide PRiMA‐I. AChE is strikingly distributed in arcs, rings and patches at the leading edge of spreading and migrating fibroblasts and astrocytes, close to the cell–substratum interface, and in neuronal growth cones. During in vivo healing of mouse skin, AChE becomes highly expressed in re‐epithelialising epidermal keratinocytes 1 day after wounding. AChE appears to be functionally important for polarised cell migration, since an AChE antibody reduces substratum adhesion of fibroblasts, and slows wound healing in vitro as effectively as a β1‐integrin antibody. Moreover, elevation of AChE expression increases fibroblast wound healing independently of catalytic activity. Interestingly, AChE surface patches precisely co‐localise with amyloid precursor protein and the extracellular matrix protein perlecan, but not focal adhesions or α‐dystroglycan, and contain a high concentration of tyrosine phosphorylated proteins in spreading cells. These findings suggest that cell surface AChE, possibly in a novel signalling complex containing APP and perlecan, contributes to a generalised mechanism for polarised membrane protrusion and migration in all adherent cells. J. Cell. Physiol. 215: 82–100, 2008. © 2007 Wiley‐Liss, Inc.
Cutting two graphs simultaneously
Authors: Patel Viresh 
Published: October 2007

AbstractConsider two graphs, $G_1$ and $G_2$, on the same vertex set V, with $|V|= n$ and $G_{i}$ having $m_{i}$ edges for $i = 1,2$. We give a simple algorithm that partitions V into sets A and B such that $e_{{G}_{1}}(A,B) \geq m_{1}/2$ and $e_{G_{2}}(A,B) \geq m_{2}/2 - \Delta (G_{2})/2$. We also show, using a probabilistic method, that if $G_1$ and $G_2$ belong to certain classes of graphs, (for instance, if $G_1$ and $G_2$ both have a density of at least 2/, or if $G_1$ and $G_2$ are both regular of degree at most $(n/16) - 6$ with n sufficiently large) then we can find a partition of V into sets A and B such that $e_{G_{i}}(A,B) \geq m_{i}/2$ for $i = 1,2$. © 2007 Wiley Periodicals, Inc. J Graph Theory 57: 19–32, 2008
A case for a downwasting mountain glacier during Termination I, Verçenik valley, northeastern Turkey
Authors: Akçar N. , Yavuz V. , Ivy‐Ochs S. , Kubik P. W. , Vardar M. , Schlüchter C. 
Published: October 2007

AbstractField evidence of palaeoglacial records in the Verçenik valley in the Eastern Black Sea Mountains was examined and 19 samples for surface exposure dating with cosmogenic 10Be were collected with the aim of increasing knowledge on the amplitude and frequency of palaeoglacier advances in Anatolia. Glacial erosional features were mapped and the flow directions of the palaeoglaciers were determined. The Verçenik palaeoglacier advanced before 26.1 k ± 1.2 k yr. The Last Glacial Maximum (LGM) advance continued until 18.8 k ±1.0 k yr. The Verçenik palaeoglacier collapsed during Termination I. After 17.7 k ± 0.8 k yr there was no more ice in the main valley. The Verçenik palaeoglacier most probably then separated into five small glaciers that were restricted to the tributary valleys. Among these, the Hemşin palaeoglacier completed its recession around 15.7 k ± 0.8 k yr. On the basis of glacial erosion features, a Lateglacial glacier advance can be identified. Evidence of the Little Ice Age advance appears to be absent. The results from this valley system seem to be consistent with the first results from the adjacent Kavron valley and with the Anatolian LGM palaeoclimate, the sea surface temperature minima in the western Mediterranean, the deposition of red clay layers in the Black Sea and deposition of the Heinrich‐1 layer in the North Atlantic. Copyright © 2007 John Wiley & Sons, Ltd.
Microtextural analysis of a glacially ‘deformed’ bedrock: implications for inheritance of preferred clast orientations in diamictons
Authors: Phillips Emrys , Auton Clive 
Published: October 2007

AbstractAlthough analysis of clast macrofabrics has been used to differentiate between different types of glacial diamictons and to determine palaeo‐ice flow directions, no account appears to have been made of preferred clast orientations inherited from the parental source material. Clast macrofabrics in tills are typically interpreted as having developed in response to an imposed subglacial deformation and as such provide a link between the sedimentary record and glacier dynamics. They rely on the assumption that any preferred clast orientation is a result of deformation/flow. The results of the micromorphological study of the Langholm Till exposed at North Corbelly near Dumfries (southwestern Scotland) clearly demonstrate that bedrock structure can influence clast orientation (macrofabric) within diamictons. In the lower part of the till, the orientation of elongate clasts preserves the geometry of the tectonic cleavage present within the underlying bedrock. The intensity of this steeply inclined, ‘inherited’ clast fabric decreases upward through the till, to be replaced by a more complex pattern of successive generations of clast microfabrics developed in response to deformation/flow. These results indicate potential limitations of applying clast macrofabric or microfabric analysis in isolation to establish till genesis or palaeo ice‐flow directions. Consequently, due account should be made of other glacial palaeo‐environmental and ice flow indicators, as well as rockhead depth and morphology in relation to the selection of fabric measurements sites. © British Geological Survey/Natural Environment Research Council copyright 2007. Reproduced with the permission of BGS/NERC. Published by John Wiley & Sons, Ltd.
Genetics of posttraumatic stress disorder: Review and recommendations for future studies
Authors: Koenen Karestan C. 
Published: October 2007

AbstractPosttraumatic stress disorder (PTSD) is common and debilitating. Posttraumatic stress disorder is moderately heritable; however, the role of genetic factors in PTSD etiology has been largely neglected by trauma researchers. The goal of this study is to motivate trauma researchers to reflect on the role genetic variation may play in vulnerability and resilience following trauma exposure. Evidence from family, twin, and molecular genetic studies for genetic influences on PTSD is reviewed. Recommendations for future studies are presented with emphasis on study design and assessment issues particular to the field of trauma and PTSD. Clinical implications of PTSD genetic studies are discussed.
The relationship between childhood support and later emergence of PTSD
Authors: Lauterbach Dean , Koch Ellen I. , Porter Katherine 
Published: October 2007

AbstractThe authors examine the relationship between three sources of social support (maternal, paternal, and peer) and the development of posttraumatic stress disorder (PTSD). This study utilized data from the National Comorbidity Survey (NCS), a large (N = 5,877) nationally representative population survey. Persons with and without a lifetime history of PTSD and those with and without a history of trauma exposure were compared on levels of social support received prior to age 15. Persons with a history of PTSD reported that they received less maternal, paternal, and peer support as children than those without PTSD. Importantly, persons who developed PTSD after the age of 17 reported lower levels of early childhood support from their fathers.*This NCS was supported through the following grants awarded to Ronald Kessler: R01 MH/DA46376 and R01 MH49098 (NIMH), supplement to R01 MH/DA46376, (NIDA) and 90135190 (W.T. Grant Foundation).
Considerations in treatment integrity: Implications and recommendations for PTSD research
Authors: Barber Jacques P. , Triffleman Elisa , Marmar Charles 
Published: October 2007

AbstractIn this article, the authors address the rationale for and uses of treatment integrity measurement in psychotherapy research, focusing on therapists' adherence and competence in trauma and posttraumatic stress disorder treatment research. The following issues are examined: (a) distinctions between adherence monitoring, performed contemporaneously with ongoing study treatments, and adherence evaluation, and the implications for outcomes analysis; (b) simultaneous measurement of adherence and competence; (c) selection of sessions for adherence/competence assessment and the need for concurrent outcome measurement, and (d) the association between therapist adherence, competence, alliance and treatment outcome. Recommendations regarding common problems in the implementation of adherence and competence measurement are made throughout. The article concludes with a summary of steps and considerations in decision‐making with regard to treatment integrity.
An asperity‐based mathematical model for the boundary lubrication of nominally flat metallic contacts
Authors: Zhang H. , Chang L. 
Published: October 2007

AbstractA mathematical model is presented to study the boundary lubrication of nominally flat metallic contacts. It is developed on the basis of the Greenwood–Williamson model, incorporating key aspects of boundary lubrication in asperity contacts. Four variables are used to describe the asperity contact, including micro‐contact area, pressure, interfacial shear stress and flash temperature. Furthermore, three probability variables are used to define the interfacial state of an asperity junction that may be covered by the lubricant/additive molecules adsorbed on the surface, protected by a chemical film, or in direct contact with no boundary protection. Governing equations for the seven asperity‐level variables are derived based on first‐principle considerations of the asperity deformation, frictional heating and kinetics of boundary films. These equations are solved simultaneously to determine the asperity interfacial state and calculate the contact variables. The asperity‐level solutions are then integrated to formulate the boundary‐lubrication model at the system level with statistical descriptions of the surfaces. Results are presented and analysed including system friction behaviour, surface separation and real area of contact, and the state of boundary lubrication for various operating conditions and surface roughness. Some potential applications of the model are described. The model and the modelling concepts may provide a framework for future boundary‐lubrication analysis, incorporating research advances in contact mechanics, tribochemistry and other related fields. Copyright © 2007 John Wiley & Sons, Ltd.
Sugar‐Responsive Fluorescent Nanospheres
Authors: Zenkl Gunter , Mayr Torsten , Klimant Ingo 
Published: October 2007

AbstractSugar‐responsive polymer fluorescent nanospheres based on N‐isopropylacrylamide and phenylboronic acid were prepared by precipitation polymerization with an average size of 380 nm. The particles swell in the presence of sugar, and the rate and extent of this swelling was measured with distance‐dependent fluorescence resonance energy transfer. We present a direct link between the ratio of the intensities of the fluorophores and the particle size. Depending on the kind of sugar and the sugar concentration, different swelling kinetics and equilibrium sizes are observed. With this approach we can obtain insight into complex structure changes with simple fluorescent measurements.magnified image
The influence of artificial aging on the microstructure, mechanical properties, corrosion, and environmental cracking susceptibility of a 7075 friction‐stir‐weld
Authors: Paglia C. S. , Jata K. V. , Buchheit R. G. 
Published: October 2007

AbstractThe influence of overaging to the T7451 temper on the microstructure, the mechanical properties, and the corrosion susceptibility of friction‐stir‐welded 7075 aluminum alloy was investigated by means of transmission electron microscope (TEM), SEM investigations, constant extension rate tests (CERT), alternate immersion tests, and potentiodynamic scans. The overaging that occurs during welding within the heat‐affected zones of the friction‐stir‐welded 7075‐O tempered plates promotes a slight formation of intragranular and grain boundary precipitates and increases the mechanical as well as the corrosion resistance properties as compared to the T7451 welded plates. The “double” overaging treatment, consisting of the T7451 temper and the thermal transient experienced by the heat‐affected zones of the 7075‐T7451 welded plates, increases the size of the intragranular and the grain boundary precipitates as well as the precipitate‐free zones. These facts decrease the mechanical and corrosion properties of the 7075‐T7451 weld. The T7451 thermal treatment applied after the welding of the 7075‐O plates promotes the high presence of small precipitates and reduces the size of the precipitate‐free zones. This fact increases the general corrosion resistance, but decreases the mechanical properties. Therefore, the corrosion as well as the mechanical properties are greatly correlated with minute changes in the microstructure, which can arise by short‐term heat exposure as for instance during welding. It was also found that the environmental susceptibility measured by means of CERTs may be influenced by “solution‐strengthening” corrosion mechanisms which increase the strain. This fact is present in weld microzones particularly susceptible to corrosion.
Corrosion resistance of three austenitic stainless steels for biomedical applications
Authors: Terada M. , Antunes R. A. , Padilha A. F. , Costa I. 
Published: October 2007

AbstractThe resistance to localized corrosion of three austenitic stainless steels (SS), specifically the ASTM F‐138 which is widely used in several biomedical applications, the DIN 1.4460 high N, and the DIN 1.4970 was investigated in this study by electrochemical techniques including potentiodynamic polarization and electrochemical impedance spectroscopy measurements in a phosphate‐buffered solution. The DIN 1.4460 high N and the DIN 1.4970 were tested in this study for the reason they do not form any ferromagnetic phases, such as delta‐ferrite or martensite, although these phases might be formed in the first type of SS. Although all the three SS tested are prone to localized attack, the DIN 1.4460 high N presented the highest corrosion resistance among the SS followed by the DIN 1.4970 and finally the ASTM F‐138. Shallower and smaller pits were formed on the DIN 1.4970 compared to the ASTM F‐138 SS.
Evaluation of NDT methods for detection of prestressing steel damage at post‐tensioned concrete structures
Authors: Mietz J. , Fischer J. 
Published: October 2007

AbstractFor an assessment of the risk potential of existing structures, where in the case of prestressing steel damage the load‐bearing capacity could be significantly affected, non‐destructive testing techniques which enable reliable evaluation of the condition of the prestressing steels are of utmost importance. During the demolition of a post‐tensioned concrete bridge in Berlin where damage of prestressing wires due to hydrogen‐induced stress corrosion cracking were found in former investigations, parts of the girders of the bridge superstructure could be taken out. After non‐destructive investigations by means of two testing techniques based on magnetic leakage flux measurement and one technique based on electromagnetic resonance measurement, subsequent removal of the concrete cover up to the ducts, opening the ducts and evaluation of the prestressing steels allowed a verification of the results obtained by the NDT methods. From the results it can be concluded that areas with fractures of several wires can be detected by the two techniques based on magnetic leakage flux measurement.
Physico‐Mechanical Properties and the TVOC Emission Factor of Gypsum Particleboards Manufactured with Pinus Massoniana and Eucalyptus Sp.
Authors: Kim Sumin , Kim Jin‐A. , An Jae‐Yoon , Kim Hee‐Soo , Kim Hyun‐Joong , Deng Yuhe , Feng Qian , Luo Jiayan 
Published: October 2007

AbstractThe effect of wood species on the TVOC emission factor and the physico‐mechanical properties of GPBs is investigated. Of the two wood species, the water absorption was higher for the GPBs made using Eucalyptus sp. than for those using Pinus massoniana. The Eucalyptus sp. GPBs pressed at room temperature, 40 and 60 °C all demonstrated higher moisture absorption than commercial GPBs. The TVOC emission factor decreased with increasing press temperature, especially for Eucalyptus sp. but remained under ‘excellent’ grade as defined by the KACA. From these results, GPB with higher content of wood particles should be considered for the replacement of wood‐based panels such as particleboard and medium density fiberboard (MDF).magnified image
Polymeric One‐Dimensional Photonic Crystals by Continuous Coextrusion
Authors: Kazmierczak Tomasz , Song Hyunmin , Hiltner Anne , Baer Eric 
Published: October 2007

AbstractIt is shown that narrowband one‐dimensional photonic crystals can be fabricated from polymeric materials using laboratory scale layer‐multiplying coextrusion technology. The tuning of the photonic bandgap is demonstrated with films that selectively filter different regions of the visible electromagnetic spectrum. The layer uniformity of the photonic crystals is evaluated by comparing the measured UV‐vis transmission spectra with model simulations, and is independently confirmed with atomic force microscopy. Assemblies of alternating polystyrene and poly(methyl methacrylate) layers exhibit a narrow reflection band with close to 100% reflection in good agreement with the prediction for uniform layers. The flexibility of the process is demonstrated by the fabrication of elastomeric one‐dimensional photonic crystals. It is anticipated that this technology will enable the rapid and facile realization of new polymeric optical devices.magnified image
Osmolarity at early culture stage affects development and expression of apoptosis related genes (bax‐α and bcl‐xl) in pre‐implantation porcine NT embryos
Authors: Hwang In‐Sun , Park Mi‐Rung , Moon Hyo‐Jin , Shim Joo‐Hyun , Kim Dong‐Hoon , Yang Byoung‐Chul , Ko Yeoung‐Gyu , Yang Boh‐Suk , Cheong Hee‐Tae , Im Gi‐Sun 
Published: October 2007

AbstractThis study examined whether high osmolarity of culture medium at the early culture stage affects development and expression of apoptosis related genes (Bax‐α and Bcl‐xl) of porcine nuclear transfer (NT) and in vitro fertilization (IVF) embryos. NT and IVF embryos were divided into three groups and the basic medium was PZM‐3 (260–270 mOsmol, control group). The control group of embryos was cultured in PZM‐3 for whole culture period. Other two groups of embryos were cultured in a modified PZM‐3 with 0.05 M sucrose (300–320 mOsmol, sucrose group) or increased NaCl to 138 mM (300–320 mOsmol, NaCl group) for the first 2 days, and then cultured in PZM‐3 for 4 days. NT embryos cultured in NaCl group showed a significantly higher developmental rate to the blastocyst stage with a decreased apoptosis rate compared to the control (P < 0.05). There was no difference in blastocyst formation and apoptosis incidence among the three culture treatments for IVF‐derived embryos. Bax‐α mRNA expression was significantly higher in the control than sucrose or NaCl group for both NT and IVF embryos (P < 0.05). Moreover, the relative abundance of Bax‐α/Bcl‐xl was higher in the control than the treatment groups. These results indicate that the higher osmolarity at the early embryonic stage of porcine NT and IVF embryos can improve the in vitro development with reduced apoptosis through regulating the Bax‐α/Bcl‐xl gene expression. Mol. Reprod. Dev. 75: 464–471, 2008. © 2007 Wiley‐Liss, Inc.