bluuebunny/crossref_metadata_2025_split huggingface dataset:
Change of HER‐2/neu status in a subset of distant metastases from breast carcinomas
Authors: Regitnig Peter , Schippinger Walter , Lindbauer Mareike , Samonigg Hellmut , Lax Sigurd F 
Published: July 2004

AbstractIt is assumed that HER‐2/neu status remains consistent in breast carcinoma during metastatic spread, but in most previous studies primary tumours were compared with concurrent regional lymph node metastases. The present study investigated 31 breast carcinomas and their corresponding lymph node and distant metastases for HER‐2/neu status by immunohistochemistry (HercepTest™) and fluorescence in situ hybridization (FISH) (PathVysion™). In 14 cases, serum HER‐2/neu (SHER‐2) was measured sequentially using the Bayer Immuno 1™ HER‐2/neu assay. Comparing HER‐2/neu immunohistochemistry of primary tumours and distant metastases case by case, increased HER‐2/neu expression was found in the distant metastases in 15 cases (48.4%), three (9.7%) of which showed an increase from score 0 to score 3+. In contrast, lymph node metastases showed the same HER‐2/neu expression as the primary tumours, confirmed by FISH. Two cases, which showed HER‐2/neu score 3+ and HER‐2/neu amplification in the primary tumours, revealed increased SHER‐2 levels above 50 ng/ml at the first measurement. Five of the 14 cases (36%) showed an increase of SHER‐2 above 50 ng/ml towards the end of the patients' life. On the basis of these results, there is evidence that in a subset of breast carcinomas, HER‐2/neu amplification and overexpression occur de novo in distant metastases at a late disease stage. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Increased expression of matrix metalloproteinases in the murine zymosan‐induced multiple organ dysfunction syndrome
Authors: Volman TJH , Goris RJA , Lomme RMLM , DeGroot J , Verhofstad Albert AJ , Hendriks T 
Published: July 2004

AbstractMatrix metalloproteinases (MMPs) have been implicated as mediators of tissue damage in several inflammatory diseases. Since the multiple organ dysfunction syndrome (MODS) is thought to result from systemic inflammation, overactivation of MMPs could contribute to the organ damage observed. The expression and activity of several MMPs were studied in a murine model for MODS. Sixty mice were given an aseptic intraperitoneal injection of lipopolysaccharide, followed, after 6 days, by zymosan. At days 2, 5, 8, 12, and 16 after the injection of zymosan, the liver, lungs, spleen, and kidneys were collected from groups of mice for either RNA extraction, gelatinase zymography and collagenase (MMP‐1 and ‐13) assays (six mice per time point), or immunohistochemistry (three mice per time point). A group of nine mice did not receive zymosan and acted as controls. The expression of MMP‐2 mRNA in zymosan‐treated mice was strongly up‐regulated in liver tissue only. For MMP‐9, this was the case in all organs examined. Quantitative gelatin zymography demonstrated the near complete absence of any gelatinase activity in tissues from control mice. However, in the liver, lungs, and especially the spleen of zymosan‐treated animals, significantly increased activity of proform and active MMP‐2 and ‐9 was observed with time. Overall, MMP‐1 and ‐13 activities were very low in all samples from the liver and lungs. In the spleen, however, high levels of MMP‐1 and ‐13 were observed in zymosan‐treated animals. Immunohistochemical staining for MMP‐2 was detected in the liver and spleen, but not in lung and kidney tissue of zymosan‐treated animals. Staining for MMP‐9 could be detected in liver, lung, and spleen tissues of zymosan‐treated mice. For both MMPs, staining appeared to be limited to phagocytes. In conclusion, the data suggest a role for MMPs, especially MMP‐9, in the pathogenesis of MODS. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Metastatic dissemination of human malignant oral keratinocyte cell lines following orthotopic transplantation reflects response to TGF‐β 1
Authors: Prime SS , Eveson JW , Stone AM , Huntley SP , Davies M , Paterson IC , Robinson CM 
Published: July 2004

AbstractThis study examined the behaviour of nine human malignant oral keratinocyte cell lines following orthotopic transplantation to the floor of the mouth of athymic mice. Tumourigenesis, local spread, and metastatic dissemination were correlated with known cellular responses to transforming growth factor‐β 1 (TGF‐β 1). Six of nine cell lines were tumourigenic; four of these cell lines showed local spread which was characterized by vascular and bone invasion. Metastatic spread was uncommon, with only 9% of animals with primary tumours developing metastases and these were almost exclusively found in the regional lymph nodes; there was one pulmonary metastasis and no liver deposits. Tumour cell behaviour did not reflect the clinical stage of the original tumours. Cell lines that were resistant to TGF‐β 1‐induced growth inhibition were more likely to form primary tumours, exhibit local spread, and metastasize than cells that were growth‐inhibited by the ligand. The data demonstrate that tumourigenicity and tumour behaviour in this orthotopic mouse model varied between cell lines and that the pattern of local invasion and metastasis was similar to that seen in human oral cancer. Furthermore, cell lines that were refractory to the growth inhibitory effects of TGF‐β 1 behaved more aggressively than cells that underwent ligand‐induced cell‐cycle arrest. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Improved prediction for N‐termini of α‐helices using empirical information
Authors: Wilson Claire L. , Boardman Paul E. , Doig Andrew J. , Hubbard Simon J. 
Published: July 2004

AbstractThe prediction of the secondary structure of proteins from their amino acid sequences remains a key component of many approaches to the protein folding problem. The most abundant form of regular secondary structure in proteins is the α‐helix, in which specific residue preferences exist at the N‐terminal locations. Propensities derived from these observed amino acid frequencies in the Protein Data Bank (PDB) database correlate well with experimental free energies measured for residues at different N‐terminal positions in alanine‐based peptides. We report a novel method to exploit this data to improve protein secondary structure prediction through identification of the correct N‐terminal sequences in α‐helices, based on existing popular methods for secondary structure prediction. With this algorithm, the number of correctly predicted α‐helix start positions was improved from 30% to 38%, while the overall prediction accuracy (Q3) remained the same, using cross‐validated testing. Although the algorithm was developed and tested on multiple sequence alignment–based secondary structure predictions, it was also able to improve the predictions of start locations by methods that use single sequences to make their predictions. Furthermore, the residue frequencies at N‐terminal positions of the improved predictions better reflect those seen at the N‐terminal positions of α‐helices in proteins. This has implications for areas such as comparative modeling, where a more accurate prediction of the N‐terminal regions of α‐helices should benefit attempts to model adjacent loop regions. The algorithm is available as a Web tool, located at http://rocky.bms.umist.ac.uk/elephant. Proteins 2004. © 2004 Wiley‐Liss, Inc.
The coupling of structural fluctuations to hydride transfer in dihydrofolate reductase
Authors: Thorpe Ian F. , Brooks Charles L. 
Published: July 2004

AbstractThe energy barrier for hydride transfer in wild‐type G121V and G121S variants of Escherichia coli dihydrofolate reductase (DHFR) fluctuates in a time‐dependent manner. This fluctuation may be attributed to structural changes in the protein that modulate the site of chemistry. Despite being far from the active site, mutations at position 121 of DHFR reduce the hydride transfer rate of the enzyme. This occurrence has been suggested to arise from modifications to the conformational ensemble of the protein. We elucidate the effects of the G121S and G121V mutations on the hydride transfer barrier by identifying structural changes in the protein that correlate with lowered barriers. The effect of these structural parameters on the hydride transfer barrier may be rationalized by simple considerations of the geometric constraints of the hydride transfer reaction. Fluctuations of these properties are associated with specific backbone dihedral angles of residues within the Methione‐20 (M20) loop. The dihedral angle preferences are mediated by interactions with the region of the enzyme in the vicinity of residue 121 and are translated into distinct ligand conformations. We predict mutations within the M20 loop that may alter the conformational space explored by DHFR. Such mutational changes are anticipated to adjust the hydride transfer efficacy of DHFR by modifying equilibrium distributions of hydride transfer barriers found in the enzyme. Proteins 2004. © 2004 Wiley‐Liss, Inc.
Acetamiprid resistance and cross‐resistance in the diamondback moth, Plutella xylostella
Authors: Ninsin Kodwo D 
Published: July 2004

AbstractA 110‐fold acetamiprid‐resistant Plutella xylostella (L) strain was established after four selection experiments (in five generations) on a 9.5‐fold resistant colony in the laboratory. The resistant strain did not show cross‐resistance to chlorfluazuron or Bacillus thuringiensis subsp kurstaki Berliner, but displayed low resistance to cartap and phenthoate. Copyright © 2004 Society of Chemical Industry
Electron transport and magnetoresistance in ferromagnetic nanostructures
Authors: Giordano N. , Çetin B. 
Published: July 2004

AbstractRecent studies of very narrow Ni wires have shown that the resistance of a wire containing domain walls can be smaller than for a sample without walls; i.e., the domain wall resistance is effectively negative. In this paper we investigate the corresponding behavior of permalloy wires. For these wires the resistance decreases markedly during magnetization reversal. We show that this decrease is due to a combination of coherent rotation and a negative domain wall resistance. We are able to separate these two effects, and extract an estimate for the resistance of an individual domain wall. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Surface dynamics of the layered ruthenate Ca1.9Sr0.1RuO4
Authors: Moore Rob G. , Zhang Jiandi , Kalinin S. V. , Ismail  , Baddorf A. P. , Jin R. , Mandrus D. G. , Plummer E. W. 
Published: July 2004

AbstractThe strong coupling between electronic, lattice, orbital, and spin degrees of freedom in transition metal oxides implies that the symmetry breaking at the surface of these materials should lead to a rich surface phase diagram and interesting new physics. Here we investigate the surface phases of the Ca2–xSrxRuO4 system that (in bulk) can be tuned from a Mott insulator (x = 0) to a p‐wave superconductor (x = 2) without changing the electron count. This system therefore displays a “bandwidth controlled” metal‐insulator transition. Electronic and structural properties of these surfaces are studied by variable temperature High Resolution Electron Energy Loss Spectroscopy (HREELS) and Low Energy Electron Diffraction (LEED). It is found that broken symmetry on the Sr2RuO4 surface results in the rotation of RuO4 octahedra relative to bulk positions along the c‐axis, changing the relative in‐plane Ru‐O bond length and shifting the surface phonon energies. The substitution of Ca ions in Sr2RuO4 crystals results in a rotation plus a tilt of the RuO6 octahedra creating a Mott‐insulator phase. In particular, Ca1.9Sr0.1RuO4 exhibits a Mott transition below 154 K in bulk single crystals. However, with HREELS, we observed phonon and conductivity dynamics at the surface of Ca1.9Sr0.1RuO4 crystals below ∼130 K, indicating a lower surface Mott transition temperature than in the bulk. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A spectroscopic view of electron–phonon coupling at metal surfaces
Authors: Tang S.‐J. , Shi Junren , Wu Biao , Sprunger P. T. , Yang W. L. , Brouet V. , Zhou X. J. , Hussain Z. , Shen Z.‐X. , Zhang Zhenyu , Plummer E. W. 
Published: July 2004

AbstractIt is now possible to extract from high‐resolution angle‐resolved photoemission data the Eliashberg function α2F(ω) for electron‐phonon coupling (EPC). At the same time, first‐principles calculations of the EPC for surface states are appearing in the literature presenting an exquisite picture of the origin of the Eliashberg function. The advances in this field will be illustrated with new data from surface states on two faces of berylium and a direct comparisin to theory for Be(0001). (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anomalous thickness dispersion of unoccupied states in the Cu/Ni/Cu(100) metallic quantum well system
Authors: Danese A. G. , Yao H. , Arena D. A. , Hochstrasser M. , Tobin J. G. , Bartynski R. A. 
Published: July 2004

AbstractWe present photoemission and inverse photoemission measurements of the occupied and unoccupied electronic states of the Cu/Ni/Cu(100) system. While the occupied levels of the Cu overlayer display the usual upward dispersion with increasing overlayer thickness, the unoccupied states exhibit an anomalous downward dispersion similar to that seen for the Cu/Ni(100) system. While the anomalous dispersion depends quantitatively on Ni film thickness, and hence on in‐plane strain, the qualitative behavior of downward dispersing features is seen for all Ni thicknesses studied. Our results suggest that the origin of the anomalous dispersion is tied to the Cu‐overlayer/Ni‐film interface. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Seasonal and diurnal variations of total attenuation measured with the ITALSAT satellite at Spino d'Adda at 18.7, 39.6 and 49.5 GHz
Authors: Riva Carlo 
Published: July 2004

AbstractThe ITALSAT satellite experiment started in January 1991 and ended in January 2001, permitting an extensive program of propagation measurements at 18.7, 39.6 and 49.5 GHz. In these frequency bands, up‐ and down‐links experience severe signal attenuation due to meteorological effects such as those due to gas (oxygen and water vapour), clouds, turbulence and, especially, rain. The propagation measurement campaigns aim mainly at assessing and at modelling the appropriate fade margin compensating propagation attenuation in the design of satellite communication systems. This margin depends significantly on the season and on the time of the day, due to variations of meteorological conditions. This paper reports the results obtained from copolar signal measurements carried out at the Earth station of Spino d'Adda, near Milano (North Italy), at the three frequencies during 7 years (from 1994 to 2000). The measured cumulative distribution functions of total attenuation are compared to ITU‐R models' prediction. Moreover the statistics conditioned to single months of the year, seasons and 4 h contiguous periods of the day are also shown. These statistics can be useful for telecommunication systems whose service quality and design must be matched to the season of the year or the time of the day. Copyright © 2004 John Wiley & Sons, Ltd.
Die Stahlverbundbrücke über die Müglitz im Zuge der Autobahn Dresden–Prag – Entwurf und Ausführung
Authors: Reintjes Karl‐Heinz , Schreiber Oliver 
Published: July 2004

AbstractDie im Zuge des Neubaus der A17 ausgeführte Müglitztalbrücke durchquert mit einer Länge von 310 m den in der Nähe von Dresden liegenden Ort Dohna und überquert dabei eine Bahnstrecke, eine Staatsstraße und den Fluß Müglitz. Aufgrund der das Stadtbild prägenden Lage der Brücke wurden in der Entwurfsphase umfangreiche Untersuchungen aufgestellt, um die gestalterisch richtige und technisch zweckmäßige Lösung für die gegebene Situation zu finden. Gewählt und ausgeführt wurde eine Balkenbrücke in Stahlverbundbauweise mit den Stützweiten 45 – 55 – 55 – 55 – 55 – 45 m und getrennten Überbauten. Je Überbau sind zwei dicht geschweißte Stahlkästen als Hauptträger angeordnet. Um der Brücke eine differenzierte Gliederung zu geben, sind die Hauptträger mit Vouten und ausgestellten Steifenkästen in den Lagerungsbereichen ausgebildet. Bei der Gestaltung der Stützen wurden diese Merkmale aufgegriffen und durch aufgeweitete Köpfe und einen achteckigen Querschnitt fortgeführt. Hauptaugenmerk wurde auf eine einfache Fertigung und auf eine unproblematische Montage des Stahlbaus mit möglichst wenigen Schweißarbeiten auf der Baustelle gelegt. Es wird über den Entwurf und die Ausführung berichtet. Außerdem wird über Erfahrungen berichtet, die bei anderen Bauwerken mit dichten Kastenträgern gesammelt werden konnten.
Modal combination method for earthquake‐resistant design of tall structures to multidimensional excitations
Authors: Li Hong‐Nan , Sun Li , Song Gangbing 
Published: July 2004

AbstractThis paper presents a modal combination method for earthquake‐resistant design of structures to multidimensional seismic excitations. With the assumption that an earthquake is a stationary random vibration, the correlation among the input components is considered in the proposed method. The relationship coefficients between the translational component and rotational component is then derived in the frequency domain. The combination method of response spectrum for structural response to multidimensional earthquakes is proposed based on the random vibration theory. With the help of the derived modal correlation coefficients, the formulation for structural response to the two‐dimensional earthquake excitations can be obtained. Numerical examples demonstrate the effectiveness and high precision of the proposed methods. Copyright © 2004 John Wiley & Sons, Ltd.
Neuropeptides and the social brain: potential rodent models of autism
Authors: Lim Miranda M. , Bielsky Isadora F. , Young Larry J. 
Published: July 2004

AbstractConducting basic scientific research on a complex psychiatric disorder, such as autism, is a challenging prospect. It is difficult to dissociate the fundamental neurological and psychological processes that are disturbed in autism and, therefore, it is a challenge to discover accurate and reliable animal models of the disease. Because of their role in animal models of social processing and social bonding, the neuropeptides oxytocin and vasopressin are strong candidates for dysregulation in autism. In this review, we discuss the current animal models which have investigated oxytocin and vasopressin systems in the brain and their effects on social behavior. For example, mice lacking the oxytocin gene have profound deficits in social processing and social recognition, as do rats lacking vasopressin or mice lacking the vasopressin V1a receptor (V1aR). In another rodent model, monogamous prairie voles are highly social and form strong pair bonds with their mates. Pair bonds can be facilitated or disrupted by perturbing the oxytocin and vasopressin systems. Non‐monogamous vole species that do not pair bond have different oxytocin and V1aR distribution patterns in the brain than monogamous vole species. Potential ties from these rodent models to the human autistic condition are then discussed. Given the hallmark disturbances in social function, the study of animal models of social behavior may provide novel therapeutic targets for the treatment of autism.
In vivo and in vitro effects of homocysteine on Na+,K+‐ATPase activity in parietal, prefrontal and cingulate cortex of young rats
Authors: Matté Cristiane , Monteiro Siomara C. , Calcagnotto Thiago , Bavaresco Caren S. , Netto Carlos Alexandre , Wyse Angela T.S. 
Published: July 2004

AbstractIn the present study we determined the effect of chronic administration of homocysteine on Na+,K+‐ATPase activity in synaptic membranes from parietal, prefrontal and cingulate cortex of young rats. We also studied the in vitro effect of homocysteine on this enzyme activity and on some oxidative stress parameters, namely thiobarbituric acid‐reactive substances (TBA‐RS) and total radical‐trapping antioxidant potential (TRAP) in the same cerebral structures. For the in vivo studies, we induced elevated levels of homocysteine in blood (500 μM), comparable to those of human homocystinuria, and in brain (60 nmol/g wet tissue) of young rats by injecting subcutaneously homocysteine (0.3–0.6 μmol/g of body weight) twice a day at 8 h intervals from the 6th to the 28th postpartum day. Controls received saline in the same volumes. Rats were killed 12 h after the last injection. Chronic administration of homocysteine significantly decreased (50%) Na+,K+‐ATPase activity in parietal, increased (36%) in prefrontal and did not alter in cingulate cortex of young rats. In vitro homocysteine decreased Na+,K+‐ATPase activity and TRAP and increased TBA‐RS in all cerebral structures studied. It is proposed that the alteration of Na+,K+‐ATPase and induction of oxidative stress by homocysteine in cerebral cortex may be one of the mechanisms related to the neuronal dysfunction observed in human homocystinuria.
Interleukin‐4 and interleukin‐13 potentiate interleukin‐1 induced secretion of interleukin‐6 in human osteoblast‐like cells
Authors: Silfverswärd Carl‐Johan , Frost Anders , Brändström Helena , Nilsson Olle , Ljunggren Östen 
Published: July 2004

AbstractFormation of interleukin‐6 (IL‐6) in osteoblasts and bone marrow stromal cells is believed to regulate osteoclast recruitment. The anti‐inflammatory cytokines interleukin‐4 and −13 (IL‐4 and IL‐13) stimulate IL‐6 production in human osteoblasts. We investigated the relative potencies, and synergistic effects, between IL‐4, IL‐13 and interleukin‐1 (IL‐1) on IL‐6 formation in human osteoblast‐like cells.Isolated human osteoblast‐like cells were incubated for 72 h in the presence of various concentrations of IL‐4, IL‐13 and IL‐1, and IL‐6 secretion was measured by ELISA. All cytokines stimulated the secretion of IL‐6. The rank order of potency was IL‐1 ≫ IL‐4 > IL‐13. There were no additive or synergistic effects between IL‐4 and IL‐13. However, co‐stimulation with IL‐1 and IL‐4 resulted in a marked synergistic effect on IL‐6 secretion. Co‐ stimulation with IL‐1 and IL‐13 gave a minor synergistic effect.In conclusion, IL‐4/13 synergistically potentiates IL‐1 induced secretion of IL‐6 in human osteoblast‐like cells. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.