bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression of p270 (ARID1A), a component of human SWI/SNF complexes, in human tumors
Authors: Wang Xiaomei , Nagl Norman G. , Flowers Stephen , Zweitzig Daniel , Dallas Peter B. , Moran Elizabeth
Published: July 2004

Human SWI/SNF complexes use the energy of ATP hydrolysis to remodel chromosomes and alter gene expression patterns. The activity of the complexes generally promotes tissue‐specific gene expression and restricts cell proliferation. The ATPase that drives the complexes, BRG1, is essential for tumor suppression in mice and deficient in a variety of established human tumor cell lines. The complex contains at least 7 other core components, one of which is a large subunit designated p270. p270 RNA is expressed in all normal human tissues examined, but protein expression is severely reduced in at least 2 human tumor lines, C33A and T47D. We show here that loss of p270 in the C33A and T47D cell lines is evident at the RNA level as well as the protein level. The implication that p270 can be informatively screened at the RNA level made a high‐efficiency cancer profiling array approach to screening human tumors feasible. Expression was screened in an array containing RNA‐derived cDNA from 241 tumor and corresponding matched normal tissues from individual patients. p270 deficiency was observed at a higher overall frequency than BRG1 deficiency, but all tissues were not equally affected. Deficiency of p270 was observed most frequently in carcinomas of the breast and kidney. The results were most striking in kidney, where p270 expression was deficient in 30% of carcinoma samples screened. Screening of a panel of established human renal carcinoma–derived cell lines supports the frequency observed in the primary tumor tissue samples. © 2004 Wiley‐Liss, Inc.
Fine mapping of the 11q22–23 tumor suppressive region and involvement of TSLC1 in nasopharyngeal carcinoma
Authors: Lung Hong Lok , Cheng Yue , Kumaran Mande Kuppusamy , Liu Edison Tak‐Bun , Murakami Yoshinori , Chan Cheuk Yu , Yau Wing Lung , Ko Josephine Mun Yee , Stanbridge Eric J. , Lung Maria Li
Published: July 2004

Previous studies transferring an intact chromosome 11 into HONE1 cells demonstrated the functional significance of chromosome regions, 11q13 and 11q22–23, in nasopharyngeal carcinoma (NPC) development. In our study the 11q22–23 region was comprehensively re‐investigated by detailed microsatellite and single nucleotide polymorphism genotyping and by fluorescence in situ hybridization to map precisely the regions containing tumor suppressive activity. We observed 3 chromosomal intervals within 11q22–23 that were commonly lost in the tumor segregants derived from HONE1/chromosome 11 hybrids. One critical region of 0.36 Mb was mapped near the marker D11S2000 and a second 0.44 Mb region was located around the markers D11S1300 and D11S1391. In a third region high allelic loss was also observed at marker D11S4484, where a newly cloned tumor suppressor gene, TSLC1 (tumor suppressor in lung cancer 1), is located. The gene expression analysis showed absence or low expression levels of TSLC1 mRNA in 4 highly tumorigenic NPC cell lines. In addition, the methylation study results show that the TSLC1 promoter region was hypermethylated in all 4 NPC cell lines and re‐expression of the gene occurs in HONE1 cells after 5‐aza‐2′‐deoxycytidine treatment. Hence, the mode of silencing of this candidate TSG in NPC may be attributed to promoter hypermethylation. We have obtained functional evidence for multiple critical tumor suppressive regions in 11q22–23 by fine deletion mapping and for inactivation of TSLC1 being one of these candidate TSGs in NPC development. © 2004 Wiley‐Liss, Inc.
Mechanistic studies on protopanaxadiol, Rh2, and ginseng (Panax quinquefolius) extract induced cytotoxicity in intestinal Caco‐2 cells
Authors: Popovich David G. , Kitts David D.
Published: July 2004

Certain ginsenosides, also known as triterpene glycosides, have been recently reported to have a characteristic effect on cultured intestinal and leukemia cell growth. Ginsenoside aglycones 20(S)‐protopanaxadiol (PD), 20(S)‐protopanaxatriol (PT), and ginsenoside Rh2 have been identified as having a strong effect on reducing cell viability. Furthermore, ginsenoside Rh2 is thought to be a rare ginsenoside not found in all ginseng products. Rather, Rh2 has been recently reported to be a breakdown product of thermal processing of North American ginseng. In this study, pure ginsenosides PD, PT, Rh2 standards and an enriched Rh2 fraction derived from ginseng leaf were tested in cultured Caco‐2 cells for relative cytotoxic potency. PD and Rh2 LC50 were similar after 24 to 72 h, whereas a drop in PT LC50 occurred later at 48 and 72 h. Furthermore, PD and Rh2 affected membrane integrity as indicated by LDH secretion earlier than PT and the enriched Rh2 fraction (P ≤ 0.05). Ginsenoside Rh2 showed the greatest (P ≤ 0.05) build up of necrotic cells (18.3 ± 0.1%) at the respective LC50 after 24 h and PD (21.3 ± 0.3%) showed the largest effect after 44 h of exposure. The effect on apoptotic cells at 44 h of treatment were significantly different (P ≤ 0.05) for Rh2 (21 ± 0.4%), PD (14.6 ± 0.1%), enriched Rh2 leaf fraction (9.9 ± 0.6%), and PT (2.3 ± 0.1%) treatments. Caco‐2 caspase‐3 activity was different between ginsenoside exposure; Rh2 (10.6 ± 0.3 nM pNA) had the greatest (P ≤ 0.05) activity followed by the enriched Rh2 leaf fraction (8.3 ± 0.2 nM pNA), PT (7.3 ± 0.3 nM pNA). The PD (4.8 ± 0.04 nM pNA) treatment was similar to untreated cells (4.3 ± 0.05 nM pNA) in caspase‐3 activity. These results show variable bioactive response in cultured intestinal cell to specific ginsenosides and an enriched Rh2 North American ginseng extract which may be explained on basis of hydrophobic/hydrophilic balance. © 2004 Wiley Periodicals, Inc. J Biochem Mol Toxicol 18:143–149, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20019
The structure and function of auditory chordotonal organs in insects
Authors: Yack Jayne E.
Published: July 2004

Insects are capable of detecting a broad range of acoustic signals transmitted through air, water, or solids. Auditory sensory organs are morphologically diverse with respect to their body location, accessory structures, and number of sensilla, but remarkably uniform in that most are innervated by chordotonal organs. Chordotonal organs are structurally complex Type I mechanoreceptors that are distributed throughout the insect body and function to detect a wide range of mechanical stimuli, from gross motor movements to air‐borne sounds. At present, little is known about how chordotonal organs in general function to convert mechanical stimuli to nerve impulses, and our limited understanding of this process represents one of the major challenges to the study of insect auditory systems today. This report reviews the literature on chordotonal organs innervating insect ears, with the broad intention of uncovering some common structural specializations of peripheral auditory systems, and identifying new avenues for research. A general overview of chordotonal organ ultrastructure is presented, followed by a summary of the current theories on mechanical coupling and transduction in monodynal, mononematic, Type 1 scolopidia, which characteristically innervate insect ears. Auditory organs of different insect taxa are reviewed, focusing primarily on tympanal organs, and with some consideration to Johnston's and subgenual organs. It is widely accepted that insect hearing organs evolved from pre‐existing proprioceptive chordotonal organs. In addition to certain non‐neural adaptations for hearing, such as tracheal expansion and cuticular thinning, the chordotonal organs themselves may have intrinsic specializations for sound reception and transduction, and these are discussed. In the future, an integrated approach, using traditional anatomical and physiological techniques in combination with new methodologies in immunohistochemistry, genetics, and biophysics, will assist in refining hypotheses on how chordotonal organs function, and, ultimately, lead to new insights into the peripheral mechanisms underlying hearing in insects. Microsc. Res. Tech. 63:315–337, 2004. © 2004 Wiley‐Liss, Inc.
Nephridial and gonoduct distribution patterns in Nerillidae (Annelida: Polychaeta) examined by tubulin staining and cLSM
Authors: Worsaae Katrine , Müller Monika C.M.
Published: July 2004

The distribution and configuration of nephridia and gonoducts are described for seven species from seven genera of the interstitial polychaete family Nerillidae. The ciliated nephridia and gonoducts were identified by tubulin staining and examined with a confocal laser scanning microscope. The following species of the seven to nine‐segmented nerillids were examined: Leptonerilla prospera, Nerilla antennata (nine segments); Nerillidium mediterraneum, Trochonerilla mobilis, Gen. sp. A (eight segments); and Aristonerilla brevis, Paranerilla limicola (seven segments). Two of the examined species are hermaphroditic (N. mediterraneum and Gen. sp. A). Segmented nephridia can be found from the first to the last segment, with a total of two to five pairs. One to three pairs of segmented spermioducts are present in all species. One pair of gonoducts is found in all species, except for P. limicola, where they are absent. Nephridia vary in length from half to almost twice the length of a segment and may be curled up in loops. In A. brevis and P. limicola the nephridia are discontinuously ciliated. The distribution and configuration of spermioducts and gonoducts are also variable, although to a lesser extent. The spermioduct distribution is generally consistent within genera and therefore of systematic significance. Nephridia and gonoducts are never found together in the same segments, and the results indicate that gonoducts and nephridia have developed from the same anlagen. The distribution patterns of nephridia and gonoducts are discussed with respect to segmentation, systematics, and development. J. Morphol. 261:259–269, 2004. © 2004 Wiley‐Liss, Inc.
Development of the islets, exocrine pancreas, and related ducts in the Nile tilapia, Oreochromis niloticus (Pisces: Cichlidae)
Authors: Morrison Carol M. , Pohajdak Bill , Tam Janet , Wright James R.
Published: July 2004

Pancreatic development and the relationship of the islets with the pancreatic, hepatic, and bile ducts were studied in the Nile tilapia, Oreochromis niloticus, from hatching to the onset of maturity at 7 months. The number of islets formed during development was counted, using either serial sections or dithizone staining of isolated islets. There was a general increase in islet number with both age and size. Tilapia housed in individual tanks grew more quickly and had more islets than siblings of the same age left in crowded conditions. The pancreas is a compact organ in early development, and at 1 day posthatch (dph) a single principal islet, positive for all hormones tested (insulin, SST‐14, SST‐28, glucagon, and PYY), is partially surrounded by exocrine pancreas. However, the exocrine pancreas becomes more disseminated in older fish, following blood vessels along the mesenteries and entering the liver to form a hepatopancreas. The epithelium of the pancreatic duct system from the intercalated ducts to the main duct entering the duodenum was positive for glucagon and SST‐14 in 8 and 16 dph tilapia. Individual insulin‐immunopositive cells were found in one specimen. At this early stage in development, therefore, the pancreatic duct epithelial cells appear to be pluripotent and may give rise to the small islets found near the pancreatic ducts in 16–37 dph tilapia. Glucagon, SST‐14, and some PPY‐positive enteroendocrine cells were present in the intestine of the 8 dph larva and in the first part of the intestine of the 16 dph juvenile. Glucagon and SST‐14‐positive inclusions were found in the apical cytoplasm of the mid‐gut epithelium of the 16 dph tilapia. These hormones may have been absorbed from the gut lumen, since they are produced in both the pancreatic ducts and the enteroendocrine cells. At least three hepatic ducts join the cystic duct to form the bile duct, which runs alongside the pancreatic duct to the duodenum. J. Morphol. 261:377–389, 2004. © 2004 Wiley‐Liss, Inc.
Fine structure of marsupial hairs, with emphasis on trichohyalin and the structure of the inner root sheath
Authors: Alibardi Lorenzo
Published: July 2004

The fine structure and cornification of marsupial hairs are unknown. The distribution of keratins, trichohyalin, and transglutaminase in marsupial hairs was studied here for the first time by electron microscopy and immunocytochemistry. The localization of acidic and basic keratins in marsupial hairs is similar to that of hairs in placental mammals, and the keratins are mainly localized in the outer root sheath and surrounding epidermis. Marsupial trichohyalin in both medulla and inner root sheath (IRS) cross‐reacts with a trichohyalin antibody that recognizes trichohyalin across placental species, indicating a common epitope(s) among mammalian trichohyalin. Roundish to irregular trichohyalin granules are composed of a network of immunolabeled 10–15‐nm‐thick coarse filaments within an amorphous matrix in which a weak labeling for transglutaminases is present. This suggests that the enzyme, and its substrate trichohyalin, are associated in mature granules. Transglutaminase labeling mainly occurs in condensing chromatin of mature cells of the outer and inner root sheaths, suggesting formation of the nuclear envelope connected with terminal differentiation of these cells. In mature Huxley or Henle layers the filaments lose the immunolabeling for trichohyalin when they are reoriented into parallel rows linked by short bridges, thus suggesting that the filaments with their reactive epitopes are chemically modified during cornification, as seen in the IRS of hairs of placental mammals. The Huxley layer probably acts as a cushion, absorbing the tensions connected with the distalward movement of the growing hair fiber. Variations in stratification of the Huxley layer are probably related to the diameter of the hair shaft. The cytoplasmic and junctional connections between cells of the Huxley layer and the companion layer and the outer root sheath enhance the grip of the IRS and hair fiber within the follicle. The role of cells of the IRS in sculpturing the fiber cuticle and in the mechanism of shedding that allows the exit of hair on the epidermal surface in mammals are discussed. J. Morphol. 261:390–402, 2004. © 2004 Wiley‐Liss, Inc.
Self‐Assembled Monolayer Formed by a Rhenium Complex Containing Hyperbranched Polymer
Authors: Tse Chui W. , Cheng Kai W. , Chan Wai K. , Djurišić Aleksandra B.
Published: July 2004

Summary: The synthesis of a hyperbranched polymer containing a rhenium bipyridine complex is reported. The polymer was synthesized from a monomer that contains two chlorotricarbonyl rhenium(I) bipyridine moieties and a stilbazole ligand, and the polymer was formed by the coordination reaction in one single step. Gel permeation chromatography results showed that the resulting polymer had a strong interaction with the column packing material, which was reduced when the eluent was added with an electrolyte. Both atomic force microscopy and laser light scattering showed that the size of the polymer molecules was in the range between 25–30 nm. A monolayer of polymer molecules could form on a pretreated substrate by the self‐assembly process, which can serve as the building block for multilayer ultrathin film devices.

The metal‐containing hyperbranched polymer synthesized here.

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The metal‐containing hyperbranched polymer synthesized here.
Novel Approach of Evaluating Polymer Nanocomposite Structure by Measurements of the Freezing‐Point Depression
Authors: López‐Manchado Miguel A. , Valentín Juan L. , Herrero Berta , Arroyo Miguel
Published: July 2004

Summary: A novel experimental approach based on the freezing‐point depression of a solvent in a swollen gel has been developed to characterize the structure of nanocomposites. A higher depression in the freezing point has been related with an exfoliated nanocomposite. This increased depression not only depends on the formation of a tighter network but also on the decrease of the size of the solvent cages where the nucleation takes place.

The nucleation process of unfilled and organoclay‐filled natural rubber with the same crosslinking density.

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The nucleation process of unfilled and organoclay‐filled natural rubber with the same crosslinking density.
Ethics and our Journal
Authors: Held Gilbert
Published: July 2004

No abtract
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

It 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

Matrix 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

This 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

The 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

The 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

A 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

Recent 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

The 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

It 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

We 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

The 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

Die 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

This 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.
The bacterial type III secretion system‐associated pilin HrpA has an unusually long mRNA half‐life
Authors: Hienonen Elina , Rantakari Anssi , Romantschuk Martin , Taira Suvi
Published: July 2004

Secondary structures affect mRNA stability and may play a role in protein secretion. We have studied the mRNA of hrpA, which codes for the major structural unit of the type III secretion system‐associated pilus of Pseudomonas syringae pv. tomato, Erwinia carotovora and Pseudomonas syringae pv. phaseolicola. We show that hrpA mRNA has an unusually long half‐live, approximately 33–47 min. We mapped regions in the transcript that affected hrpA mRNA accumulation. Apparently, sequences at both 5′ and 3′ ends affect accumulation. Altering the hypothetical, stable GC rich loop structure in the 3′ end of the transcript decreased transcript levels.
Nucleoside diphosphate kinase of Mycobacterium tuberculosis acts as GTPase‐activating protein for Rho‐GTPases
Authors: Chopra Puneet , Koduri Harshavardhan , Singh Ramandeep , Koul Anil , Ghildiyal Megha , Sharma Kirti , Tyagi Anil K , Singh Yogendra
Published: July 2004

Several bacterial pathogens secrete proteins into the host cells that act as GTPase‐activating proteins (GAPs) for Rho‐GTPases and convert GTP‐bound active form to GDP‐bound inactive form. However, no such effector molecule has been identified in Mycobacterium tuberculosis. In this study, we show that culture supernatant of M. tuberculosis H37Rv harbors a protein that stimulates the conversion of GTP‐bound Rho‐GTPases to the GDP‐bound form. Nucleoside diphosphate kinase (Ndk) was identified as this culture supernatant protein that stimulated in vitro GTP hydrolysis by members of Rho‐GTPases. The histidine‐117 mutant of Ndk, which is impaired for autophosphorylation and nucleotide‐binding activities, shows GAP activity. These results suggest that Ndk of M. tuberculosis functions as a Rho‐GAP to downregulate Rho‐GTPases, and this activity may aid in pathogenesis of the bacteria.
Neuropeptides and the social brain: potential rodent models of autism
Authors: Lim Miranda M. , Bielsky Isadora F. , Young Larry J.
Published: July 2004

Conducting 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

In 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

Formation 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.
Acute effects of N‐acetylcysteine on skeletal muscle microcirculation following closed soft tissue trauma in rats
Authors: Schaser Klaus‐D. , Bail Herman J. , Schewior Lioba , Stover John F. , Melcher Ingo , Haas Norbert P. , Mittlmeier Thomas
Published: July 2004

Trauma‐induced microcirculatory dysfunction, formation of free radicals and decreased endothelial release of nitric oxide (NO) contribute to evolving tissue damage following skeletal muscle injury. Administration of N‐acetylcysteine (NAC) known to scavenge free radicals and generate NO is considered a valuable therapeutic approach. Thus, the objective of this study was to quantitatively analyze the acute effects of NAC on skeletal muscle microcirculation and leukocyte–endothelial cell interaction following severe standardized closed soft tissue injury (CSTI). Severe CSTI was induced in the hindlimbs of 14 male anesthetized Sprague–Dawley rats using the controlled impact injury technique. Rats were randomly assigned (n = 7) to high‐dose intravenous infusion of NAC (400 mg/kg body weight) or isovolemic normal saline (NS). Non‐injured, sham‐operated animals (n = 1) were subjected to the same surgical procedures but did not receive any additional fluid. Creatin kinase (CK) activity was assessed at baseline, 1 h before and 2 h following posttraumatic NAC or NS infusion. Microcirculation of the extensor digitorum longus (EDL) muscle was analyzed using intravital microscopy and Laser‐Doppler flowmetry (LDF). Edema index (EI) was calculated by measuring the EDL wet‐to‐dry weight ratio (EI = injured/contralateral limb). EDL‐muscles were analyzed for desmin immunoreactivity and granulocyte infiltration. Microvascular deteriorations observed following NS‐infusion were effectively reversed by NAC: Functional capillary density was restored to levels found in sham‐operated animals and leukocyte adherence was significantly (p < 0.05) reduced compared to the NS group. NAC significantly (p < 0.05) increased erythrocyte flux determined by Laser‐Doppler flowmetry. Posttraumatic serum CK levels and EI were significantly (p < 0.05) decreased by NAC. During the posttraumatic acute phase, single infusion of NAC markedly reduced posttraumatic microvascular dysfunction, attenuated both leukocyte adherence and tissue infiltration. NAC also decreased CSTI‐induced edema formation and myonecrosis as reflected by attenuated serum CK levels and attenuated loss of desmin immunoreactivity. NAC may serve as an effective therapeutic strategy by supporting microvascular blood supply and tissue viability in the early posttraumatic period. Additional studies aimed at long‐term analysis and investigation of injury severity—or dosage dependency are needed. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Information flow between the stock and option markets: Where do informed traders trade?
Authors: Chen Carl R. , Lung Peter P. , Tay Nicholas S.P.
Published: July 2004

This paper investigates the flow of information between the equity and options markets. We argue that informed traders, in deciding where to place their trades, are not entirely indifferent to option moneyness, degree of information asymmetry, and option liquidity. Unlike some previous studies that find information to flow unilaterally from equity to options markets, we control for the above factors and discover feedback relations between trades in out‐of‐the‐money (OTM) options and the underlying equities. The finding is consistent with the pooling equilibrium hypothesis, which asserts that informed traders trade in both the equity and options markets. Some informed traders are probably attracted to the out‐of‐the money options because of their higher liquidity, lower premiums, and higher delta‐to‐premium ratios, hence, lending support to the liquidity and leverage hypothesis.
BENTHAM AND THE BOOT-STRAPPERS OF JURISPRUDENCE: THE MORAL COMMITMENTS OF A RATIONALIST LEGAL POSITIVIST
Authors: Perreau-Saussine Amanda
Published: July 2004

This article suggests that Jeremy Bentham's principle of utility plays a crucial role in his work as a ground not only of moral or censorial judgment but also of expositorial legal judgment. If we are to reject the characterisation of Bentham as a natural lawyer, the most coherent re-interpretation of his position, a morally sceptical interpretation of his insistence on law as a cause of social order, would be as a noble or enlightened despotism, a decision to defend utility as a politically authoritative but philosophically unjustified principle. It concludes that other rationalist legal positivists face similar versions of this dilemma.
Editorial
Authors: Mark Christopher , Moore Allan
Published: July 2004

To start with the obvious: journals come into being for specific reasons. And if one regards the most influential titles born during the last thirty years or so, it seems that one of the principal motivating factors has been interventionist – an attempt to kick-start a particular subdiscipline, or to promote a hitherto neglected or insufficiently examined field. Thus Music Analysis (Basil Blackwell, 1982) sought to place on a fully professional footing a subdiscipline which, whilst recognized in North America (as Music Theory), was at that time underdeveloped in the UK, while 19th Century Music (University of California Press, 1977) sought ‘to stimulate and focus work on what has for too long been American musicology’s lost century’. There is, however, little need to stimulate the study of twentieth-century music(s): if one includes (as we believe one must) popular music, jazz, film music, and twentieth-century developments in traditional musics, as well as ‘art’ or ‘classical’ music, activity in the field is burgeoning at an impressive rate. What is needed, rather, is a dedicated forum. Earlier journals specializing in twentieth-century music (such as Contact and Perspectives of New Music) tended to act as voices for particular constructions of the field. Established generalist journals have frequently found a place for twentieth-century classical music, and more recently (following the trajectory of musicology in general) have begun to widen their scope to include the discussion of popular, film, and traditional music. But as the first three meetings of the Biennial International Conference on Twentieth-Century Music have
shown (the third, held in Nottingham, UK, in June 2003, is reviewed in these pages), forums
dedicated to the whole range of twentieth-century music promote a synergy and crossfertilization
that will inevitably escape generalist journals or those confined to one corner of
the field. twentieth-century music aims to provide such a forum; and not the least of our hopes
is that, through the contiguity of divergent topics in each issue, the journal will stimulate the
creation of new perspectives by encouraging contact with areas and approaches that we
might not, as individual scholars, otherwise think to engage with.